Run flats

[Tyreman]

That old one " Bmw " " the car company that never gets it wrong "

the company that thinks 18k is ok for service intervals on performance cars
the company that thinks fitting runflats is acceptable on a 330bhp 2 seater sports car ( but never on ///M cars :wink: )
the company that fits 255 30 19 runflats onto 9j wide alloy rims that then split due to oe PSI of 44 )

Once you start believing the big names & never question then its game over , they aren't infallible by a long way

I don't have to question anybody on this one, after over 30 years experience in the tyre industry and knowing the differences in construction and the effects on the "unsprung weight" you absolutely should not mix them..........end of story.......anyone with a different view to this is simply wrong !

As with most things tyre / wheel related there are so many variables out there to say 100% that it would be any more dangerous than the car behind you or in front of you .
One might be a £500 Peugeot 106 with 4 non runflats all different brand with mixed asymmetric & directional ranging from 2mm to 8mm & all different pressures . Op on the other hand with his prestige german quality built sportscar might have quality tyres albeit runflats on the rear , non runflats on the front but very good ABS & TC :? i know which one id rather cover 300 miles in

What you say is perfectly true and it has to be said that the tyre law in the U.K is woefully inadequate due to the fact that the government relies heavily on businesses and the general public following recommendations rather than suitable legislation.

We have a tyre law allowing 1.6mm over 75% of the tread width with the remainder allowed to be devoid of tread, we allow the mixing of directional, asymmetric & composite tread patterns.

We import tens of thousands of part worn tyres from other parts of the world with more stringent regulation than our own, however the question here is should the op mix runflats and normal pneumatics and the simple answer is no.

Legally he can but that doesn't mean that he should do so

 

[ronk]

As a personal choice, I don’t even mix tyre Brands or Types.
There’s a lot of testing that goes into tyre Technology - Tyre manufactures spend a lot of cash to test and measure these results - friction, slip angles etc., so while driving like miss daisy nothing will be noticed - but push on a bit ...?

 

[Smartbear]

As a personal choice, I don’t even mix tyre Brands or Types.
There’s a lot of testing that goes into tyre Technology - Tyre manufactures spend a lot of cash to test and measure these results - friction, slip angles etc., so while driving like miss daisy nothing will be noticed - but push on a bit ...?

Yep, I’ve done that a few times Ron & I’m still here to tell the tale
Rob

 

[flybobbie]

I ran mixed for a few weeks, the car steering dreadfully. Glad to get rid of the RFT.
The RFT were trying to tram line and the non's just went with the flow. Strange feeling.

 

[ronk]

This might be old ground but the Bridgestone runflats on the E85 were scarey but on both E89 (3.0l and 35is) I can’t complain. The ride is ok and no tramlining.
Pot holes are the only headache.

Ps.
I know I’m in a minority

 

[Busterboo]

alloy rims that then split due to ... PSI of 44

Tyres split alloys? Yeah, right.

 

[mr wilks]

alloy rims that then split due to ... PSI of 44

Tyres split alloys? Yeah, right.

Tyre type , size & pressure would increase or decrease chances of splits :? Or would you say only a deficient rim is the cause of splits ?

 

[Busterboo]

I don't know and you don't, either.

 

[obewan]

This might be old ground but the Bridgestone runflats on the E85 were scarey but on both E89 (3.0l and 35is) I can’t complain. The ride is ok and no tramlining.
Pot holes are the only headache.

Ps.
I know I’m in a minority

Minority +1 ronk
I'm with you :exitright:

 

[Busterboo]

This might be old ground but the Bridgestone runflats on the E85 were scarey but on both E89 (3.0l and 35is) I can’t complain. The ride is ok and no tramlining.
Pot holes are the only headache.

Ps.
I know I’m in a minority

Minority +1 ronk
I'm with you :exitright:

Well, that's saved some money, then.

 

[Silverzedtom]

I’d only ever run four of the same myself. Can’t see there being any real risk in mixing as long as they are matching on each axle. I would be asking myself if I wanted to give up handling in favour of a little cash... seems a shame to stick runflats on a sports car.