Span 180 degrees today

[James]

Will try that Nuster.

The outside line of the rear tryes are worn more than the inner 2 suggesting over inflation but on last check they were correct pressure and 2 psi less than the fronts. (fronts being 36).

The geometry or tracking has never been done, the wheels have been balancd by a spanner monkey at kwik fit at various stages but I dont trust them with a barge pole.

No sounds or creaks, no potholes hit or noticeble issue. In the dry there is no issue.

Having just been outside to clean the car and almost fallen over with the water turning to ice under my feet I think I have just been unlucky. The roads yesterday were about the worst I have ever experienced, they were like shiny mirrors of ice.

[nuster100]

Other thing that didnt help was the liner used to run -1 degree camber on the rear. Have vauhaull done something similar to get 19" wheels under the arches?

Jay

[Red Herring]

You may also want to consider the temperature your tyres are running at. Big low profile tyres on light cars are notoriously hard to warm up or keep any temperature in and performance tyres in particular have fairly narrow envelopes. That might explain why the Micra on it's skinny hoops stayed on line......

[jcochrane]

Last time I had a problem with the back end of the car behaving in a strange way I just could not figue it out. Everything looked fine until I got it up on a ramp, then the problem was obvious, there was a nasty bulge on the inside of one of the rear tyres. Once replaced the car was fine again.

Have you done any mods. to stiffen up the rear of the car? An over stiff rear end can be interesting on a slippery road surface.

[Red Herring]

An over stiff rear end can be interesting on a slippery road surface.

I've always found a slippery surface tends to loosen up the rear end a treat....

[James]

No mods at all to the rear. But it feels stiff from the drivers seat.

Interesting comment about the heat and condition of tyres. No bulges that I have noticed.

[Renny]

James,

I'd look at swapping the tyres front to rear as you mentioned, or if the budget allows, fit a pair of new tyres. It may be that the old ones are past it (aged and hard rubber) and marginal for grip in the cold conditions. A pair of tyres may be cheaper than your insurance excess ...

[James]

Oh my god!

I have just had a messae come through via my youtube account from a girl called Emilia saying "saw you lose control yestrday off the a3 were you ok?"

What is going on!!! Is this a conspiracy from god or something rofl

[waremark]

If you hit the kerb now you have to get the geometry checked as well as having a wheel off look at the tyres.

High performance tyres may not be great on cold roads but they should not be this bad (just changed my rears at 2mm after Monday at Bruntingthorpe - have not experienced any problems).

If I was you before changing the tyres I would get myself onto an airfield perhaps with Andy Walsh or Don Palmer or equivalent to explore lift off oversteer and how to control it in your own car.

[Daaave]

Given your description, I'd get the following things checked:

1. Alignment. Don't go to a dealership or your local Kwik-Fit - go to someone with a proper 4 wheel alignment rig. Wheels in Motion in Hemel Hempstead is a good place to go to, or if you ring Tony there, he'll recommend somebody local who knows what they're doing. I don't think there's much adjustability inan Astra VXR, so if something is seriously wrong then it'll be new component time. It's entirely possible you'll have bent the rear axle beam which has some interesting effects on handling (Last one I investigated resulted in a 20 car pile-up on the M40 when the right combination of speed and turning happened)

2. Tyres. I doubt they're the cause but arsing around with tyre pressures isn't going to cause the major l-o-c you've described. But it's a good idea to exclude them.

I can't echo Dave's advice enough. I didn't have quite the same degree of trouble, but a visit to Wheels in Motion to have my geometry re-set (it was pretty far out even after a visit and adjustment by a 'Pirelli Performance Centre' tyre dealer) and a new set of rear boots sorted out my strange rear end twitch.

[waremark]

4. The driver... Don't get all huffy with me, but I've driven with plenty of Police drivers and the cornering style they're taught can be a contributory factor.

I waited a day or two for someone else to ask you to clarify this comment but no-one has! Will you?

[waremark]

Police drivers tend to be a little abrupt in their application of steering (and rarely if ever 'hint') so they have a slightly higher probability of having an imbalance on first steering which can increase the risk of loss of control. It's a tiny thing, but noticeable when you're looking for it.

Since we are talking about lift-off oversteer here, I thought you might be suggesting that they tend not to be on the gas as they corner, which would be contrary to Roadcraft. Obviously I was on the wrong track.

James do let us know how you get your car checked and what the findings are.

[Red Herring]

Police drivers tend to be a little abrupt in their application of steering (and rarely if ever 'hint') so they have a slightly higher probability of having an imbalance on first steering which can increase the risk of loss of control. It's a tiny thing, but noticeable when you're looking for it.

Should we start another thread to expand on that because it's a pretty bold statement. I would have thought keeping the balance on a vehicle going into a corner would be pretty high on a police drivers list of priorities and would be fairly surprised if their training had a tendency to not encourage this. What would be the possible advantage to not "hinting" that encourages police instructors not to train it?

[James]

Have missed lot of the the last posts.

Whats hinting?

[waremark]

Have missed lot of the the last posts.

Whats hinting?

You may think of it as turning the steering wheel progressively.

When you start to turn the wheel you are turning the tyres but there is a short delay as the tyres load up before the tyres start to turn the car. The technique of hinting involves applying a tiny amount of steering early before you are ready to start the car turning in order to 'preload' the tyres.