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So a question from the "new-tire-front-group" to the "new-tire-rear-group"...
Whenever you hear of an accident on a wet road, or see an accident on a wet road, how many times is it someone that's gone off the road round a bend because the rear has broken away and the car gone off the road? Answer: never.
Yet how many times is the accident because someone has hit someone else up the rear end because they couldn't stop in time? Answer: always.
In wet conditions people don't drive too fast round bends. You are far more likely to benefit from the extra grip helping you stop in a hurry. Fact. :)
 

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Boys for the record. I am having my fronts swapped with the rears as we speak with the new ones going on the back. Frankster's no-nonsense intervention swung it for me.

A correction from me where I have been behind the curve is that the ZR rating on tyres are now just R with the speed designation being Y, as with the A45 - up to 186 mph, etc. Although the PS4's still seem to come with the ZR designation.
 

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In one sentence ...

When braking - the rear of the car goes light, if your front is grippier than your rear, your rear will lose grip and *will* come around (provided there is the smallest of sideways influence).

I know, I know, we’ve had enough of ‘experts’ lol


:)
Hehe, Someone needs to tell Audi. They keep putting wider / grippier tyres on the front of RS3. :wink:
 

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Fingers crossed I have only seen (after the event) BMWs having gone into backward motion when it's wet. I have seen it on the M11, M25, M23. So I think the rear grip point is something to heed for beema owners who don't have x-drive.

The only occasions, yes more than once, I have seen it for myself was as a teenager in my Triumph Herald convertible(s), which were older than me. One time there was a sprinkling of snow on the Fulham Road, I was cruising along quite slowly and the car just drifted right across the road and straight down a side road opposite. Incredible luck of no cars and not hitting a building.
 

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You don’t even have to brake, nor wait till it’s wet.

A lift off will provoke the rear to come around, even on a dry road, even on a front wheel drive car, as long as there is a sideways influence ;)

As frankster says, you can’t beat physics.


 

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Of course physics will always be right, but it's a matter of probability, and I'll stand my ground on that one as I know which situation most of us are ever likely to encounter when the roads are wet and we aren't trying to corner too fast!
Anyway many of us have been on the free AMG driving course so know how far we can push our cars regardless of what tyres they have on :)
That fiesta driver got in trouble on a dry road, I don't think deeper treaded tyres would have helped him...
 

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It's good to see he thoughtfully put his hazards on after exiting the road.

That Fiesta may not be representative of those of us passed our teens and early twenties, I bet it had shot tyres. Good remodeled back end too,

But veeeight and Kingpin good points and good videos.
 

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After swapping the fronts with the rears new tyres on the back the tyre pressure warning came on while cruising along the M25. This is after a few day from the swap and probably after around 100 miles. When stopped it asked for the run flat tyre pressure to be reset. I just did an okay on the tyre pressure and reset it.

Is this what we should expect and the reset is the way to deal with it. Why did it come on after 100 miles?
 

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Did you change the tyre pressures so that F270 R220 when cold?

If not you would have put your R220 on the front, and the system would have been expecting to see F270 and so thought there was a deflation.

Not sure about why after 100 miles.
 

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Whenever you hear of an accident on a wet road, or see an accident on a wet road, how many times is it someone that's gone off the road round a bend because the rear has broken away and the car gone off the road? Answer: never.
I've seen this on those Police TV shows where people have gone around a corner at speed and lifted off the throttle instead of stayed on it. They were fatalities too.

Yet how many times is the accident because someone has hit someone else up the rear end because they couldn't stop in time? Answer: always.
You're right I see this all the time, its nothing to do with the tyres though, its the bozo's at the wheels.
 

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Did you change the tyre pressures so that F270 R220 when cold?

If not you would have put your R220 on the front, and the system would have been expecting to see F270 and so thought there was a deflation.

Not sure about why after 100 miles.

Yes it was cold when the tyres and wheels were changed. Are the numbers you are quoting bars without the decimal point.

It seems okay after the reset but I now don't get back from business travels until 23rd September so will see then. I have a service booked in early October in any case so will get any required changes sorted out then.
 

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I realise that this is going the whole way and just fitting 2 winter tyres to the front, but the principles of fitting grippier tyres to the front and not the rear are similar....

Physics in action :)


 

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Wet M62 Motorway

Single vehicle RTC

BMW X3 Rear Tyres below legal limit

Driver most likely lost the rear of the car, with the rear tyres aquaplaning and the car spun round.


 

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A new meaning to going sideways.
 

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Wet M62 Motorway

Single vehicle RTC

BMW X3 Rear Tyres below legal limit

Driver most likely lost the rear of the car, with the rear tyres aquaplaning and the car spun round.


I can see you now, pushing your chest out and holding your head high.......justifiably. Drop mic and walk away!! 😊😊😊😊
 
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