[HighlandPete]

Originally Posted by dib669

My wife's 330i has gone through three sets of RE050A* rears in 15000 miles (as well as four rear 225M rims). Each set has had the same problem described here - the inner edge (about 10mm wide) down (or nearly down) to the carcass with about 5 - 6mm rubber left over the rest of the tyre. I've heard that Bridgestone have changed the compound on the inner edge of the RE050s to try to compensate for whatever's happening. Anyone else heard this? The car, much as I like it, is going soon for this reason.

Why? Surely a bit of revised geometry and fitting decent rubber is the solution. Each to his own.

HighlandPete

[acerboo]

mine were the same at 20,000 miles, bridgestone blamed me for running the tyres below pressure and overloading them (i know of at least one other person they did the same to) which is absolute bullshit and an insult! i check the tyres weekly and keep them spot on, no the problem is their crappy tyres, anyway once bitten as they say.

[Arch Stanton]

i went for a little trundle out today, not spirited by any means, too much traffic so a gentle ride out. Due to threads such as this i decided to check the condition of the inside shoulder of the car and the shoulders were noticeably warm. Cold wet roads, gentle drive and the shoulder was worked enough to get heat into it. The rest of the tread footprint was cold, as I would expect it to be. I think next time I get new tyres on I'll be asking for the -ve camber to be dialed out. The effect on handling will be minor, hopefully the savings on rubber will be major!

Arch

[HighlandPete]

Originally Posted by Arch Stanton

i went for a little trundle out today, not spirited by any means, too much traffic so a gentle ride out. Due to threads such as this i decided to check the condition of the inside shoulder of the car and the shoulders were noticeably warm. Cold wet roads, gentle drive and the shoulder was worked enough to get heat into it. The rest of the tread footprint was cold, as I would expect it to be. I think next time I get new tyres on I'll be asking for the -ve camber to be dialed out. The effect on handling will be minor, hopefully the savings on rubber will be major!

Arch

The heat values are something I experimented with about 3-years back, when I was having major issues with run-flat tyre performance. Very odd heat patterns when you run your hand over the tyres, for different trip distances and ambient temperatures. You certainly run on the inner sidewall and get extra heat, compared to a conventional tyre doing exactly the same trips.

What I also found, tyre pressures make a lot of difference. Where normal rubber at a lower pressure deforms more and therefore can spread the load a bit better, the run-flat will ride on the sidewall and make local wear even worse. A bit more pressure and we start running more on the crown of the tyre and don't get so much of the inner shoulder heat. The heat is spread more across the tyre as you'd expect.

The other observation through experiment, the tyres don't warm as fast as normal rubber, so we don't get up to working pressure as fast, many more miles on the sidewalls, if our setting pressures are 'normal' (or low) and accelerated inner wear results. Same for the outer front shoulders, as they also suffer extra sidewall loading until running full working temperature and pressure. Plus there is an extra cooling factor on the front outsides, contributed to by the front skirt/apron shaping. Just take a look from the front of the car and see the exposed shoulder.

Now factor in the extreme cambers on some models, add the bigger rims and we have a recipe for even faster tyre wear.

Common sense teaches us that less negative camber, smaller rims with more rubber to distort, keep the tyre/rim widths down, have more supple tyres, all contribute to parameters where tyre wear can be normal and much more even.

HighlandPete

[Jules6]

I have 19s on my E92 and have found that running 5psi higher all round has made a significant improvement on tyre wear. Or is it that Bridgestone have changed the compound?

[HighlandPete]

Originally Posted by Jules6

I have 19s on my E92 and have found that running 5psi higher all round has made a significant improvement on tyre wear. Or is it that Bridgestone have changed the compound?

I'd suggest the pressures are making a big difference, I increased my fronts by about 4 psi and the rears by about 3 psi, that helped the wear rates, even on 17" tyres.

Not many users state what pressures they are running, BMW know a lot of folks don't check, or keep a close watch on tyre pressures.

HighlandPete

[Jules6]

On my E92 325d (manual gearbox) the standard pressures for the 19s for light loads is 2.4 bar front 2.6 bar rear, so I run 5psi above those (about 0.35 bar)

[valor]

Hi all,
I found this thread through google
I'm experiencing the same trouble on my rear 19' wheels.
I wonder if any new solutions found, other than altering camber or adding more pressure?

Some photos

[Expatmick]

Just put the third set of tyres on my 335 d touring, only done 26000 mls. Mine have gone down to the canvas on the Front outside edge each time.

Took it to a BMW dealership to replace the rubber and check the alinment, they did not even want to do a check as they reckon it`s the norm on these cars. HOW CAN THIS BE RIGHT, you have plenty of tread left on the rest of the tyre and the walls are shot. This little trip cost me over £1200.

Trouble is the car is brilliant in every way.

[xenon]

Mine are just like that photo - perfectly serviceable apart from the inner edge. You have to throw them away and fork out an eye-watering £270 for each. BMW say there is "no issue here". Bastards.