Strange tire wear: What's the problem here?

[RAW]

So, I noticed some odd wear on my front tire the other day.
I took a photo (that doesn't really show the problem, but . . . )

The circled spots are worn more than the rest of the tread; they're low spots.

Is this because of overinflation? or underinflation? or bad balance?

[Cauldron]

Feathering. You need an alignment.

[RAW]

So, you think the forktubes are slightly off in the clamps?

What are the torque values for the clamp bolts?

I figure I can try loosening them to see if that "relieves" any tension. And then just tighten the clamps back up.

Any other suggestions?

[Poolside]

That's classic tire design right there. It's the 90° corner of a tread block that faces opposite the direction of friction. You know, the corner of the square is facing the friction of the road surface. The result is things like braking forces cause the 90° corners to go away first.

The tread blocks are shaped and oriented that way to visually wear out quicker. The tire doesn't actually get less traction with the front corner of the tread blocks worn off, but it sure looks like it does.

And if it looks like it gets less traction, then you need to buy a new tire fool.

Just keep your head down and row, you backbone of the economy

- Jim

[Cauldron]

Originally Posted by RAW

So, you think the forktubes are slightly off in the clamps?

What are the torque values for the clamp bolts?

I figure I can try loosening them to see if that "relieves" any tension. And then just tighten the clamps back up.

Any other suggestions?

don't know the torque. Might help.

You could try the string trick to make sure the back tire is in line with the front.

Or Poolside could be on to something and they all do that. :shrug

[Motornoggin]

Pretty classic block tread wear pattern. I'de say run it until the bars show and throw a new one on.

[RAW]

Thanks. I'll stop worrying about it.


I just hadn't noticed it wearing like this previously.
Maybe I was just too sensitive this week.

[TUCKERS]

Looks like a cupped Metzler Tourance. I'd run 40psi on the next one and keep my eye on it AND the pressure.

[Jeffro115]

Originally Posted by Cauldron

Feathering. You need an alignment.

Aw, don't tease the man.







Raw, my tires do the exact same thing. No problems--all normal wear.


Some fronts do it more than others I have found.

[gsweave]

Originally Posted by RAW

So, I noticed some odd wear on my front tire the other day.
I took a photo (that doesn't really show the problem, but . . . )

The circled spots are worn more than the rest of the tread; they're low spots.

Is this because of overinflation? or underinflation? or bad balance?

Looks like normal BMW R bike tire cupping at 8,000 miles.

I wouldn't worry much about it, though it can be frustrating, I have seen it on about 10 differant tire sets, of mine.

Start looking at other R bikes, you wll see it more often than not.

Combination of Telelever and block tread. IMHO

What PSI's have you been running? How many miles on tire?

If you can squeeze 14,000 miles out of a front, on a GS, you done good

[GSman of La Mancha]

Okay, this thread is old - but - I did a search for cupping and this is what came back...

I have a question related to recent experience. First, a cigar and port wine and some background info is necessary.

Bike is 05 r12GS. Tires are Metz Tourance. I am 6'6" 300lbs ("my Gawd man that's over 20 stone!" he said in awe. By, a bit I'd say was my laconic reply)

On this set, before EVERY STINKING RIDE, i checked and adjusted my air pressure.

I have an excellent, high quality air guage ("it's German and it's expensive therefore it's gotta be good")and I used it to set the pressure at 36 front 42 rear. If my pressure was within less than a pound of these numbers I didn't add air. Sometimes I had to let some air out...

Over the last 6500 miles I have seen NO CUPPING on the front. The prior set which were Trailwings had a cupped front at 6k.

I have had other sets of Metz T's on another GS but I have NEVER been so dilligent about checking AP. These other Metz tires did cup.

Question: Does airpressure - as in over or underinflated tires - lead to cupping? Have I proved anything with this bike re airpressure and cupping being related? After all, the trail wings did cup on this bike where as these Metz T's didn't and nothing has been changed/aligned on the forks etc...

Just curious so I thought I'd "ax d quastein"

[Boatman]

Under inflation will cup the front so will heavy use of the front brake. Put the together and you get severe cupping. Once it starts it's pretty hard to stop.

[ibafran]

Originally Posted by Jeffro115

Aw, don't tease the man.

Raw, my tires do the exact same thing. No problems--all normal wear.

Some fronts do it more than others I have found.

some riders hate the condition and dismount the tire every 1000 miles and flip it over. i think that is a little too anal. usually, to a man, they swear that it works and is the only answer.

[openboatt]

To get that kind of milage out of a tire... obt

[RedRupert]

That sort of tyre wear comes from braking... too much hard braking. So stop braking for corners/turns and look further ahead so as to avoid heavy breaking for other reasons. I'm not saying ride slower!