Tire wear

[me&mybmw]

I bought an 02 1150RT used, in the "box o stuff" that came with it was a Michelin front tire (with lots of tread depth) that has some unusual wear. The tire is almost flat across the centre, with what looks like some cupping on edges of the flat spot. I have Dunlop's on the bike now, and I'm sure I see the same happening on the front tire now. Is this a tire pressure issue? The "new" tire has about 6000kms. I have pics, don't know how to post them. can email them.

[R1150Rclean]

I bought an 02 1150RT used, in the "box o stuff" that came with it was a Michelin front tire (with lots of tread depth) that has some unusual wear. The tire is almost flat across the centre, with what looks like some cupping on edges of the flat spot. I have Dunlop's on the bike now, and I'm sure I see the same happening on the front tire now. Is this a tire pressure issue? The "new" tire has about 6000kms. I have pics, don't know how to post them. can email them.

The Mich. MacAdams cupped easily, the Mich. PR1 that replaced it has not cupped at all after 6 k miles when kept at ~40 psi (most of the time) and while avoiding applying the front brake in turns.

[me&mybmw]

Would 40psi in front tire be a good idea for the RT? I'm a tender 180lbs and do mostly solo riding. I have been running 32 -34 as the manual states,I'll bump it up and keep a watch. With ABS, all braking is pretty much synchronized.

[Jed]

I ran the BMW recommended tire pressures on my original set of Metzeler Z6's - the front cupped badly starting at 6K miles and the rear went square by the same time. I replaced both at 8K miles - same brand and model.

I ran the new tires with tire pressures as per a local BMW master mechanic: 39-40 front, 42 rear (about 10% over BMW pressures). 6K into the new tires and not a hint of wear never mind any cupping. Handling has been lighter and quicker, no need to counter-steer to stay in a lean. I have little doubt that I'll get 12K+ miles out of this set. I'm sold on higher tire pressures.

I'll assume that I give up some tire adhesion / traction with higher pressures - but I don't ride hard enough to notice any loss of grip. YMMV

Cheers,

[gregor]

My front Bridgestone BT021 is badly cupped on the sides rather than wearing out the centre as per usual. Ran the tyre at 36psi and will use a few psi higher next time.

[spoon]

With a Rockster, 40 psi front and rear solo. With bags and stuff on, the rear gets bumped to 42 psi. This is with Z6's. I must push the curves because the front wears as fast as the rear. 8000 to 9000 mi. in the hot southwest.

[me&mybmw]

I'm sure now that I have been running to low of a tire pressure. That will change, I'm going to run 40 in both. That is as soon as the snow goes, today it is trying to snow again.....