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Looking for any ideas. I've been running Michelin Madcams on my 01 900ssie. 2nd set. I'm now at 14k miles. Front tire is experiencing strange tire wear. The tire tread pattern is wearing little 'wedges' in the squares. Take a look at the pictures and see if you can spot the wear....sorry guys it's hard to put to words.

Anyway, the first set eventually produced this pattern as does the replacement set. I stopped by my local BMW/Kaw dealer...as there is no Duc dealer for miles. They were interested in the problem, but have never seen anything like this before.

Funny thing is the very center of the tred shows no signs of uneven wear.

I check tire pressures regularly and run 2.1 - 2.2 bar in the front.

Under heavy braking I sometimes feel 'studdering/juddering' in the front end. Almost as if the tire is being pounded against the pavement.

-Brad


 
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Re: Uneven Tire Wear...any ideas? (bstevenson8)

what you have here looks like "cupping" of the tread. this very common on tires as they get more miles on them, due to being out of ballance. how many miles on the front tire?
 
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Re: Uneven Tire Wear...any ideas? (mh900e0974)

~5k miles...maybe 6. The shop I asked to check it out claimed they were not cupped, but yet couldn't explain. I'll just have to pick up a new one and have balanced.

-B
 
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Re: Uneven Tire Wear...any ideas? (bstevenson8)

The rubber blocks flex from the cornering and braking loads. This is normal wear as long as the tire hasn't been underinflated.
 
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Re: Uneven Tire Wear...any ideas? (bstevenson8)

Cupping, where the front tires have developed a scalloped wear pattern, and where the front of each tread block is worn deeper than the rear is the result of braking, especially while leaned-over in corners (trail-braking).

It is more common to some tires than others because of the design of the tread pattern. It is experienced more commonly on street bikes because most of the riding is straight up and down with lots of braking. Track tires experience this less, especially with softer race compound tires.

It occurs because a bike can decelerate faster than it can accelerate, so there's much higher braking forces on the front tire. This causes the carcass and the tread blocks to distort and develops the wear pattern you mention. The abnormal wear pattern severity is dictated by the tread blocks size and shape, carcass strength, and tire contour. In general, the smaller the tread blocks, the more likely that cupping will occur.

Other factors like low tire pressure or improper suspension settings (too much rebound and/or compression damping) don’t actually cause the problem, but can make it worse. This is particularly true of tire designs that use a lighter carcass design construction such as the last two generations of Michelin radials. Such designs depend more on the rubber compound/tread area for additional strength.

Tire selection may help. Dunlop 207s, for example, use a heavier carcass and softer rubber construction which helps limit this problem. Pirelli Evos, although they have a lighter carcass, don't usually exhibit this problem because of their larger tread blocks.

To minimize this wear pattern, whatever your choice of tire, maintain proper tire pressure and resist the urge to trail-brake. If you can get through a curve with slight trail-braking, you can likely negotiate it without any trail-braking by concentrating on your cornering technique. Do most of your braking while riding straight up or only slightly leaned. Make sure your suspension is properly adjusted for your weight and properly damped.

On a personal note, after experiencing cupping on a Ducati 916/ Pirelli Dragon combination, I made a deliberate attempt to change my riding technique and do most of my braking BEFORE leaning over into the corners. The result ... almost no cupping.
 
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Re: Uneven Tire Wear...any ideas? (bstevenson8)

I call this the Michelin syndrome, I have had that tread style Michelin before and had them do the same thing to the point that the leading edge of the tread block was flush with the tire carcass. The tire was not out of balance, it was more a function of the tread block size and placement. My Michelin Pilot Powers show no wear after 1k+.
 
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I just plain call it tire wear. I have seen that on all my bikes with many different tire manufactures. My FZR 600 did it with Dunlop's, my GSXR 1100 did it with Dunlop's and Michilen Macadaam's, my 916 did it with Perrelli's, and my 888 did it with the Michelin Hi SPorts it had. I will see how the new Pilot Powers hold up.
 
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Re: (duckboy)

My Hyabusa would do that after 500 miles. Of course that was something like 250 wheelies
 
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Re: Uneven Tire Wear...any ideas? (Shazaam!)

Uh, good stuff on trail braking but my pilot sports were not like this when I put my bike away for the winter and they were when I broke it out of the garage in the spring.

BCM tells me that the pilot sports and others have this tendancy after aging where with styles where the tread grooves criss-cross. The Pilot Powers apparently attempted fixed this with a new tread pattern (tread does not completely criss-cross).
 
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