[dxb335d]

How are you guys finding out that there cracked? Loss of pressure?

[M3-FAST]

good idea but add it to the existing thread, otherwise we are just going to have two threads visiting the same topic?

[M3-FAST]

Originally Posted by carrerarsr

I've hit a few pot holes and speed ramps in the last few days. Its always the front that takes the beating in my experience, not the rear!

Its also worth checking out what engines are having the problem. Is it just the 330 and 335's with more power/torque through the rears?

good point - the rears normally take a lot less battering?

All with cracked wheels need to start adding there names to a list - how many people have them???

[tyler durden]

is the thick wall of a RFT on the inside out outer edge of the tyre?

Would swapping out of RFT at next tyre change negate the risk?

[phazon]

Originally Posted by E92 LeMans

I think we should do a poll on cracked 225 ie if you have a car with 225 have they cracked or other answer yes i have 225 but not cracked as this will give us percentage of wheels cracking to number sold.

I think this is a problem for the UK as Msport kits where only sold in the UK as a option most other countries have to by all the option seperatly so cost a fortune

It's not just 225s - mine are 230s, and I know there was at least a couple of others on 230s with the problem.

Lets start the watchdog process - I am happy to help coordinate. Any suggestions as to how we get it moving?

[E92 LeMans]

but it does seem to effect 225 more than anyother wheel.

What i was trying to do is find out the percentage of faulty wheels and did not want to cloud the results with people who dont have 225 's posting for example most people with 17 or 18 are not having any problems. We hear about the people with problems but no one has said mine are fine, thus I am trying to gauge if we have 100 memberswhich have 225 wheels how many have had to replace wheel due to this problem. This is also why i tried to start a new post so it did not get lost in 7 other pages.

Also when you have spent £30+ on a car and once a year you have to spend £500 on new rims I think it might be worth a duplicate thread

[phazon]

Absolutely agree its worth another thread and poll. However, I think it should look at the issue across the 19" alloys, as it is clearly affecting 225s and 230s. I would agree there are more 225s affected, however the problem with the 230s is there and just as valid (and expensive!) an issue.

As I say, happy to help coordinate anything. Somehow we need to get all the affected people's name together and open a Watchdog case

[M3-FAST]

Originally Posted by phazon

As I say, happy to help coordinate anything. Somehow we need to get all the affected people's name together and open a Watchdog case

absolutely - said that yesterday - if everone posts there username and wheel type if they have HAD broken wheels then at least there will be a true figure. Surely there is little point in compiling a list of people who's wheels are OK (at the moment!)

At least then there will be a clear indication of which members are affected.....

Anyone gonna start?

[Gibbo]

I have just read this and thought it was interesting if true. If this is the case then surely run flat tyres are not fit for purpose as they damage the car pernamently and it's a dangerous long term solution to a puncture.



http://www.topix.com/forum/autos/bmw...79AR1LNTAM9LMI

"Hi, despite what many are saying regarding BMW alloys cracking due to pot hole etc it is actually a result of the tyre being driven on flat as soon as there has no air the tyre will rapidly heat up, a conventional tyre would break up and allow this heat to disperse however the runflat tyres dont and as a result the alloy wheels are heated to a point in whick they crack this is a very common problem throughout the bmw range . the tyres must be regulary check for pressure the tyre monitoring rpa system can only detect a sudden lose of air and as tyres loose air over time without having punctures its not easy to see if a runflat tyre is low on pressure "

[xenon]

Originally Posted by Gibbo

"Hi, despite what many are saying regarding BMW alloys cracking due to pot hole etc it is actually a result of the tyre being driven on flat as soon as there has no air the tyre will rapidly heat up, a conventional tyre would break up and allow this heat to disperse however the runflat tyres dont and as a result the alloy wheels are heated to a point in whick they crack this is a very common problem throughout the bmw range . the tyres must be regulary check for pressure the tyre monitoring rpa system can only detect a sudden lose of air and as tyres loose air over time without having punctures its not easy to see if a runflat tyre is low on pressure "

There is lots of bollox on the internet, obviuously, but that's the best I've ever read. The lack of air in the tyre causes it to heat up a 19kg lump of magnesium alloy to the point where it fractures?

[mda335i]

Here's confirmation of cracked wheels I had last year.

Car: E93 335i M Sport
Build date: Feb-07
Registered date: Mar-07

No of wheels cracked: 2 rears - Jun-08 @ 9000miles

Resolution: £600 paid by my insurance / £420 paid by my BMW dealer (after 2 months of complaining)

[robbie99]

Originally Posted by xenon

There is lots of bollox on the internet, obviuously, but that's the best I've ever read. The lack of air in the tyre causes it to heat up a 19kg lump of magnesium alloy to the point where it fractures?

Indeed. That's a load of bollox. Heat has nothing to do with this, although the runflats do makes things worse in that if you hit small pothole (one that wouldn't normally do damage) with a normal tyre, the sidewall will flex and the air cushions the blow. Any impact force with normal tyres is transferred accross the full width of the wheel via the airpressure. With a runflat, the sidewall doesn't flex and some of the impact force is transferred straight up through the sidewall and directly onto the rim, with the blow leading to cracks.

Here's my take on why the rears are more susceptible to the cracking.

1. The 19" alloys (both 225 and 230) are 8" wide for the fronts, 9" wide for the rears. The outer rim (on any wheel) has the benefit of the spokes to keep it stiff and rigid. The further away the inner rim is from the supporting spokes, the easier it is to flex and deform it. Think of a can that has been cut through the middle. If you try to squeeze the base of the can it will hold its shape. Squeeze the cut edge away from the base and not a lot of force is required to bend it. The wider the wheel, the easier it is to bend the inner rim.

2. The rears on the BMWs run negative camber. AFAIK the fronts run zero camber (or certainly much less than the rears). The negative camber places more of the load on the (mechanically weak) inner rim.

Be it brittleness or manufacturing defect, everything else being equal, the mechanics are that it takes far less impact to damage the inner rims on the rears than on the fronts.

[xenon]

^ agreed.

[E92 LeMans]

Originally Posted by redE93cab

absolutely - said that yesterday - if everone posts there username and wheel type if they have HAD broken wheels then at least there will be a true figure. Surely there is little point in compiling a list of people who's wheels are OK (at the moment!)

At least then there will be a clear indication of which members are affected.....

Anyone gonna start?

I agree with what you are saying but what i was trying to do is get a feel for what percentage is failing hence why I started a different thread! Then if 80% of people who own these wheels hav had to replace them then it is a bigger problem than we think!

[vivekk]

Originally Posted by E92 LeMans

I agree with what you are saying but what i was trying to do is get a feel for what percentage is failing hence why I started a different thread! Then if 80% of people who own these wheels hav had to replace them then it is a bigger problem than we think!

Unfortunately, having the same information in a different thread is only of any use if the posts in that thread remain completely on topic- in practice, that just does not happen.

Separating multiple strands concerning the same issue is also a problem, especially when new users post their problems in the wrong one, or worse still, start a new one about the very same topic.
Searching through multiple threads, in order to find information about any specific topic is also a problem for everyone.

For those reasons alone, I'd prefer the information to remain in a single thread, ok.

Also, statistically-speaking, any quantitative data collated in a forum is not of any 'real world' use- sample size is relatively small & the data just cannot be extrapolated properly to relate to the entire E9x-owning population.

Viv

[AlanQS]

Even worse, people tend to join forums like these after they start having problems which means that the numbers having problems are skewed and not representative of the general BMW owning population.

What would be very effective is the number of people who have experienced the problem after joining the forum therefore the problem was not the cause of joining the forum and would be representative.

If for example, 3 out of 20 pre-existing owners with the same wheels developed the same problem, this would suggest some sort of issue.

My twuppence worth.

[five50]

Was disappointed by the response from BMW legal in the earlier post. Not sure of all the facts re the consumer protection act, but seems to be quite a bit of smoke and mirrors there.

The extent to which this is happening at a time when:

"BMW's boss Norbert Reithofer yesterday described the situation to Germany's Spiegel magazine as "the worst crisis BMW has faced in its history"."

May or may not be coincidental...

BMW have done the run out test on my girlfriends car and delivered the same message - that they are not interested in doing anything. To me, the run out test seems a bit pointless - sure, it tells you that the rear wheels may not be true (approx 2mms), but does not establish why this happened - whether due to abnormal driving and potholes or whether the construction of the wheel is substandard.

We've submitted the case to the SMMT and will see what they have to say.

If anyone is coordinating the taking of details to move this forward with a programme like watchdog, very happy to provide info.

This all leaves a pretty bad taste in the mouth. We've paid a lot of money for a car to find out it has substandard quality wheels - both I and she have had different cars from BMW, Porsche and Audi that have been subject to very similar driving patterns and none have had this problem. If we fork out cash to put new wheels on the car ourselves, we have no way of knowing if we are going to be in the same position in 12 months time or less. Do we switch to 18's which seem to avoid the problem - but requires the purchase of 4x new wheels and tyres (rather than 2 wheels) and presumably a reduction in the value of the car?

My girlfriend is pregnant and unsuprisingly, she does not want to drive round in a car with damaged wheels or wondering if the new wheels have gone...

[Neil McRae]

pjs,
You are going to lose this case mate. Sorry but you will.

BMW will put on their highly experienced experts. Magistrate will rule in their favour.

You need an expert, and you also need data.

A good comparision would be to get 25 E46 Sport owners to tell of their lack of cracked alloys, or talk to independant BMW garages, and get 25 current E9X owners to note that they have had cracked alloys. Then get an expert to confirm this issue.

Neil.

[Neil McRae]

but also may be worth to raise a claim against your dealer.

[Neil McRae]

oh and I have an E61 sport. I lost the tyre of my wheel when the runflat went flat but the system didn't warm me. Lost it at 60MPH. Replaced the tyre but it continually went down, got a new wheel of ebay.

[big pimp]

i am still with you on this PJS, and I still have my 2 cracked rear wheels to supply if you need them, along with my 4 tyres - the 2 rears shredded with less than 7k on them due to camber being so badly out!

[COLSEN]

Originally Posted by pjs

You might have seen my cracked wheels thread elsewhere, this is a new one to keep it brief and simple. A few of you have been asking how I've been getting on

Long story short is that I've simply had two cracked rear alloys - Scothall and BMW cust services refuse to cover under warranty. Threatened BMW with legal action should they not resolve to my satisfaction, got ignored.

Just done the claim online whilst watching spooks, pretty simple, £60 cost.

Feel free to guess if I will suceed or fail....

Oh, and if anyone from BMW customer services is reading, good evening....

I think we're slipping away from what PJs is asking. It isn't rocket science, if you have a damaged 19" alloy, let him know, if it's happened to a lot of wheels, the greater the chance of getting this sorted under warranty. I try to avoid pot holes on my 225s, but still, I'd be annoyed if I was told I needed a new alloy for driving over a pot hole... I never had this problem in my corsa!!