Where to put new tyres?

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adamskibx
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Post by adamskibx »

When I had my Dyane I went into a tight slip road bend too fast (first and only time I forgot it was wet on the roads!) . It oversteered dramatically and I went all the way round the bend on opposite lock- In a 2CV this never happens- Its the front that goes- Just the slight extra weight of the rear metal hatch over the 2CV's halve vinyle back was enough to upset the balance- The Dyane was always more fun though and never caught you out as it always happened very slowly.
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Post by oilyspanner »

Mind you the best place for worn tyres in in a skip, having just splashed out on a set of half decent rubber for the BX its really noticeable how poor the old ones were even though they were still (arguably) legal when removed.
Stewart
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Post by yangreen »

My Audi 100 (1987, new toy) handbook states that new tyres should always be put on the front. This being a front wheel drive car. I ALWAYS put new tyres on the front.
Regarding oversteer in 2cvs, had one alarming experience which turned out to be a flat tyres. Opposite lock held the skid. Easing off brought it back in line! I'm sure that's not how it is meant to happen...
Had a few moments where the back end of my 306 stepped out but application of power and easing off the lock always brought it back under control. Wasn't quick enough when it happened in my Subaru though...
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Post by FrenchLeave »

Reference aquaplaning. There is a simple formula to calculate the speed (in miles per hour) at which aquaplaning will occur with smooth tyres on a wet road, it was introduced for the benefit of aircraft operators and is:
Aquaplaning speed = nine times the square root of the tyre pressure.
For treaded tyres it depends upon the depth of standing water and the tread's ability to shift it, but will never be less than that for smooth tyres. So with 25 psi in your tyres you should never aquaplane below 45 mph.
Ain't science wonderful?
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Post by Kowalski »

They don't need to fully aquaplane for a disaster to happen, they just need to produce enough of a reduction in grip so the back end of the car slides.
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Post by drpau »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by RichardW</i>

Understeer: The car crashes through the hedge forwards
Oversteer: The car crashes through the car backwards
[:D]
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
That is possibly the best desription of them Ive ever seen! [:D]
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Post by bxbodger »

People may think aquaplaning is a thing of the past cross-ply age, but it can and does still happen with radials, and is common abroad in Europe!!!
Its not a problem of tyre design or bad driving technique but of road design- inadequate surface drainage, and a lot of Belgian and French roads are prone to it, Belgian motorways in particular have long sections where you are warned of the danger of "aquaplanage", complete with skidding car symbol.
I had it happen once in a torrential downpour on an Italian autostrada in august 1987 and it was a truly terrifying experience-I can remember it like it was yesterday- there was no warning, it was instant and the car just went light and floaty and I knew I had no control whatsoever[:0][:0]: foot off the gas is the way to deal with it and you get back control as the speed drops, the tyres start to shift water, and as long as there's nothing in the way-there wasn't and I never want to experience it again!!!!!
One of my friends whose wife is German was on his way back to England last year with her and their two kids and his dad in the car when he started to aquaplane in the middle of the night on a bend- the car, an Escort, had 4 nearly new tyres but it still happened, they hit the barrier, and the car was written off- luckily apart from him they were all asleep so didn't see it coming and were relaxed, but they were very lucky to walk away!!!
Aquaplaning is why F1 cars crash in the wet- they may be top drivers but once it starts they have no more power to stop it than us mortals- its wht Shumacher is so good in the wet- he seems to be able to see it coming better than the others and hence never get into an aquaplaning situation!!!!
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Post by oilyspanner »

Yes Aquaplaning is certainly likeley to cause an anal pouting session, wide tyres make it worse too, worn wide tyres and you are away, returning from Scotland last summer ther was a torrential downpour, the motorway slowed to 45 mph apart from some teutonic motors who obviously thought they were immune, scratch one 3 series bimmer and an A4.
Stewart
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Post by Kowalski »

Is the ultimate driving machine also the ultimate crashing machine?
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Post by oilyspanner »

It had a good run along the steel post/cable type barrier favoured north of the border and looked like a giant can opener had been at it[:I]
Stewart
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