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[Lagondanet]

Pumped up the tyres. Amazing what a difference it made. 

[VXL V6]

Ordered two bolts..... For a SEAT! 

[RobG]

Replaced front & rear pads

[tidla]

Replaced the front brake pads and discs with ferodo premier (we will see),fabricated a bit of a dust shield in the hope of improving inner disc corrosion.

Ns and os outer track rod ends and tracked up.

Rear discs off and cleaned up on the handbrake surface and greased up adjusters. Give the caliper pistons a work out and a bleed all round.

Treated the inner edges of the rear arches in the vain hope it wont reach the outer paintwork.

Found a busted rear spring..

[chrisgixer]

Pumped up the tyres. Amazing what a difference it made. 

Took a couple of psi out of mine. It's gone all harsh in the colder temps.

[Entwood]

Pumped up the tyres. Amazing what a difference it made. 

Took a couple of psi out of mine. It's gone all harsh in the colder temps.

That makes no sense at all .. as the temps drop the pressures drop anyway ...

The TPMS actually had a bleat again this morning... reckoned the two nearside tyres were underinflated, they were showing 3 degrees 29 psi (warning set at 30 psi) while the offsides were 9 degrees 34 psi ... guess which side the sun was shining on !!

On a more serious note, I have been watching this over the past couple of weeks, as I am surprised just how big a change in pressure a few degrees of static tyre temp causes.... once motoring on dry roads the temps rise to around 10 degrees within about 5 miles and the pressures all sit at 35, however if it is wet the temps hardly move and the warning persists. I have had to take the caps off and inflate all the tyres by a tad twice since september to achieve the steady 35 psi after warm up.

[chrisgixer]

Nout to do with air pressure, and everything to do with poly compliance at various temps.

[omega3000]

Re badged it 

[Entwood]

Nout to do with air pressure, and everything to do with poly compliance at various temps.

ahh so compensating for stiffer poly's by making the sidewalls softer .... not sure that's a good compromise regarding tyre performance .. but your choice of course ...

[chrisgixer]

Nout to do with air pressure, and everything to do with poly compliance at various temps.

ahh so compensating for stiffer poly's by making the sidewalls softer .... not sure that's a good compromise regarding tyre performance .. but your choice of course ...

Was running 34, so room for softer manouvering.  But more heat in the tyre won't hurt either.

Must say I'm suprised how much ambient temp affects the poly's. Straight line accuracy seems the same ( poor ) but ride quality varies a lot. Noticeably softer above 20/23c. Iirc.
Noticeably harsher below 10c.

[Diamond Black Geezer]

Now that's interesting - because over the last week or two I've noticed the turbo weasel seems to be crashing over the bumps a bit - I can appreciate a softer ride feeling more like a bouncy castle being worn shockers, but stiffer ride... why? Colder weather is logical 

[Marks DTM Calib]

The rule of thumb was always 1.5 psi pressure change for every 10 degrees C of temperature change.

Polyurethane is generally more stable with respect to hardness over temperature when compared to rubber.

[Kevin Wood]

Yep, the rubber in the tyres will be less compliant at low temperatures, although they'll warm considerably once on the move. Shock absorbers will also offer more damping when the fluid inside is cold, of course. Pretty much everything will move towards less compliance in the cold.

.. and more power from the engine can often make this all the more apparent.

[chrisgixer]

It's not to do with side wall depth either, just as a note. As it was the same with the Oe wheels on for about a week, and the softer ride was noticeable when Ambiant rose 10c on that week from a wet spell to hit spell.

I spent a good while pondering why the change in ride in the summer last year. It wasn't until fitting poly donuts, to go with the existing front poly, that the effect was doubled and the penny finally dropped.

It IS the poly getting softer with heat and harder with cold. Over and above the nomal seasonal changes we are all aware with rubber.

I was expecting poly to be more consistent. Incorrectly though, as its poored into a mould when hot in production, and can be drilled and machined when frozen. However briefly, until machining causes friction and heats it up again presumably.

[Andy H]

My theory is that the harsh ride in cold weather is caused by the viscosity of the damper oil.