[M3-FAST]

Originally Posted by gIzzE

The whole point is to use your existing tyres to save money yeah??
Well I would say you would be much better off selling your rims with the tyres on them and buying some reps, even the cheapest non run flat will be better than what you have now.

You could get good money for OEM 19" rims, certainly enough to pay for some decent reps with something like Falken FJ452s fitted all round and a compressor and can of tyre gunk.

I would do that if I could!! The car is financed on a 2 year lease deal and need to go back with the original wheels on.

I may just do as James says - buy a wheel/tyre package and remove my wheels, stick em in the garage and fit em before the car goes back. Prob wont be much worse off long term as normal tyres seem to be lasting longer than runflats anyway. I may end up getting new runflats during the lease, wheras some normal non RFT may last the course. I am on a 10k pa deal but as the car spent so much of its first few months in the garage it only has 4k miles in the first 7 months so I am well under mileage!

I do appreciate all the comments tho guys, really does give you food for thought

[gIzzE]

Definitely do that then, if you return a lease car with less than 3mm they will charge you for a new set of tyres, so best to buy some proper tyres now.

[E92Fan]

You CAN install, but SHOULD NOT use standard type RUNFLAT tyres on a NORMAL alloy wheel which is not designed for the runflat type tyre. An alloy wheel designed for runflats has an extra locating ridge to secure the tyre in the event of a blow out. That menas that you can drive on a blown runflat safe in the knowledge it will not dislocate itself off the wheel.

Putting a runflat on a NORMAL alloy wheel without this locating ridge is a recipe for disaster, as you will be led to believe that you can still drive on the tyre as it stays in shape, which is true, but you have no protection on any lateral movement of the tyre on the rim. The tyre will work, but will not offer the "get-you-home-safely" advantages of a complete runflat system (ie wheel AND tyre)

The reverse scenario shows no problems - any wheel can support a standard NON-RUNFLAT tyre.

[NFS]

Originally Posted by E92Fan

You CAN install, but SHOULD NOT use standard type RUNFLAT tyres on a NORMAL alloy wheel which is not designed for the runflat type tyre. An alloy wheel designed for runflats has an extra locating ridge to secure the tyre in the event of a blow out. That menas that you can drive on a blown runflat safe in the knowledge it will not dislocate itself off the wheel.

Putting a runflat on a NORMAL alloy wheel without this locating ridge is a recipe for disaster, as you will be led to believe that you can still drive on the tyre as it stays in shape, which is true, but you have no protection on any lateral movement of the tyre on the rim. The tyre will work, but will not offer the "get-you-home-safely" advantages of a complete runflat system (ie wheel AND tyre)

The reverse scenario shows no problems - any wheel can support a standard NON-RUNFLAT tyre.

I'm not convinced that this is correct. Bridgestone state that their runflats can be fitted to any rim.

Where did you get this information?

[kend]

I have the standard style 157 wheels with runflats fitted as supplied with the car, I picked up a spare rim as I am thinking of changing to non run flats. I can see no extra locating ridge inside the rim. I would post a picture if I knew how to do it as this would help to explain it.
Ken

[E92Fan]

Originally Posted by needforspeed

I'm not convinced that this is correct. Bridgestone state that their runflats can be fitted to any rim.

Where did you get this information?

That is strange, because I got that information from Michelin UK directly... perhaps the very latest iterations of the runflat tyre now support standard alloys? Doesn't make sense though, because if there's no extra ridge, then how does a 'blown' runflat stay on the wheel at speeds of up to 50mph and going round corners? Sure the sidewall is stiffer, but there will be increased lateral movement as the Michelin people told me

Will check again today and report back...

[NFS]

Originally Posted by E92Fan

That is strange, because I got that information from Michelin UK directly... perhaps the very latest iterations of the runflat tyre now support standard alloys? Doesn't make sense though, because if there's no extra ridge, then how does a 'blown' runflat stay on the wheel at speeds of up to 50mph and going round corners? Sure the sidewall is stiffer, but there will be increased lateral movement as the Michelin people told me

Will check again today and report back...

There is some useful info on wikipedia.

The Bridgestone RE50s are 'self supporting' as described here:

http://en.wikipedia.org/wiki/Run_flat_tire

This is Bridgestone's RFT site:

http://www.runflat-system.com/index_en.html

The beads on the tyre are wider than for a non-rft, which keeps them on the rim. The wheel itself is standard.

Pirelli RFT's are also 'self supported':

http://www.pirellityre.com/web/car-s...t/default.page

The Michelin PAX system is 'auxilliary supported' so it has a special wheel AND a supporting insert:

http://www.familycar.com/CarCare/RunFlatTires.htm

However, the PAX system isn't used on BMW's, so if you have Michelin RFT's on they will also be self supporting:

http://motortorque.askaprice.com/new...get-a-grip.asp

[M3-FAST]

Superb info guys - never thought of looking at Wikipedia to be honest!!

It does seem then that whichever option I choose with the tyres (ie: use my own or but a wheel/tyre package) won't make too much difference.

Just need to be nice to the miswah before I drop the 'these wheels would look nice on the car love......so I bought 'em! '

[Hotcoupe]

E92Fan Quote:
Originally Posted by needforspeed
I'm not convinced that this is correct. Bridgestone state that their runflats can be fitted to any rim.

Where did you get this information?


That is strange, because I got that information from Michelin UK directly... perhaps the very latest iterations of the runflat tyre now support standard alloys? Doesn't make sense though, because if there's no extra ridge, then how does a 'blown' runflat stay on the wheel at speeds of up to 50mph and going round corners? Sure the sidewall is stiffer, but there will be increased lateral movement as the Michelin people told me

Will check again today and report back...

Tony, I was led to believe by my local tyre guy that wheels designed for runflat tyres have a wider supporting ridge then standard wheels.
Runflat tyres have a wider lip then standard tyres.

That's the info I was given anyway

[NFS]

Originally Posted by Hotcoupe

Tony, I was led to believe by my local tyre guy that wheels designed for runflat tyres have a wider supporting ridge then standard wheels.
Runflat tyres have a wider lip then standard tyres.

That's the info I was given anyway

The tyre bead is definitely wider, so any wheel would need to have a flat ridge for it to sit against.

But I would be pretty certain that any wheels which can take runflats (i.e wheels which can take wide low profile tyres) will have a wide enough ridge anyway.

There certainly don't seem to be any run-flat specific wheels on the market.

Also, when runflats were introduced to the e60 part way through production the wheels were not changed.

[Hotcoupe]

redE93cab Just need to be nice to the miswah before I drop the 'these wheels would look nice on the car love......so I bought 'em! '

Alternatively,put the trousers back on and buy them

needforspeed Quote:

The tyre bead is definitely wider, so any wheel would need to have a flat ridge for it to sit against.

But I would be pretty certain that any wheels which can take runflats (i.e wheels which can take wide low profile tyres) will have a wide enough ridge anyway.

There certainly don't seem to be any run-flat specific wheels on the market.

Also, when runflats were introduced to the e60 part way through production the wheels were not changed.

+ 1.

[Serjames]

lol Ian you're my hero !!



SJ

[M3-FAST]

Originally Posted by Hotcoupe

Alternatively,put the trousers back on and buy them



+ 1.

I get an easy life really - my comments are pretty much tongue in cheek but I like the humour, lol