BMW Tyre Wear - Paul F
A friend runs a G reg. bmw 735i SE (150,000 miles & picked up for next to nothing) He has recently noticed a bald patch appearing in just one area on the outside edge of the front offside tyre. The tracking is fine & no wheel imbalance can be felt through the steering wheel. This has us both stumped. Any suggestions would be most welcome.

Paul F.
BMW Tyre Wear - Peter D
The tyre may have been damaged either it hit some debris on a road or has been heavily curbed. The damage may well be in the inner layers of the tyre or even on the inside. The resulting slight bulge has caused that area to wear rapidly. I would also comment that this tyre is probably dangerous. Regards Peter
BMW Tyre Wear - Richard Turpin
Agree. Duff tyre. Not car.
BMW Tyre Wear - simmo
Paul,
Bulges on the tread face are ususally caused by a separatation the belts. This creates a bulge which wears quickly in an isolated area, often the size of your hand. If you have this get a new one, It is at risk of fairly rapid deflation when you least want it.
a single worn patch cab be due to several other things.
Excessive skidding. This can be a surprise if a previous owner has caused it, as unless you really check the tyres well or it is vibrating the steering wheel, it tends not to show up until much later when the TWI's tread wear indicators are reached, and the tread is low.
Or tyres can be covered in Oil or brake fluid. This causes the affect area to perish and therefore rapid wear in that area. this tends to affect the entire circumference edge, as normally petrol or oil leaks in the boot where the spare is stored flat.

Incidently, remember that if you have any form of wear damage to a tread face, it will tend not to be noticed until the officer/MOT points it out.
If you have just had the tracking done, it may already have been too late to correct the damage.
Cheers Simmo