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[Kevin Wood]

However I do wonder, as cem mentioned, and given the MO sc3 tyres performance, if tyres that work on Mercs would also work on the omega. Maybe...?

Mercs of a certain era have much worse set up than an omega, with massive castor angle and aggressive camber that's non adjustable.

That's a good point. The Omega's suspension is clearly a factor in whether a tyre works or not, hence tyre reviews not being worth reading, IMHO. If the merc shares the Omega's sensitivities then perhaps there's some information that can be gleaned from that if Merc have gone to the trouble of doing the research for their specific setup.

Oh, and, IME, if tramlining is an issue, it's there at all speeds. Possibly greater at lower speeds, even?

[Auto Addict]

I started off with Michelin Pilots on the 2.2, no tramlining, then Kumo Sports, still no tramlining, but it had the 'wanderlust'.

Can't remember what was on the 2.6, but it tramlined, changed to Kumo Sports, and it still tramlined, but it didn't 'wanderlust'.

The Astras' got Contis on and doesn't tramline, the Insignia's got Bridgestones and doesn't tramline, neither 'wanderlust'.

[kevinp58]

What wheels are they on? 225/45/17 isn't an Omega size

 I know that 225/45/17 are NOT standard tyres for omega but if you read my comment properly the wheels came with the tyres already on  they were good tyres so I thought I would use them instead of binning them  the wheels are standard Omega Elite 17" wheels and not from Insignia or any other Vauxhall.
I have just had a thought that because most new cars today are funny wheel drive instead of real wheel drive  are the tyres being made to perform differently and not brilliant for older RWD cars.
 And BTW its a FL and not a PFL as stated sorry. 

[feeutfo]

Can I ask what kind of speed you are doing for this to happen, are we talking 60 to 70 or are you "pressing on" shall we say. I ask as wondering if aerodynamics are coming into play. Less than 70 and aero has little effect. above 70 and it comes into play. Virtually all road cars produce lift, could it be going light at high speeds ? This could be a design problem.

If you look at the side profile of the Omega it is basically a wing. So at high speed you will have low pressure on the upper surfaces of the car.

Just a thought.

some people seem to notice it more than others, but ime speed is not a factor. For instance width restrictions can be a right royal pita, where every vehicle has to pass over the same piece of Tarmac, hence a pair of wear lines appear where the Tarmac compresses. It's obviously negotiated at walking pace.

There's a wr in Reading, near cow lane bridges, locals might know it. The the far side has two exits, you can turn left or right immediately after the restriction which is about 6 feet long. So you  get a YY tram line on the exit. This involves steering wheel corrections ranging from 9 o'clock to 3 o'clock with the steering wheel in order to avoid hitting the kerb with 912 fitted. Mo are unaffected iirc.

[feeutfo]

At the other end of the speed spectrum, motorway speeds where restricted to about 8mph due to width if the lane. And that was being brave.

Mo go on unhindered.

[05omegav6]

I am in two minds as to weather to enjoy the day blasting round, or with pen and paper making notes.

I suspect, however enjoyable the former could be, the latter would still be a day well spent, being an almost unique opportunity to compares tyres and suspension set ups on several Omegas

[TheBoy]

Can I ask what kind of speed you are doing for this to happen, are we talking 60 to 70 or are you "pressing on" shall we say. I ask as wondering if aerodynamics are coming into play. Less than 70 and aero has little effect. above 70 and it comes into play. Virtually all road cars produce lift, could it be going light at high speeds ? This could be a design problem.

If you look at the side profile of the Omega it is basically a wing. So at high speed you will have low pressure on the upper surfaces of the car.

Just a thought.

Probably noticible from 40ish?  Upper end, dunno, my balls aren't big enough with those tyres. Certainly into "instant ban" territory.

[Lazydocker]

Can I ask what kind of speed you are doing for this to happen, are we talking 60 to 70 or are you "pressing on" shall we say. I ask as wondering if aerodynamics are coming into play. Less than 70 and aero has little effect. above 70 and it comes into play. Virtually all road cars produce lift, could it be going light at high speeds ? This could be a design problem.

If you look at the side profile of the Omega it is basically a wing. So at high speed you will have low pressure on the upper surfaces of the car.

Just a thought.

Probably noticible from 40ish?  Upper end, dunno, my balls aren't big enough with those tyres. Certainly into "instant ban" territory.

Man up wet pants... Where's your sense of adventure

TBH, if Mrs TB notices it then it can't be because the car is being driven far too fast

[feeutfo]

At the other end of the speed spectrum, motorway speeds where restricted to about 8mph due to width if the lane. And that was being brave.

Mo go on unhindered.

80mph. Not 8mph.

[2woody]

as an experiment, have we tried some "very tramlining" tyres on a car which doesn't do it.

tramlining is classicly defined as a poor reaction to road camber chages which results in a net steer effect.

things that make it worse are generally :-

wide, low-profile tyres. The wider and the lower aspect the worse it gets
poor chassis set-up. the vital adjustments and bush condition
poor suspension design. steering box, for example.
tyre construction and age

its not very difficult to get all of these in an Omega B

[2woody]

just a thought - do these tramlining cars all have the harder ( BMW ? ) bush in the wishbone ?

[TheBoy]

Man up wet pants... Where's your sense of adventure

The desire not to die just yet. There is a limit to how strong my arse cheek muscles can clench. Additionally, currently running at low pressures, so concerned with sustained high speed stints.

[TheBoy]

as an experiment, have we tried some "very tramlining" tyres on a car which doesn't do it.

tramlining is classicly defined as a poor reaction to road camber chages which results in a net steer effect.

things that make it worse are generally :-

wide, low-profile tyres. The wider and the lower aspect the worse it gets
poor chassis set-up. the vital adjustments and bush condition
poor suspension design. steering box, for example.
tyre construction and age

its not very difficult to get all of these in an Omega B

Yes, swapped between my 2 Omegas. Tramline moves with the tyres, and the original tramlining car drives straight with different tyres. The tramlining started with the fitting of these new tyres.

Hence the feeling is that there is something about these tyres that make them unsuitable for Omegas.

[2woody]

both omegas on the same size tyres ?

[2woody]

certainly the tyre compound and tread pattern will have an effect.

in order to deflect to absorb the camber, the tyre would really need to be quite soft with a tread pattern able to move around a lot. Pattern a might not be as good as pattern b. then again pattern a when old might be better than pattern b.

I'm sorry, but all of this comes as no answer for someone with a tramlining car.