Omega Owners Forum
Chat Area => General Car Chat => Topic started by: feeutfo on 04 October 2012, 00:46:52
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Tony at Wim pointed out these notices on the sidewall of my tyres the other day, following a discussion on tram lining, and that the set up on my car was fine. Hence he was looking for further reasons as to why the handling had suffered.
These are all conti sc3 on my car. Or have been on my car and replaced.
Rears are currently 265 wide sc3 MO (Mercedes) variant with rim protection. No tram lining afaict.
(http://i344.photobucket.com/albums/p326/chrisgixer/3DC9D986-C731-47C9-94CE-3833B8F80460-1069-000000677D44283C.jpg)
Tyre construction described as...
(http://i344.photobucket.com/albums/p326/chrisgixer/55BABBF0-2558-45A1-A073-D53CD4112009-1069-0000006782E700C4.jpg)
Fronts are currently 235 wide sc3 R01 (Audi) variant with much less rim protection. These are picking up road imperfections and pulling the steering. Tramlining effectively. Compliant ride.
(http://i344.photobucket.com/albums/p326/chrisgixer/0F32B780-902D-4554-920C-7D8A9DDD6F47-1069-00000067704D3718.jpg)
Tyre construction described as...
(http://i344.photobucket.com/albums/p326/chrisgixer/A4C83B54-EFA3-4763-9467-9A853F9A022E-1069-0000006769C6ACA2.jpg)
Just to confirm size.
(http://i344.photobucket.com/albums/p326/chrisgixer/5AE7ACAD-0F3C-45B2-8B58-CC6714354143-1069-00000067768906A4.jpg)
Note, there is a minor fault of slight steering idler play on the car. But this was present on the car with the previous front tyres that where replaced.
These are 245 40 18 MO. 10mm wider than recomended. Absolutely no tramlining at all. But slightly harsh ride when the tyres where cold.
Construction described as
(http://i344.photobucket.com/albums/p326/chrisgixer/14D8795F-95F1-4F4D-84EE-2C0CA596651B-1069-0000006752D1A2E6.jpg)
Obviously construction affects handling. But which construction is best...?
R01 are compliant, smoother ride, but pull.
MO absolutely rock steady in a straight line. But a bit harsh. Suspect they didn't absorb bumps as well, and set the abs off early, ESP over painted yellow lines that count you down approaching roundabouts.
Rears, no problem I can detect through the stock Febi donut bushes.
Anyone got this construction notice on thier tyres...? Or is even remotely interested..? ;D
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First observation, and therefore question:
Are the 235/40s being run at the same pressure as the 245/40s? The extra volume of air in the 245s combined with the extra layer of tread would make for a firmer, less compliant tyre.
Try upping the pressures slightly in the 235s, say 5psi and see what if any difference that makes :y
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Also the premature ABS could be caused by the rolling radius differential between front and rear against what the ABS ecu is expecting to see :-\ Mercs are quite susceptible to this after wheel upgrades.
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Yeeah tried playing with all that. Makes little odds.
Tony's first suggestion on seeing what was on the car was, what pressures?
Settled on 28psi on the front, due to the harder construction sidewall. Increase it and the tram lining is the same but the ride suffers, up to 34.
Ran the Mo at 28 too. Bit low but it worked. Tony replied, yeah can't go any lower. (and higher just makes it progressively harsher with every psi for no gain) I'll fiddle with psi as the ambiant temp drops, but I'm not hopefull tbh.
Tempted to put the old ones back on. :(
Re abs, yes suggested that to TB. But we had pas issues to worry about at that time.
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Do you have the Irmscher paperwork for the wheels?
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Yeeah tried playing with all that. Makes little odds.
Tony's first suggestion on seeing what was on the car was, what pressures?
Settled on 28psi on the front, due to the harder construction sidewall. Increase it and the tram lining is the same but the ride suffers, up to 34.
Ran the Mo at 28 too. Bit low but it worked. Tony replied, yeah can't go any lower. (and higher just makes it progressively harsher with every psi for no gain) I'll fiddle with psi as the ambiant temp drops, but I'm not hopefull tbh.
Tempted to put the old ones back on. :(
Re abs, yes suggested that to TB. But we had pas issues to worry about at that time.
Chris my first thoughts are that 28 psi is too low :-\ although tyre construction will highly effect handling you can arrange it with different presure trials.. I never go below 32 psi.. (but I never used 235 on the front- its too wide and will tramline)
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First thoughts
Do you have the Irmscher paperwork for the wheels?
Do you have the Irmscher paperwork for the wheels?
Sadly not. Abs is same with stock wheels and different tyres again. :-\
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I hope you get to the bottom of this Chris. I never got mine to go straight so I'll be really interested in the cure. Mind you, the Audi goesdead straight :y
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First thoughtsDo you have the Irmscher paperwork for the wheels?
Do you have the Irmscher paperwork for the wheels?
Sadly not. Abs is same with stock wheels and different tyres again. :-\
No probs, I shall copy the relevant bits :y
Also compound makes a huge difference to grip levels, eg Autogrips always give the Abs an TC a good work out, but the Runways I normally use stick like poo to a blanket, and hardly ever cause the Abs to kick in, TC only shows up if giving large pulling in to an opportune gap from a side road ::)
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I hope you get to the bottom of this Chris. I never got mine to go straight so I'll be really interested in the cure. Mind you, the Audi goesdead straight :y
So, for others reading, the Audi has a far more complex and firmer double wishbone type set up, consisting of 4 control arms that effectively form the upper and lower wishbones. It's a far firmer, more accurate set up. Provided the bushes are in good nic of course.
So Audi can afford a softer set up in tyre construction.
Or put another way, if the MO was fitted to the Audi, with it's firmer double wishbone set up, the ride would be most unpleasant.
So, question still stands, what's the best tyre construction for omega...?
Simply saying, for example, fit Dunlops or as here fit continental sc3 doesn't cut it.
I'd be interested to know what the construction of the sport max tt is though, for example...? Or Goodyear f1...?
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I hope you get to the bottom of this Chris. I never got mine to go straight so I'll be really interested in the cure. Mind you, the Audi goesdead straight :y
So, for others reading, the Audi has a far more complex and firmer double wishbone type set up, consisting of 4 control arms that effectively form the upper and lower wishbones. It's a far firmer, more accurate set up. Provided the bushes are in good nic of course.
So Audi can afford a softer set up in tyre construction.
Or put another way, if the MO was fitted to the Audi, with it's firmer double wishbone set up, the ride would be most unpleasant.
So, question still stands, what's the best tyre construction for omega...?
Simply saying, for example, fit Dunlops or as here fit continental sc3 doesn't cut it.
I'd be interested to know what the construction of the sport max tt is though, for example...? Or Goodyear f1...?
will check..
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If I can remember where I parked my 3.2 i'll look at mine. SC3's all round but XL's on the rear IIRC.
Running Toyo T1R's on the DTi so i'll have a look at those as well.
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I found this interesting
http://www.youtube.com/watch?NR=1&v=If5t783NZFY&feature=endscreen (http://www.youtube.com/watch?NR=1&v=If5t783NZFY&feature=endscreen)
http://www.youtube.com/watch?v=IcQ3fB8fZ4E&NR=1&feature=endscreen (http://www.youtube.com/watch?v=IcQ3fB8fZ4E&NR=1&feature=endscreen)
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If I can remember where I parked my 3.2 i'll look at mine. SC3's all round but XL's on the rear IIRC.
Running Toyo T1R's on the DTi so i'll have a look at those as well.
IF.... ? ;D. When did you drive it last...? :-\ ;D
But yes, thank you. :)
I presume similar info is on other brands...? :-\
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Runway Enduros 235/45/17 W97 XL:
Tread: Polyester 2, Steel 2, Nylon 1.
Sidewall: Polyester 2.
:y
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I can check sport maxx tt and sc5 (generic) tomorrow. Too dark now
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I can check sport maxx tt and sc5 (generic) tomorrow. Too dark now
Get the torch out ::) ;D
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I can check sport maxx tt and sc5 (generic) tomorrow. Too dark now
Get the torch out ::) ;D
Time for chips, and its phishing down
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Hankook Ventus V12 Evo: 235/45 ZR17 97Y Max. Load 730 kgs
Plies Tread: 2 Steel + 2 Rayon + 2 Nylon
Sidewall: 2 Rayon
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Toyo Proxes T1R (PXT1R-1) 235 45 17 97Y
Plies - 2 Steel, 1 Rayon, 1 Nylon
Sidewal - 1 Rayon
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Continental SportContact 3
Front
235 45 R17 97W (Extra Load)
Tread Plies 5: 1 Rayon, 2 Steel, 2 Polymide
Sidewall Ply 1: 1 Rayon
Rear
235 45 ZR17 94Y
Tread Plies 5: 1 Polyester, 2 Steel, 2 Nylon
Sidewall Ply 1: 1Polyester
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goodyear eagle f1 asymmetric 2
plies sidewall 1 polyester tread 1 polyester + 2 steel 1 polyamide
(http://i181.photobucket.com/albums/x80/mecdv6/goodyearform.jpg)
Micheline pilot exalto
tread plies 1 polyester 2 steel 1 polyamide sidewall ply 1 polyester
(http://i181.photobucket.com/albums/x80/mecdv6/michelineform.jpg)
Potenza Adrenaline
plies tread 1 polyester 2 steel 1 nylon sidewall 1 polyester
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Hmmm, now where did we get to with this.
Think I've just confused meself tbh. ;D
TB have you got your torch out yet? :)
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Spoke to Dunlop technical today. They recomend the RT range, now that the tt has been superceided. RT being an out and out performance tyre, wet braking giving an A rating, and non of this lightweight fuel saving rubbish involved.
Althought they did say they don't officially do a tyre for the omega. ???
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TB have you got your torch out yet? :)
Yeah, but long since slept since then. Something to do with Raylon and Polyester.
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Same as Cem on the Goodyear F1's with the standard 235/45/17 and it tramlines worse as tyres wear down.
The following is nothing to do with Omega and is just for reference but our M Sport has :
Front 225/35/19 with Plies tread 2 Steel + 2 Rayon + 1 Nylon, sidewall 2 Rayon.
Rear 255/30/19 Plies tread 1 Rayon + 2 Steel + 2 Nylon, sidewall 2 Rayon
and this has zero tramlining on the same stretch of road but has suspension as hard as a bullet.
This all means a big fat zilch to me. :-\
Incidentally, I found my Toyo T1R's 'V' pattern fairly good for lack of tramlining until they got quite low on tread. :y
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TB have you got your torch out yet? :)
Yeah, but long since slept since then. Something to do with Raylon and Polyester.
yep, not sure we'll get anywhere with this though. :-\
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TB have you got your torch out yet? :)
Yeah, but long since slept since then. Something to do with Raylon and Polyester.
yep, not sure we'll get anywhere with this though. :-\
We know the answer. Dunlop Sport Maxx TT. Except they are being withdrawn :(
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Chris, I can say that increasing tire pressure will increase grip , decrease braking distance.. increase cornering ability (lateral-g)..
and decrease tramlining upto an extent (actual amounts may differ tyre to tyre)..
however, tramlining is a function of tyre/road friction-grip .. so a good quality high grip wide tyre will tramline .. you must be suspicious of grip if it doesnt tramline.. as YZ250 says tyres tend to tramline more when they wear and loose the "channels".. why ? because they losse the straight channels that give direction and to an extent surface area increase .. :y
ps: of course ignoring comfort..
pps: I guess actual graph for grip vs pressure would be a U shape upside down so has a limit of course..
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Chris, I can say that increasing tire pressure will increase grip , decrease braking distance.. increase cornering ability (lateral-g)..
and decrease tramlining upto an extent (actual amounts may differ tyre to tyre)..
however, tramlining is a function of tyre/road friction-grip .. so a good quality high grip wide tyre will tramline .. you must be suspicious of grip if it doesnt tramline.. as YZ250 says tyres tend to tramline more when they wear and loose the "channels".. why ? because they losse the straight channels that give direction and to an extent surface area increase .. :y
ps: of course ignoring comfort..
pps: I guess actual graph for grip vs pressure would be a U shape upside down so has a limit of course..
Only that theory falls apart with the Dunlops I have on the Silver Bullet. No tramlining (well, just starting to, but all 4 tyres are now spent), and the grip levels are superb.
The SC5s I have on TBE tramline all over the shop, and the grip is best described as "OK-ish", although other factors are at play on that bloody car.
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Chris, I can say that increasing tire pressure will increase grip , decrease braking distance.. increase cornering ability (lateral-g)..
and decrease tramlining upto an extent (actual amounts may differ tyre to tyre)..
however, tramlining is a function of tyre/road friction-grip .. so a good quality high grip wide tyre will tramline .. you must be suspicious of grip if it doesnt tramline.. as YZ250 says tyres tend to tramline more when they wear and loose the "channels".. why ? because they losse the straight channels that give direction and to an extent surface area increase .. :y
ps: of course ignoring comfort..
pps: I guess actual graph for grip vs pressure would be a U shape upside down so has a limit of course..
Only that theory falls apart with the Dunlops I have on the Silver Bullet. No tramlining (well, just starting to, but all 4 tyres are now spent), and the grip levels are superb.
The SC5s I have on TBE tramline all over the shop, and the grip is best described as "OK-ish", although other factors are at play on that bloody car.
I dont think you claim SC5 is a bad tyre ;D honestly thread pattern effects tramline..
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Each tyre is different, but I find the "best" (for handling) pressures on the SP9000 and Maxx TT's on the bullet is 33psi. Much over 35, it gets very skittish.
Based on 1 driver, no passengers.
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Chris, I can say that increasing tire pressure will increase grip , decrease braking distance.. increase cornering ability (lateral-g)..
and decrease tramlining upto an extent (actual amounts may differ tyre to tyre)..
however, tramlining is a function of tyre/road friction-grip .. so a good quality high grip wide tyre will tramline .. you must be suspicious of grip if it doesnt tramline.. as YZ250 says tyres tend to tramline more when they wear and loose the "channels".. why ? because they losse the straight channels that give direction and to an extent surface area increase .. :y
ps: of course ignoring comfort..
pps: I guess actual graph for grip vs pressure would be a U shape upside down so has a limit of course..
Only that theory falls apart with the Dunlops I have on the Silver Bullet. No tramlining (well, just starting to, but all 4 tyres are now spent), and the grip levels are superb.
The SC5s I have on TBE tramline all over the shop, and the grip is best described as "OK-ish", although other factors are at play on that bloody car.
I dont think you claim SC5 is a bad tyre ;D honestly thread pattern effects tramline..
SC5 is disappointing. I'm basing on grip, rather than stability, due to potential issues with the car.
I think sidewall construction has more effect on tramline. Obviously a lower profile and wider tyre will be more prone.
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Each tyre is different, but I find the "best" (for handling) pressures on the SP9000 and Maxx TT's on the bullet is 33psi. Much over 35, it gets very skittish.
Based on 1 driver, no passengers.
honestly , I wish we could measure the braking distances of dunlop,conti,f1 on the same track with same car and with the same driver..
this could give precious and exact comparison..
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Chris, I can say that increasing tire pressure will increase grip , decrease braking distance.. increase cornering ability (lateral-g)..
and decrease tramlining upto an extent (actual amounts may differ tyre to tyre)..
however, tramlining is a function of tyre/road friction-grip .. so a good quality high grip wide tyre will tramline .. you must be suspicious of grip if it doesnt tramline.. as YZ250 says tyres tend to tramline more when they wear and loose the "channels".. why ? because they losse the straight channels that give direction and to an extent surface area increase .. :y
ps: of course ignoring comfort..
pps: I guess actual graph for grip vs pressure would be a U shape upside down so has a limit of course..
Only that theory falls apart with the Dunlops I have on the Silver Bullet. No tramlining (well, just starting to, but all 4 tyres are now spent), and the grip levels are superb.
The SC5s I have on TBE tramline all over the shop, and the grip is best described as "OK-ish", although other factors are at play on that bloody car.
I dont think you claim SC5 is a bad tyre ;D honestly thread pattern effects tramline..
SC5 is disappointing. I'm basing on grip, rather than stability, due to potential issues with the car.
I think sidewall construction has more effect on tramline. Obviously a lower profile and wider tyre will be more prone.
yep..
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Each tyre is different, but I find the "best" (for handling) pressures on the SP9000 and Maxx TT's on the bullet is 33psi. Much over 35, it gets very skittish.
Based on 1 driver, no passengers.
honestly , I wish we could measure the braking distances of dunlop,conti,f1 on the same track with same car and with the same driver..
this could give precious and exact comparison..
Indeed, which is only why I will (can) give tyre advice based on my personal expereince with a specific tyre on Omegas I've driven :)
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Each tyre is different, but I find the "best" (for handling) pressures on the SP9000 and Maxx TT's on the bullet is 33psi. Much over 35, it gets very skittish.
Based on 1 driver, no passengers.
honestly , I wish we could measure the braking distances of dunlop,conti,f1 on the same track with same car and with the same driver..
this could give precious and exact comparison..
Indeed, which is only why I will (can) give tyre advice based on my personal expereince with a specific tyre on Omegas I've driven :)
I had to say this because you dont accept another condition ;D
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Each tyre is different, but I find the "best" (for handling) pressures on the SP9000 and Maxx TT's on the bullet is 33psi. Much over 35, it gets very skittish.
Based on 1 driver, no passengers.
honestly , I wish we could measure the braking distances of dunlop,conti,f1 on the same track with same car and with the same driver..
this could give precious and exact comparison..
Indeed, which is only why I will (can) give tyre advice based on my personal expereince with a specific tyre on Omegas I've driven :)
I had to say this because you dont accept another condition ;D
I have different expectations to some, so also try to base it on what the expectations are. But, unlike reviews, its still based on how they work on Omegas.
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Each tyre is different, but I find the "best" (for handling) pressures on the SP9000 and Maxx TT's on the bullet is 33psi. Much over 35, it gets very skittish.
Based on 1 driver, no passengers.
honestly , I wish we could measure the braking distances of dunlop,conti,f1 on the same track with same car and with the same driver..
this could give precious and exact comparison..
Indeed, which is only why I will (can) give tyre advice based on my personal expereince with a specific tyre on Omegas I've driven :)
I had to say this because you dont accept another condition ;D
I have different expectations to some, so also try to base it on what the expectations are. But, unlike reviews, its still based on how they work on Omegas.
I wanted to make this test , because I wanted to show that for braking, cornering, results with tests will be proportional..
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The idea behind this, is one single aspect of tyre behaviour, and to try and identify what specifications cause it in a tyre.
That single aspect is Tramlining. Hence the pics and info on construction. I believe the answers on tyre pressure where answered on the first page.
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No-one, not even tyre manufacturers really understand how tyres work - that's why so much of their performance is measured, rather than predicted. It follows that you will really only be successful if you try all variants of construction and pick one that suits your car - which is what vehicle manufacturers do for their new vehicles.
You certainly will not get to the point of "construction type A" = "tramlining severity B".
Have you tried it with standard-sized front wheels ? My hunch is that the width has much to do with the tramlining you're experiencing.
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what size do you actually have fitted at the moment ?
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oh yes - and the construction marking is a US requirement. It's present on pretty much all tyres
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No-one, not even tyre manufacturers really understand how tyres work - that's why so much of their performance is measured, rather than predicted. It follows that you will really only be successful if you try all variants of construction and pick one that suits your car - which is what vehicle manufacturers do for their new vehicles.
You certainly will not get to the point of "construction type A" = "tramlining severity B".
Have you tried it with standard-sized front wheels ? My hunch is that the width has much to do with the tramlining you're experiencing.
more width = more grip (dry,wet)
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No-one, not even tyre manufacturers really understand how tyres work - that's why so much of their performance is measured, rather than predicted. It follows that you will really only be successful if you try all variants of construction and pick one that suits your car - which is what vehicle manufacturers do for their new vehicles.
You certainly will not get to the point of "construction type A" = "tramlining severity B".
Have you tried it with standard-sized front wheels ? My hunch is that the width has much to do with the tramlining you're experiencing.
yep.. although some physics rule still applicable (for some parameters) :y
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]
more width = more grip (dry,wet)
[/quote]
more width usually = more grip in the dry
more width doesn't necessarily mean more grip in the wet
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]
more width = more grip (dry,wet)
more width usually = more grip in the dry
more width doesn't necessarily mean more grip in the wet
if water drain channels correctly designed it will.. :y however, its also dependant on water depth and your speed and weight of course..
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what size do you actually have fitted at the moment ?
I am almost one million % certain it's not to do with width. Eg
245 x 45 x 18 sc3 mo (Mercedes variant) firmer by feel, harsher ride when cold, accepatble compliant ride when warm, run at 28psi to get heat into them and soften the ride, no tram lining at all. Absolutely rock solid. Even with both edges of the fronts worn away.
Currently fitted.
235 x 40 x 18 sc3 a01 (Audi variant) softer side wall, compliant ride, 32 psi is fine, increasing pressure just worsens the ride for no reduction in tram lining, these tram line quite badly (but not as badly as Falkens).
Rears are SC3 265 35 18 95y(?) in MO again. The rear is fine, and was the same tyre fitted while both Audi and Mercedes sc3 variants where on the car.
This isolates the problem to the Audi construction tyre IMO.
The tread pattern is exactly the same, with no exception. The best handling tire for tram lining of the 2 was the wider MO version, with an apparently stiffer side wall, assuming two plyes in the side wall is stiffer. But I don't know if two plyes of one material would naturally be stiffer, than one plye of another. That would depend on the material, something I am not familiar with, obviously.
Hence this thread.
Basically just trying to understand tyre construction and why they choose the construction combinations they do.
But as you say, I don't think we will come up with any usable info this way.
I would be interested to see how the Dunlop tt are made though. The sport maxx and sport maxx tt give an exceptionally planted feel to the car. Tt now replaced by the RT.
But my over riding confusion is, the narrower, softer(?) sidewall variant of sc3 handles worse re tram lining. Me no undystandy. Other than they are clearly designed for different cars.
Moral of the story, if you find a tyre that works for you, stick with the bloody thing, and don't let the tyre shop sell you the next best thing. As it ain't the same.
(main reason for sticking with sc3 is for mileage, which the Dunlop lacks, otherwise it would be Dunlops, no problem at all)
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@ TheBoy, your previous TT have huge levels of grip in they're 10k life.
ANYTHING you fit that's a road summer tyre will have less grip. Sc3 / 5 included.
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what size do you actually have fitted at the moment ?
I am almost one million % certain it's not to do with width. Eg
245 x 45 x 18 sc3 mo (Mercedes variant) firmer by feel, harsher ride when cold, accepatble compliant ride when warm, run at 28psi to get heat into them and soften the ride, no tram lining at all. Absolutely rock solid. Even with both edges of the fronts worn away...................
I used to think that wide low profile tyres would always tramline but how do I explain why 235/45/17 on the Omega tramline badly but 255/30/19 on the bimmer don't. I would love to swap the wheels from the Omega to the bimmer and vise-versa to prove a point but pcd is different so I can't.
Edit:
When I say to prove a point, I mean that I believe the Omega is more susceptible to tramlining due to other geometries. :-\
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I think I've got some sort of answer - are you sure that the two fronts you've had are 245/45 x 18 and 235/40 x 18 ?
As you know, the Omega B suspension is designed around tyres with 11.8 inches hub height. so that means that the roll centre and ground-level offset will be correct as long as you maintain this dimension. Happy handling territory.
Your 245/45s are quite a long way from this - half an inch height-wise to be precise, which is as good as a mile in suspension terms. They are also almost five percent bigger in rolling radius, too - this will certainly increase your braking distances as it'll confuse the ABS.
My considered opinion would be that its very difficult to find a 235 tyre of the appropriate size which won't tramline. And that your inappropriate ( sorry Chris ) size mitigates the tramlining, possibly by extending the ground-level offset and thereby giving more self-correcting torque.
Don't forget that the Omega B front suspension is almost identical to Omega A - so the tyre that they had in mind when they designed it was a 165 x 14.
245/45 x 18 = 780 wrpm & 12.3 inch hub height
235/40 x 18 = 820 wrpm & 11.8 inch hub height
265/35 x 18 = 823 wrpm
Also, the less height (in mm) in the sidewall means a stiffer tyre
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I used to think that wide low profile tyres would always tramline but how do I explain why 235/45/17 on the Omega tramline badly but 255/30/19 on the bimmer don't. I would love to swap the wheels from the Omega to the bimmer and vise-versa to prove a point but pcd is different so I can't.
Edit:
When I say to prove a point, I mean that I believe the Omega is more susceptible to tramlining due to other geometries. :-\
that's easy - the BMW suspension is a far, far more sophisticated design. Key in that is the rack mounted in front of the suspension, which makes it all so much easier.....
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I think I've got some sort of answer - are you sure that the two fronts you've had are 245/45 x 18 and 235/40 x 18 ?
As you know, the Omega B suspension is designed around tyres with 11.8 inches hub height. so that means that the roll centre and ground-level offset will be correct as long as you maintain this dimension. Happy handling territory.
Your 245/45s are quite a long way from this - half an inch height-wise to be precise, which is as good as a mile in suspension terms. They are also almost five percent bigger in rolling radius, too - this will certainly increase your braking distances as it'll confuse the ABS.
My considered opinion would be that its very difficult to find a 235 tyre of the appropriate size which won't tramline. And that your inappropriate ( sorry Chris ) size mitigates the tramlining, possibly by extending the ground-level offset and thereby giving more self-correcting torque.
Don't forget that the Omega B front suspension is almost identical to Omega A - so the tyre that they had in mind when they designed it was a 165 x 14.
245/45 x 18 = 780 wrpm & 12.3 inch hub height
235/40 x 18 = 820 wrpm & 11.8 inch hub height
265/35 x 18 = 823 wrpm
Also, the less height (in mm) in the sidewall means a stiffer tyre
lost me half way through from mitigates. :-[
Just to confirm, the best handling tyre was the mo 245 45 18, then Audi 234 40 18 was next best. The worst ever was a Falken 912 in standard size. (replaced by sc3 generic which where good, but not as good as the biggest size of the mo, which is best.)
So on that evidence, the best handling was furthest from standard, the worst was the Falken on standard rims and sizes. 235 35 17 is it? ???
I'd concede the biggest tyre size might well have failings in lateral grip or some other area related to geometry and roll centres, but the plain fact is IME.. The biggest tyre of the lot tram lined the least.
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Also,I am unable to detect any difference in the abs trigger point between the two sizes.
I think this may be down to a lack of rebound in the b4 shocks. It triggers early it seems.
But we are getting off topic now. :)
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tyres are just like that I'm afraid - that's what I mean about even tyre companies not knowing.
The Omega B facelift design team will have spent a great deal of time auditioning tyres from different manufacturers until they got one that tramlined the least. An OE fitment tyre that you just can't buy. Couldn't ever buy, probably.
So, you're back to auditioning different makes and tread patterns until you find one that suits.
the larger tyre is way too big - I'd be worried about the braking issues primarily.
just out of interest, what offset are the front wheels ?
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how did you get 245/45 x 18 inside the standard strut - I tried that on the race car ( mainly because I had several sets of free tyres ) but couldn't get them to fit.
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Also,I am unable to detect any difference in the abs trigger point between the two sizes.
I think this may be down to a lack of rebound in the b4 shocks. It triggers early it seems.
might be something to do with the 265s on the rear.
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tyres are just like that I'm afraid - that's what I mean about even tyre companies not knowing.
The Omega B facelift design team will have spent a great deal of time auditioning tyres from different manufacturers until they got one that tramlined the least. An OE fitment tyre that you just can't buy. Couldn't ever buy, probably.
So, you're back to auditioning different makes and tread patterns until you find one that suits.
the larger tyre is way too big - I'd be worried about the braking issues primarily.
just out of interest, what offset are the front wheels ?
Et30 they are omega sport stars. Again, I was unable to find any fault with these, or with the previous sport stars that where the vectra offset, Et39 is it?, with the exact same tyres fitted. IMO the offset made absolutely no difference at all, other than the vectra et39(?) sat too close the strut, ,earning tyres with rim protection rubbed slightly.
The handling(tram lining) was not an issue with either offset.
I remain convinced its a tyre construction Issue tbh.
Re reading my posts, I'm coming accross a bit abrupt, Appologies if so, just trying to keep it factual. :)
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how did you get 245/45 x 18 inside the standard strut - I tried that on the race car ( mainly because I had several sets of free tyres ) but couldn't get them to fit.
There's loads of room on et30. Et39(?) is too tight. Can't remember the standard 17" offset.
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Also,I am unable to detect any difference in the abs trigger point between the two sizes.
I think this may be down to a lack of rebound in the b4 shocks. It triggers early it seems.
might be something to do with the 265s on the rear.
no the rears where fitted when I had both mo and Audi variants on the car. Plus driving it, it's defo the front.
Only issue at the back is the slop in the void holes in the rear donuts. Soon to be fixed with poly.
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Just a note, I am concerned purely with tram lining. Just that one single feature, I hate it with a passion.
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Actually, on re checking the pics, the best handling mo has 1 ply rayon, where the slightly worse handling o1 Audi variant has 2ply rayon in the sidewall.
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what size do you actually have fitted at the moment ?
I am almost one million % certain it's not to do with width. Eg.........................................................
Chris, fit 195 65 15 size and see how it doesnt tramline ;D ;D :y
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I think I've got some sort of answer - are you sure that the two fronts you've had are 245/45 x 18 and 235/40 x 18 ?
As you know, the Omega B suspension is designed around tyres with 11.8 inches hub height. so that means that the roll centre and ground-level offset will be correct as long as you maintain this dimension. Happy handling territory.
Your 245/45s are quite a long way from this - half an inch height-wise to be precise, which is as good as a mile in suspension terms. They are also almost five percent bigger in rolling radius, too - this will certainly increase your braking distances as it'll confuse the ABS.
My considered opinion would be that its very difficult to find a 235 tyre of the appropriate size which won't tramline. And that your inappropriate ( sorry Chris ) size mitigates the tramlining, possibly by extending the ground-level offset and thereby giving more self-correcting torque.
Don't forget that the Omega B front suspension is almost identical to Omega A - so the tyre that they had in mind when they designed it was a 165 x 14.
245/45 x 18 = 780 wrpm & 12.3 inch hub height
235/40 x 18 = 820 wrpm & 11.8 inch hub height
265/35 x 18 = 823 wrpm
Also, the less height (in mm) in the sidewall means a stiffer tyre
agreed.. when the tyre size gets bigger both horizontally and vertically, the friction force between tyre and the road is multiplied by those lengths simply (actual forces will be more complex depending of the angles of arms, struts, and other components) and this force reflected to the steering as tramlining..
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Yes, I'm with you - I think its a difference in the tyre construction that causes one to be more susseptible to tramlining than another. That difference won't, however, be in the number of plies of material a versus material b - that's way too simplistic. I've seen this sort of thing from two supposedly identical tyres made on different days.
If you've caused the ABS a headache at the rear, it'll show up in more ABS activity at the front, especially with too big tyres on.
My tyre fouling was radial with the 245s on.
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Yes, I'm with you - I think its a difference in the tyre construction that causes one to be more susseptible to tramlining than another. That difference won't, however, be in the number of plies of material a versus material b - that's way too simplistic. I've seen this sort of thing from two supposedly identical tyres made on different days.
So what differentiates the Audi and Merc variants? :-\
If you've caused the ABS a headache at the rear, it'll show up in more ABS activity at the front, especially with too big tyres on.
TheBoy has the same wheel size, with 235 45 18 tyres fitted. Exact same sizes. On approaching the same roundabout with those yellow warning lines horizontally painted on the road, on the same lines into the roundabout hard on the brakes, mine with sc3 will trip the abs earlier. His absorbs the bumps better, even with four completely different tyres on each corner, runway, auto grip, diamond back and some cheng slime make I can't remember. Since replaced with sc5 all round.
Only thing in the back of my mind is the difference in perception as a driver and passenger. Your more plugged in as a driver and feel the controls better driving mine, but as a passenger in his the mind panic sets in early as not connected so maybe he feels the brakes better. I can't believe I'm harder on brakes than he is though, his braking is ...impressive. Both in bravery and judgement.Edit to add, his is 8j all round though, mine are 8j front,9j rear
My tyre fouling was radial with the 245s on.
Ah, so catching the bottom of the spring cup? There was about 5mill clearance on mine. A member here has a 50 profile tyre on the same wheels. They don't fit, spring cup fouls.
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My tuppence fwiw...
Standard 17" 7Jhave an offset of ET33, with a tyre size of 235/45/17.
My Irmscher Stilas, at 18" 8J have the same ET33 offset with a tyre size of 235/40/18.
My tyre of choice is/are Runway Enduro 916+ Z rated with a 97W load rating.
These are constructed: Sidewall Polyester x2.
Tread Polyester x2, Steel x2, Nylon x1
And are available in 16", 17" and 18".
As long as they are available, I shall continue to buy and use them :y
For a considered and intelligent impression of them, Kevin has just had a pair fitted to his MV6, with favourable first impressions :y
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Yes, I can confirm that there are no tramlining issues with Runway Enduros in 235/45/17 at £67 fitted each. :y
I'm quite impressed with them so far, considering the weather has been truly sh1te since they have been fitted. About the only thing I can't comment on is grip in fine, dry conditions. ;D
TBH, now I've found a setup where my tyres wear evenly I only get annoying tramlining when they are well worn, say under about 3mm of tread, and even then only on poor road surfaces generally. Given that means the last month or two of the tyre's life it's not really a problem. Of course, one man's slight tramlining is another man's uncontrollable. ;)
We have to be sure we're talking about the same thing.
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So what differentiates the Audi and Merc variants? :-\
want a list ? so there's rubber hardness, security of bonding, tread pattern, age of tyre, rubber additives - all of which have much more influence on a tyre's behaviour than the carcass construction.
If you've caused the ABS a headache at the rear, it'll show up in more ABS activity at the front, especially with too big tyres on.
TheBoy has the same wheel size, with 235 45 18 tyres fitted. Exact same sizes. On approaching the same roundabout with those yellow warning lines horizontally painted on the road, on the same lines into the roundabout hard on the brakes, mine with sc3 will trip the abs earlier. His absorbs the bumps better, even with four completely different tyres on each corner, runway, auto grip, diamond back and some cheng slime make I can't remember. Since replaced with sc5 all round.
Only thing in the back of my mind is the difference in perception as a driver and passenger. Your more plugged in as a driver and feel the controls better driving mine, but as a passenger in his the mind panic sets in early as not connected so maybe he feels the brakes better. I can't believe I'm harder on brakes than he is though, his braking is ...impressive. Both in bravery and judgement.Edit to add, his is 8j all round though, mine are 8j front,9j rear
His tyres are way over-size, too, just not as extreme as yours. I am assuming that he has the same tyres all round. Your early ABS onset is caused by the difference in rotational speed between the front and rear wheels on your car.
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2woody as said. WE HAVE THE SAME TYRE SIZES of 235 40 18.
(The 245 45 18 where the previous size that did NOT tramline.)
Both sizes have the abs issue. (if it is an issue)
Sorry. Just to be clear. Unless I'm missing something? :)
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cool - ignore my last post then
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2woody as said. WE HAVE THE SAME TYRE SIZES of 235 40 18.
(The 245 45 18 where the previous size that did NOT tramline.)
Both sizes have the abs issue. (if it is an issue)
Sorry. Just to be clear. Unless I'm missing something? :)
Is that true? Your rears are 265? Unless I've missed a post, if so, sorry.
2woody has a valid point about rolling radii affecting ABS - it has to detect the tiniest variance in rotational speed, under quite complex conditions. If the rolling radii vary, it will push it (artificially) towards the calculated thresholds.
Every Omega (standard) I've driven hard, with the exception of TDs, have a tendency to understeer in fast bends - something I've managed to dial out of the MV6. I see that wider rears will only make that worse. IMHO only, of course.
As for my experience, my MV6 stops far quicker than the Elite. The tyres play a key roll, but obviously the Elite has an additional set of issues at play.
An unfair comparison, given the cars issues, but I can not tell a grip difference between the Sunew/Diamondback/WonTomSoup tyres I had, and the SC5's on now, except less vibration as the wheels are now round. From a tramlining/instability view, the SC5s are awful, to the point Mrs TB wont drive it. After loosing the rear in moderately hard braking (admittedly with a fair amount of lock on), I don't want to either. Though, as said, the car has other long term issues.
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Back on topic please.
Now, this team lining....
TheBoy, as said, the rears do not affect team lining, as they where fitted while both sizes where fitted to the front.
Abs is for another day. But I would add, removing the too big 245 45 18 fronts (that did not tramline) and fitting the matching to the rears diameter 235 45 18 (that do tramline) has made not one jot of difference to the abs.
It's annoying that I have removed the front tyres that are too big, and are supposed to tram line more due to being too big, in favour of a tyre that matches the diameter of the rear, and the straight line handling is worse, and the abs is unchanged.afaict.
You see my point? Obviously something other than size is at play. What is it?
I don't really buy 2woodys list of age, compound, etc. when it's only straight line handling we are talking about. (obviously these affect other areas, fair do's)
The first thing Tony at Wim did, when discussing the problem, and discounting pressures and set up, was to look at the construction badge on the side if the tyre. This is merely a continuation of that thought process. ...?
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And yes, the rears are 9j, but the same diameter.
This was discussed earlier. ::)
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There will be construction differences between different sizes. Beyond what is on the sidewalls.
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I think, quite frankly, we're at a place where "find something that works, and stick with it". Until the tyre manufacturer stops producing, then start again :'(
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But I would add, removing the too big 245 45 18 fronts (that did not tramline) and fitting the matching to the rears diameter 235 45 18 (that do tramline)
Sorry to quote out of context, but what were load and speed ratings?
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I can check the mo, but the current tyres are listed in the pics.
Can I direct the honourable member to post 1 page 1?
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I can check the mo, but the current tyres are listed in the pics.
Can I direct the honourable member to post 1 page 1?
Not mentioned AFAICS.
I ask, as some sizes of MO, when I was looking, were not available with load rating of 93 (or higher), as specified by GM. Certainly the size I was after was only available in MO with a rating of 91.
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I can check the mo, but the current tyres are listed in the pics.
Can I direct the honourable member to post 1 page 1?
Not mentioned AFAICS.
I ask, as some sizes of MO, when I was looking, were not available with load rating of 93 (or higher), as specified by GM. Certainly the size I was after was only available in MO with a rating of 91.
mo 93y, what size did you look under...?
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I can check the mo, but the current tyres are listed in the pics.
Can I direct the honourable member to post 1 page 1?
Not mentioned AFAICS.
I ask, as some sizes of MO, when I was looking, were not available with load rating of 93 (or higher), as specified by GM. Certainly the size I was after was only available in MO with a rating of 91.
mo 93y, what size did you look under...?
235/40/18
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I can check the mo, but the current tyres are listed in the pics.
Can I direct the honourable member to post 1 page 1?
Not mentioned AFAICS.
I ask, as some sizes of MO, when I was looking, were not available with load rating of 93 (or higher), as specified by GM. Certainly the size I was after was only available in MO with a rating of 91.
mo 93y, what size did you look under...?
235/40/18
thats not the size mo i had, probably why.
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so what are we looking at for load rating TB?
iirc those Falkens where 95y which where awfull for tramlining, yet they where a higher load rating and narrower( in standard size) than mo by some way
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Every Omega (standard) I've driven hard, with the exception of TDs, have a tendency to understeer in fast bends - something I've managed to dial out of the MV6. I see that wider rears will only make that worse. IMHO only, of course.
Not necessarily. Even in tyres of the same make, the amount of stretch in the tyre to meet the wheel greatly affects the grip available. Tyres with a lot of stretch ( think "Euro style" ) have very little flex available. This is going to affect the understeer gradient.
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Back on topic please.
I don't really buy 2woodys list of age, compound, etc. when it's only straight line handling we are talking about. (obviously these affect other areas, fair do's)
I'm sorry Chris - it may be my fault for not putting it right. The "other things" above are really much more influential on all aspects of the tyres performance in all conditions - even for tramlining.
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want a list ? so there's rubber hardness, security of bonding, tread pattern, age of tyre, rubber additives - all of which have much more influence on a tyre's behaviour than the carcass construction.
Sorry been lazy and copied the above from your post 2woody.
So we have;
Rubber hardness. I would have thought the same between mo and o1 but could well be different. Cirtainly it doesn't seem to lack grip between one or the other.
Security of bonding. Ok, don't much about that.
Tread pattern. Exactly the same between mo and o1. Both are sc3
Age of tyres. The worse tramlining o1 is at least two years younger by purchase date. The date stamps on both are a couple of months prior to that, and are the same per axle set. So the dates don't imply any oddity there. Both where purchased from the same wear house that has no windows, so no sunlight killing the compound. They have a massive turnaround of tyres anyway. They would not be on the shelf long.
Rubber additives. Trade secret I'm guessing?
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In addition,
Load rating
Extra load on the 01 which tramlines
93y on the mo which doesn't.
Construction label
Sidewall 2ply rayon on the o1 extra load ...tramlines
Sidewall 1ply rayon on the mo 93y ....doesn't.
I thought the sidewall material was different, on checking the pictures it's not. I guess that's what happens when reading the label upside down. ;D
Speed rating
Same.
What rating is extra load? Compared to 93y.
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Oh, and I never answered Kevs post earlier.
On a scale of 1-10,
10 being worsened with Falkens.
( You remember driving with two of those fitted. And i'm sure TB remembers driving with all 4 fitted )
.
.8 TB's totals cabbaged clown car michelins,here
.
.
.
4 the current sc3 o1 Audi variant is about here
3 or maybe here
.
1 best for not tramling being mo sc3
So not a massive issue. But it's bloody annoying having coffee up for them.
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Oh, and I never answered Kevs post earlier.
On a scale of 1-10,
10 being worsened with Falkens.
( You remember driving with two of those fitted. And i'm sure TB remembers driving with all 4 fitted )
.
.8 TB's totals cabbaged clown car michelins,here
.
.
.
4 the current sc3 o1 Audi variant is about here
3 or maybe here
.
1 best for not tramling being mo sc3
So not a massive issue. But it's bloody annoying having coffee up for them.
The SC5s are coming in around a 9....
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Rubber hardness. I would have thought the same between mo and o1 but could well be different. Cirtainly it doesn't seem to lack grip between one or the other.
I would hazard, with all other things equal (size/speed etc), the compound would be the primary difference between the different manufacturer options.
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Oh, and I never answered Kevs post earlier.
On a scale of 1-10,
10 being worsened with Falkens.
( You remember driving with two of those fitted. And i'm sure TB remembers driving with all 4 fitted )
.
.8 TB's totals cabbaged clown car michelins,here
.
.
.
4 the current sc3 o1 Audi variant is about here
3 or maybe here
.
1 best for not tramling being mo sc3
So not a massive issue. But it's bloody annoying having coffee up for them.
The SC5s are coming in around a 9....
bloody hell, worse than the clown tyres? Do you think the other issues are included in that 9 or is that purely tyres?
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Who knows.
The car went from Heinz 57 (no real issues, bar lack of grip), to those I borrowed from you (no real issues, except rears keen to light up), had a load of suspension work done, stayed on yours for about 2 weeks, then onto SC5s.
All the fun started with the SC5s. I assumed it was the release agent, as they initially squealed at corners or brakes.
So far, I have nothing good to say about them. But as you know, other factors are at play here.
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SC5 235/40/18
(http://i14.photobucket.com/albums/a319/IamTheBoy/9083E6B4-6FBD-4F44-AB0C-9AF63CD58587-4631-0000032438824D6A.jpg)
Maxx TT 235/45/17
(http://i14.photobucket.com/albums/a319/IamTheBoy/3263B6A9-0CC6-4CCD-8AF9-52514D68E755-4631-000003242F8EDD40.jpg)
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Yep, I'm liking the 1 rayon sidewall, same as mo. ...for what it's worth...?
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Yep, I'm liking the 1 rayon sidewall, same as mo. ...for what it's worth...?
I don't think you can use it for any judgement.
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Yep, I'm liking the 1 rayon sidewall, same as mo. ...for what it's worth...?
I don't think you can use it for any judgement.
ok, mines a fraction of the problem yours is. Not MY f@ckin car. ;D
Case closed then? Yes?
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Yep, I'm liking the 1 rayon sidewall, same as mo. ...for what it's worth...?
I don't think you can use it for any judgement.
ok, mines a fraction of the problem yours is. Not MY f@ckin car. ;D
Case closed then? Yes?
Yep. Runway Enduros and you can afford to bin them at 4mm. :y
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A ringing endorsement from Kevin then 8)
They grip well down to 2mm, but get quite feathery the closer you get to the limit :-X
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There you go then J. Runway Enduros. Fixed. :)
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you know my approach to tyre makes........
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you know my approach to tyre makes........
Btw I double checked, it wasn't 245 45 profile at all. It was 245 40, hence it fitted.
According to irmschers tuv cirtificate for sport stars, 245 40 18 93w is the correct listed size, this is the same as the NON tramlining mo, and one of two options.
The other being 235 40 zr18 which is the same as the Audi ones I have fitted now. The only difference is the these are extra load. But I don't know what load that equates to. Does extra load mean it would have a load figure of more than 93?
...and what is/how do you work out, the load rating of a tyre for a car? I'm thinking anything over 93 is too much for omega, potentially. Cirtainly the tuv cirts don't recomend anything higher with these wheels.
http://www.irmscher.de/abe/de/7_61_10_490_491.pdf
It's a fairly detailed document.
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TIS says 94W for a 2003 3.2 on 235/45/17 on a 3.2 (actually, the same for all V6).
My understanding of these ratings (load and speed) is that they can be exceeded, but never reduced. Doing so may not only impact the validity of the insurance, but could end up leading to catasphoric failure, which will end in tears at bedtime.
Load rating values (ie, max weight applied to that tyre) is described:
http://www.tesco-tyres.com/help/load-rating
Now GM do not list any 18" sizes, but I don't see how the load index would reduce with a larger size, as each wheel still needs to carry the same weight.
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...and what is/how do you work out, the load rating of a tyre for a car? I'm thinking anything over 93 is too much for omega, potentially. Cirtainly the tuv cirts don't recomend anything higher with these wheels.
load ratings of tyres are, you'll not be surprised to find out, measured from a completed tyre during a test.
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I was going to let this go, but having driven the car since, much as i love it, the front tyres are really ruining it for me tbh. Its not massive tram lining, but...
So load rating then... :)
Here's the chassis label on my b pillar.
(http://i344.photobucket.com/albums/p326/chrisgixer/CCECDC98-5DFC-446A-84E9-14471FAB8466-6048-000005185A48C669.jpg)
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According to page 213 of the owners manual the first line under the chassis number means;
Permisable gross vehicle weight of 2200kg
" gross vehicle train weight 4075kg for pikeys only
" max front axle load. 1080kg
" max rear axle load. 1155kg
The car ia a saloon, guess estates will be different. ::)
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So According to this load rating chart
http://www.tesco-tyres.com/help/load-rating
A load rating of 87 would cover the front axle at 545 a tyre. 1090kg total
A load rating of 89 would cover the rear axle at 580 a tyre. 1160kg total
That gives a total load rating covered weight of. ..........2250kg gross
Ok not much room for error there, but why do we need a load rating of 94 on the front axle? Giving 1340kg load rating at 670kg a tyre. That's 260kg more load rating than required JUST on the front axle.(working worst way admittedly)
What am I missing? :-\
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Wikipedia gives omega curb side weight of 1530kg, although I'm not sure how accurate that is as it covers all the facelift options.
If accurate that gives the omega a load carrying capacity of 670kg, up to 2200kg
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What am I missing? :-\
...and don't say custard. ;D
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Parkers give 1700kg for the 3.2 saloon.
http://www.parkers.co.uk/cars/reviews/facts-and-figures/vauxhall/omega/saloon-1994/20769/
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I would suggest that the extra 20-25% load ability is there to allow for lateral forces acting on each wheel as the car is driven, plus a safe margin. I doubt it would be possible to reach 1.5g in an Omega without dying un the process :-\
A simple way of proving this would be to buy some tyres with the lower ratings and drive it as normal. I doubt that they would last long and the car would become a wallowing jelly :-\
For what they cost, get a pair of Runways, and try them for a comparison. If you don't get on with them then I'll have them off you :y
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I could understand it on the rear, but on the front?
Seems to me irmschers load rating of 91 on the front and 93 on the rear is nearer the mark.
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Braking hard into a corner and you've got the 500+ kgs of one front corner of the car plus the weight transfer from the other three quarters all being loaded onto the outer front wheel. The momentary loading on that one corner could easily exceed a ton :-\
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Ok so going back to 2woody's post about a tyre completing a tyre test, is it fair to say that Irmscher have tested those load ratings, given the tuv certificate?
And would less sidewall(ie a lower profile) be a stronger sidewall for instance. And therefor a lower profile would cope better and allow a lower load rating?
Especially given the only difference between the tram lining o1 sc3 and the approved sizes in the tuv cirt is that my o1 sc3 have extra load stamped on them.
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Perhaps :-\ but as 2woody mentioned earlier the number of plies in the sidewall are irrelevant... Would a single ply sidewall of 6mm be weaker than a two ply one made up of two three mm plies :-\ okay a simplified idea, but...
There is obviously a significant difference in the construction of the tyres which is causing the problem, something only the tyre manufacturer can answer.
Lower profile tyres will always flex less as there is simply less vertical give in the sidewalls.
Whether they actually allow a lower load rating depends entirely on the construction of the tyres including the number of plies and also how they are actually made :-\
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I could understand it on the rear, but on the front?
Seems to me irmschers load rating of 91 on the front and 93 on the rear is nearer the mark.
Who would you tend to believe, GM who spent milliions developoing the car, or some tinpot styling company who can't even make the bodykits fit properly ::)
Of course, GM may have picked higher rated tyres for other reasons, based upon their findings when they were testing.
The little Rover, for eg, had a top speed of 110, maybe 115mph. Yet came with V rated tyres. Mine always had V rated tyres, as thats what Rover specced. Its handled like a dream - one of the best FWD cars I've driven for handling. A college had a 1.4 one that had 14" rims, and had H rated tyres, that just understeered everywhere under power. So there is something different in the construction for speed ratings (both were P6000s). I wonder if its similar for load ratings? Probably not relevent, just thinking aloud really.
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If gm had tested an 18" tyre, maybe.
The only evidence we have of a tested 18" tyre has not been taken into account by either of us.
By coincidence, the one I bought is the correct type, and behaves well.
The one you bought is not to spec and misbehaves.
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If gm had tested an 18" tyre, maybe.
The only evidence we have of a tested 18" tyre has not been taken into account by either of us.
By coincidence, the one I bought is the correct type, and behaves well.
The one you bought is not to spec and misbehaves.
I had wondered if rim size would make a difference. But GM specifiy that for all the (standard - 15,16,17) sizes.
Irrespective of the rim size, if it is purely on weight and calculated forces, that will not vary with rim size.
I think you just happened to stumble upon a tyre that worked well on the car. Same as I did with the Rover... ...I strayed to other brands, supposedly superior, only to end in a poorer tyre.
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If gm had tested an 18" tyre, maybe.
The only evidence we have of a tested 18" tyre has not been taken into account by either of us.
By coincidence, the one I bought is the correct type, and behaves well.
The one you bought is not to spec and misbehaves.
I had wondered if rim size would make a difference. But GM specifiy that for all the (standard - 15,16,17) sizes.
Irrespective of the rim size, if it is purely on weight and calculated forces, that will not vary with rim size.
I think you just happened to stumble upon a tyre that worked well on the car. Same as I did with the Rover... ...I strayed to other brands, supposedly superior, only to end in a poorer tyre.
I'm sure somebody said that earlier, let me check... Oh yes, it was me. ;D happened to be the correct one too. ::)
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If gm had tested an 18" tyre, maybe.
The only evidence we have of a tested 18" tyre has not been taken into account by either of us.
By coincidence, the one I bought is the correct type, and behaves well.
The one you bought is not to spec and misbehaves.
I had wondered if rim size would make a difference. But GM specifiy that for all the (standard - 15,16,17) sizes.
Irrespective of the rim size, if it is purely on weight and calculated forces, that will not vary with rim size.
I think you just happened to stumble upon a tyre that worked well on the car. Same as I did with the Rover... ...I strayed to other brands, supposedly superior, only to end in a poorer tyre.
I'm sure somebody said that earlier, let me check... Oh yes, it was me. ;D happened to be the correct one too. ::)
I do fail to see how Irmscher feel they can specify a tyre that doesn't meet GM's spec. But then, our experience of Irmscher's engineering..... ;)
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If gm had tested an 18" tyre, maybe.
The only evidence we have of a tested 18" tyre has not been taken into account by either of us.
By coincidence, the one I bought is the correct type, and behaves well.
The one you bought is not to spec and misbehaves.
I had wondered if rim size would make a difference. But GM specifiy that for all the (standard - 15,16,17) sizes.
Irrespective of the rim size, if it is purely on weight and calculated forces, that will not vary with rim size.
I think you just happened to stumble upon a tyre that worked well on the car. Same as I did with the Rover... ...I strayed to other brands, supposedly superior, only to end in a poorer tyre.
I'm sure somebody said that earlier, let me check... Oh yes, it was me. ;D happened to be the correct one too. ::)
I do fail to see how Irmscher feel they can specify a tyre that doesn't meet GM's spec. But then, our experience of Irmscher's engineering..... ;)
do gm produce an 18?
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....and let's face it, GM's engineering is hardly faultless either.
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....and let's face it, GM's engineering is hardly faultless either.
Oh, indeed, yes, couldn't agree more.
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If gm had tested an 18" tyre, maybe.
The only evidence we have of a tested 18" tyre has not been taken into account by either of us.
By coincidence, the one I bought is the correct type, and behaves well.
The one you bought is not to spec and misbehaves.
I had wondered if rim size would make a difference. But GM specifiy that for all the (standard - 15,16,17) sizes.
Irrespective of the rim size, if it is purely on weight and calculated forces, that will not vary with rim size.
I think you just happened to stumble upon a tyre that worked well on the car. Same as I did with the Rover... ...I strayed to other brands, supposedly superior, only to end in a poorer tyre.
I'm sure somebody said that earlier, let me check... Oh yes, it was me. ;D happened to be the correct one too. ::)
I do fail to see how Irmscher feel they can specify a tyre that doesn't meet GM's spec. But then, our experience of Irmscher's engineering..... ;)
do gm produce an 18?
all on gay wheel drives in uk no doubt...?
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Nothing in the Insignia Specs, come with 18" and 19" as standard on Elite and VXR, with 20" optional :-\
Is it summat that TIS might shed some light on :-\
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I wonder... ::) TIS does seem to have a lot of answers, he did mention TIS didn't he. ::)
Does TIS specify anything? I do wonder you know... About TIS.
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Perhaps the resident Insignia Owner can shed some light :-\ Ought to be summat useful in the Owners Manual given that the grotbox is a similar size and weight to the Omega ...
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Perhaps the resident Insignia Owner can shed some light :-\ Ought to be summat useful in the Owners Manual given that the grotbox is a similar size and weight to the Omega ...
Did someone mention custard ? ::)
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Ah ha, there you are :y
Does your owners manual say owt about suitable tyres and their respective load ratings for the various wheel sizes, specifically 18", 19" and 20"... :y
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Ah ha, there you are :y
Does your owners manual say owt about suitable tyres and their respective load ratings for the various wheel sizes, specifically 18", 19" and 20"... :y
It's in the car, will dig it out in a bit :y
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Ah ha, there you are :y
Does your owners manual say owt about suitable tyres and their respective load ratings for the various wheel sizes, specifically 18", 19" and 20"... :y
No.
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Surprised face on.
Bugger.
Surprised face off.
Thanks for looking :y
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Surprised face on.
Bugger.
Surprised face off.
Thanks for looking :y
It was a pleasure :y
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Ah ha, there you are :y
Does your owners manual say owt about suitable tyres and their respective load ratings for the various wheel sizes, specifically 18", 19" and 20"... :y
I fail to see why the load rating should vary with rim size :-\
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I agree, the Runways I buy are all 97W XL regardless of size. Lateral forces are the dictating factor, and they don't reduce by changing the wheels...
Tunnie might get away with lower rated tyres, but I suspect the rest of us would probably be have a blowout a week if we're lucky :-\
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Are wheels in motion still a member here?
I was going to pm Tony a link, but couldnt find them in the member search.
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Tried to do a spot of window shopping on the blackboots site earlier, but computer said no :-\ wouldn't even attempt to load the shop page :-\
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Are wheels in motion still a member here?
I was going to pm Tony a link, but couldnt find them in the member search.
http://www.omegaowners.com/forum/index.php?action=profile;u=154
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Tried to do a spot of window shopping on the blackboots site earlier, but computer said no :-\ wouldn't even attempt to load the shop page :-\
I still get in fine .. to the main site
http://www.wheels-inmotion.co.uk
but the link to tyres fails ... :(
:)
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Are wheels in motion still a member here?
I was going to pm Tony a link, but couldnt find them in the member search.
http://www.omegaowners.com/forum/index.php?action=profile;u=154
Ta. :)
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What am I missing? :-\
...and don't say custard. ;D
sorry again, Chris....
How it works is this.....
The car manufacturer designs a car and chooses a hub height and a wheel revs per mile. It then goes shopping to tyre manufacturers and tries either prototypes or simulators on the manufacturer's first guess at the tyre. Of course the weight is important too, but the plain fact, at least for passenger cars is that the tyre manufacturer would never develop a tyre with a load index less than likely for any vehicle.
It certainly isn't the case that the manufacturer requires a tyre to match the load index that it has designed.
of course, the manufacturer and tyre supplier keep working together and the detail geometry, construction - and by that, I mean things like tread block radii, etc., and compounds, so that any potential problems have been ireoned out prior to launch.
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Why you running 235 40 18 Chris?
245 40 18 here, find 245 to big?
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Why you running 235 40 18 Chris?
245 40 18 here, find 245 to big?
yes very slightly too wide, slight rubbing on the outside edge on the wheel arch liner under full compression with irmscher springs giving 30mm drop. Only slight.
10mm less width and all is well.
Irmscher recommend -1.40 camber with their suspension which might give clearance.
But -1.40 is too aggressive on tyre wear, and too twitchy in a straight line. Mine is set to -1.10 as normal.
So went for 235.
You prefer 245 width?
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What am I missing? :-\
...and don't say custard. ;D
sorry again, Chris....
How it works is this.....
The car manufacturer designs a car and chooses a hub height and a wheel revs per mile. It then goes shopping to tyre manufacturers and tries either prototypes or simulators on the manufacturer's first guess at the tyre. Of course the weight is important too, but the plain fact, at least for passenger cars is that the tyre manufacturer would never develop a tyre with a load index less than likely for any vehicle.
It certainly isn't the case that the manufacturer requires a tyre to match the load index that it has designed.
of course, the manufacturer and tyre supplier keep working together and the detail geometry, construction - and by that, I mean things like tread block radii, etc., and compounds, so that any potential problems have been ireoned out prior to launch.
ok so Mr tyre maker turns up, and his tyres tramline like a bitch, what does he do to fix it, exactly?
And let's say you've got 18's fitted, what tyres would you buy? Exactly? :)
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Why you running 235 40 18 Chris?
245 40 18 here, find 245 to big?
yes very slightly too wide, slight rubbing on the outside edge on the wheel arch liner under full compression with irmscher springs giving 30mm drop. Only slight.
10mm less width and all is well.
Irmscher recommend -1.40 camber with their suspension which might give clearance.
But -1.40 is too aggressive on tyre wear, and too twitchy in a straight line. Mine is set to -1.10 as normal.
So went for 235.
You prefer 245 width?
This time i'm not on lowering spring and can't remember if on my mv6 at the time with 245 but fair call, got 235's for from on plod as i think fronts rub on turn... :(
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Mr tyre manufacturer will go away and try altering compound and tread pattern until it works. Usually. I have known them give up, tho.
On 18's - I usually buy a set before each track-day and then finish them off on the road. Cheapest, always. On the couple that I've had that tramlined, I've always found it to be the car and not the tyres.
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Mr tyre manufacturer will go away and try altering compound and tread pattern until it works. Usually. I have known them give up, tho.
On 18's - I usually buy a set before each track-day and then finish them off on the road. Cheapest, always. On the couple that I've had that tramlined, I've always found it to be the car and not the tyres.
since these ao1 where fitted, I think the rear wb bushes have failed, and the steering idler was replaced.
I could pick out the differences with the steering idler before and after. Slight steering play and a creak.
But I can't feel any difference with the rear wb bushes. ...another creak has developed so i need to check them again. But they where fine when ao1 where fitted because I checked while the car was jacked at the tyre fitters.
So, as I've made that about as clear as mud;
No tram lining.
Mo came off with worn in/outside edges and plenty of tread in the middle.
Rear bushes checked, and fine, while jacked at tyre fitters.
Ao1 went on, drove it away from the tyre fitters, instant tram lining.
Creak and slight play in idler, replaced, slightly better steering, tramlining no change.
Different creak developed, might be rear wb bushes, tramlining is same.
Conclude, mo don't tram line, ao1 do. Why?
Not tread pattern, it's exactly the same.
Don't think it's compound, grip and wear is very similar Afaict.
It's the narrower ao1 (235wide) the plays up so its not to do with width.
Mo where on both sets of sport stars in et30 and 38. No tramlining, it's not the et.
It's not the car as the before and after tyre change was night and day.
Ao1 pressures tried between 28 psi to 35. No affect on tramlining, just harsher ride.
IMO, it's the construction of the tyre, unless anyone else can think of another aspect that we could eliminate. ...?
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Also, TheBoy has a sweet handling mv6 with worn Dunlop sport max TT.
He also has an elite with other issues, but new sc5. To me, the sc5 are poor in respect to tram lining.
The wheels have been swapped between the two cars. I wonder how the mv6 drives now...?
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How many sets of ao1 have you had? It's not impossible to get a bad tyre..
What about the runout indicators - can you remember where they were and if you had a matched pair of tyres put on the front?
Just wondering if you could be chasing ghosts, so to speak..
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Just two ao1 on the front.
Can't remember the lines being present, but I'll cirtainly look. :y
I know the mo red and green lines hung in there really well. Still present once removed.
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I think you're still looking at it too simplistically. I suspect there is more than just "number of plys" or "sidewall material" etc etc between manufacturer specific versions of a specific tyre. In fact, you already know that in visual differences between the MO and AO1 variants.
Its more than likely that the compound will vary. The tread pattern will likely remain the same for a specific "model" of tyre, such as SC3.
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Additionally, I guess MO is german for some variant of Merc OE, and AO is german for some variant of Audi OE. If so, if follows that there is possibly more than 1 type of Audi fitment, if they felt the need to call on AO1 ?
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Also, TheBoy has a sweet handling mv6 with worn Dunlop sport max TT.
He also has an elite with other issues, but new sc5. To me, the sc5 are poor in respect to tram lining.
The wheels have been swapped between the two cars. I wonder how the mv6 drives now...?
?
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Also, TheBoy has a sweet handling mv6 with worn Dunlop sport max TT.
He also has an elite with other issues, but new sc5. To me, the sc5 are poor in respect to tram lining.
The wheels have been swapped between the two cars. I wonder how the mv6 drives now...?
?
I am purposely not answering at this early stage...
...esp as you have probably done more miles in it than I have ;)
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Mr tyre manufacturer will go away and try altering compound and tread pattern until it works. Usually. I have known them give up, tho.
On 18's - I usually buy a set before each track-day and then finish them off on the road. Cheapest, always. On the couple that I've had that tramlined, I've always found it to be the car and not the tyres.
since these ao1 where fitted, I think the rear wb bushes have failed, and the steering idler was replaced.
I could pick out the differences with the steering idler before and after. Slight steering play and a creak.
But I can't feel any difference with the rear wb bushes. ...another creak has developed so i need to check them again. But they where fine when ao1 where fitted because I checked while the car was jacked at the tyre fitters.
So, as I've made that about as clear as mud;
No tram lining.
Mo came off with worn in/outside edges and plenty of tread in the middle.
Rear bushes checked, and fine, while jacked at tyre fitters.
Ao1 went on, drove it away from the tyre fitters, instant tram lining.
Creak and slight play in idler, replaced, slightly better steering, tramlining no change.
Different creak developed, might be rear wb bushes, tramlining is same.
Conclude, mo don't tram line, ao1 do. Why?
Not tread pattern, it's exactly the same.
Don't think it's compound, grip and wear is very similar Afaict.
It's the narrower ao1 (235wide) the plays up so its not to do with width.
Mo where on both sets of sport stars in et30 and 38. No tramlining, it's not the et.
It's not the car as the before and after tyre change was night and day.
Ao1 pressures tried between 28 psi to 35. No affect on tramlining, just harsher ride.
IMO, it's the construction of the tyre, unless anyone else can think of another aspect that we could eliminate. ...?
don't forget the biggest difference of the lot - the second set had 8mm of tread, whereas the first set didn't
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Mr tyre manufacturer will go away and try altering compound and tread pattern until it works. Usually. I have known them give up, tho.
On 18's - I usually buy a set before each track-day and then finish them off on the road. Cheapest, always. On the couple that I've had that tramlined, I've always found it to be the car and not the tyres.
since these ao1 where fitted, I think the rear wb bushes have failed, and the steering idler was replaced.
I could pick out the differences with the steering idler before and after. Slight steering play and a creak.
But I can't feel any difference with the rear wb bushes. ...another creak has developed so i need to check them again. But they where fine when ao1 where fitted because I checked while the car was jacked at the tyre fitters.
So, as I've made that about as clear as mud;
No tram lining.
Mo came off with worn in/outside edges and plenty of tread in the middle.
Rear bushes checked, and fine, while jacked at tyre fitters.
Ao1 went on, drove it away from the tyre fitters, instant tram lining.
Creak and slight play in idler, replaced, slightly better steering, tramlining no change.
Different creak developed, might be rear wb bushes, tramlining is same.
Conclude, mo don't tram line, ao1 do. Why?
Not tread pattern, it's exactly the same.
Don't think it's compound, grip and wear is very similar Afaict.
It's the narrower ao1 (235wide) the plays up so its not to do with width.
Mo where on both sets of sport stars in et30 and 38. No tramlining, it's not the et.
It's not the car as the before and after tyre change was night and day.
Ao1 pressures tried between 28 psi to 35. No affect on tramlining, just harsher ride.
IMO, it's the construction of the tyre, unless anyone else can think of another aspect that we could eliminate. ...?
don't forget the biggest difference of the lot - the second set had 8mm of tread, whereas the first set didn't
so, they tram line because they are new? :-\
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no, but they might because they're taller.
they might because they're flexing more than the previous tyres because they have more rubber to flex and because the compound is softer
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no, but they might because they're taller.
they might because they're flexing more than the previous tyres because they have more rubber to flex and because the compound is softer
mo didn't tram line, ever, not when new, not when worn out on the edges.
Ao1 train lined from new, and continue to do so. The tread is the same design and depth.
Just seen mo in Costco. Nearly bought some, then remembered they rub very slightly.
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I really do think we have exhausted and discounted every aspect, except the construction of the tyre.
I have seen tyres make a massive difference in handling on bikes. Transforming any Gsxr from a wobbly dangerous mess, to a real weapon (if you like quick steering bikes) just by changing the tyres.
I've also seen the exact same thing in my own previous omega. As others will no doubt remember, fitting worn out Dunlops to replace wobbling and tram lining almost new Falkens.
To see the same problem from another tyre manufacturer in the same model and tread pattern with odds on the same compound, doesn't leave much else IMO.
Al mentioned wwd and rear wheel drive between Audi and merc. ...?
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The front tyres on wwd, and the front suspension for that matter, have alot more asked of them than rwd.
If nothing else wwd geometry will be totally different to allow for the driveshaft which essentially fixes the hub position.
Rwd is much more flexible in this regard.
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I really do think we have exhausted and discounted every aspect, except the construction of the tyre.
Compound hasn't been discounted.
Trouble is, as consumers, we will never be able to find out more specifics about differences between manufacturer specific versions. I'm sure, even if the tyre company was that open (they won't be), I suspect they would be under NDA.
I really do think we are back to finding a suitable tyre that works for what we need, and sticking to it (until its obsolete). Though it can be a bloody expensive process :'(