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Here we go again! Last fall I purchased a used MS with about 12K miles on it. The front tire, in addition to being worn out, had an unusual cupped wear pattern. At that time, I was concerned that this indicated a problem with the bike as it had suffered a fall over in the driveway and had a dented fuel tank, but no other signs of damage.
After inquiring on this forum and talking to the dealer, I concluded it was caused from improper tire inflation pressure by the previous owner. Several people suggested a pressure of 40psi instead of the 36psi reccommended by the book. So I replaced the tire with a Dunlop K510A-120/70R17,the only tire I could find locally that would fit it. In fact, the stock 130/70R17 tire is very hard to find.
Since replacing the tire I have only put about 800 miles on it. The other day, I got to looking at the front tire and discovered a repetitive wear pattern that exaclty coincides with the tire tread pattern! BTW, I've watched the tire pressure like a hawk! It's not severe, but enough to be noticeable.
I talked to the Kawasaki dealer and asked him if he thought there was a problem with my bike. He said he didn't think so, and said he suspects the radial tires. He said they're a lot of problems on bikes. If this is so, I sure wish I had known this before I bought the thing.

Is anyone else having a similar problem on their MS? A friend told me that this particular Dunlop tire was trash. If so, it was one expensive piece of trash. Anyone have any ideas about what's going on?
 

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several riders have had the problem, icluding myself. In fact I had the cupping on both tires. I also increased the psi on both tires to 40 psi tires. I also replaced the OEM front tire with a 120. Both replacements were the orig. Dunlops. So far after about 4000 miles both seem to be wearing evenly. I like the narrower 120 front better than the orig. size. You might try increasing the psi a couple of pounds from 40 to see if it helps.
 

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R.I.P. Deron Harden
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I had the same problem with mine, only got 5000 from the originals. I switched to Metzler Z6s. Stock size 170/60 in rear, with the 120/70 up front. Love 'em so far, but I only have about 300 miles.... will keep you up to date.
 

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I have not seen the problem yet with ~5000 miles on my MS. I am going to keep my eyes open.
 

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R.I.P. Deron Harden
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2500 miles on the Mets Z6's. The front looks brand new, but the rear is starting to cup on the shaft side. I'm running 40lbs in the rear and 38 in the front.
Oh well.... maybe try Avons next time
 

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it is caused by low air pressure by what I have seen and heard, I run 41 in both on my 1600 and not 1 cup in the front tire and I have 10,000 miles on it and it is not yet 1/2 worn out.
 

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I'm wondering what information on tire wear patterns you are using to draw your conclusions. Is there a source you could quote as to how the tires should be wearing?

:smile:
 

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I like vintage stuff!
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You ought to consider checkng your alignment, too. It takes a little bit of time, but very easy to check and you've got the confidence knowing whether your wheels are in alignment of not. I type "motorcycle wheel alignment" in the Google search engine and got lots of how-to's. This one looks easy to understand:

http://www.motorcyclistonline.com/howto/stringalign0402/
 

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here you go, hope this helps.
Cupping, which is more accurately described as scalloping, is a natural wear pattern on motorcycle tires and it will always follow the tread pattern. It is not a sign that you have bad suspension parts. It merely shows that your tire is indeed gripping the road when you make turns (thank you for that Mr. Tire!). This scalloping develops within the side wear bands of a leaned motorcycle. The extreme forces that come in to play when the bike is leaned in a turn are what produce the effect and when the wear becomes sufficient, one will experience vibration and noise when one banks into a turn. scalloping follows the tread pattern. The leading edge of the tread grips the road and the rubber is scuffed off the tire in that area causing a depression. As the tire rotates, the pressure moves to the trailing edge of the tread pattern and the tire flexes there which causes less scuffing so less material is ground off the tire. The more complex the tread pattern, the more complex the scalloping pattern will be. The softer the compound of the tire, the sooner this scalloping will develop. Radial tires are more prone to cupping than are bias ply because the compound of radials is softer. Low tire pressure will exacerbate this wear pattern and you will lose many serviceable miles by running low. Improper balance has nothing to do with "cupping" on a motorcycle tire. Improper balance will merely cause your bike to vibrate within certain specific speed ranges.
 

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Very interesting ... I knew tire pressure played a role. Didn't think about the forces on turning.
 

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Would it be possible for someone to take a picture of this effect so that those of us "imagination challenged" people can see what it looks like? :D
 

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Constrictor said:
Would it be possible for someone to take a picture of this effect so that those of us "imagination challenged" people can see what it looks like? :D
You probably couldn't see it in a picture. If you take your hand and rub it softly around the tread of the tire, you can feel little "ramps" in between the tread patterns, the higher edge will be before a tread groove as you move your hand towards the bike. (brake side, rubbing counter-clockwise; clutch side, rubbing clock-wise) If your hand just glides smoothly and you only feel the grooves, you're good. If your hand wants to bump up slightly before each groove, then your tire is "cupped".

It happens on my R6 front tire every other season, but then again, I'm putting a lot more force on that than I will on the Streak.
 

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I had a similar issue with the set of Dunlop 208's I put on. I watched the tire pressure closely and had it set at 36 which seemed to be the right consensus but at about 4000mi cupping become more noticeable. I cranked it up to about 40psi and for the last 1500 mi the tires actaully seem to be wearing better. I swapped front and back this weekend for Michelin Pilot Road's (caught a screw in the rear tire last weekend and didn't want to trust my fix on longer road trips) 120's up front, a 180 in the rear. I questioned a tech and again he recommended 36 up front, 40 out back. I've heard great things about these tires and they were very reasonable over the net. I was able to purchase both tires, ship and install for less than $300 which I was happy with. Time will tell.
 

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Constrictor said:
Would it be possible for someone to take a picture of this effect so that those of us "imagination challenged" people can see what it looks like? :D
here is a picture with cupping, the tire was ran thru baby powder and the powder sticks to the high spots and not he cupped spots.
 

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the "fun" guy
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1600pilot said:
here is a picture with cupping, the tire was ran thru baby powder and the powder sticks to the high spots and not he cupped spots.
Hmmm...I think I'll put baby powder on my tires for the trip to Red Lodge! LOL :)
 

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whistle clean said:
Hmmm...I think I'll put baby powder on my tires for the trip to Red Lodge! LOL :)
well at least they will be soft and supple then, and smell very nice :mrgreen: :mrgreen: :mrgreen: :mrgreen:
 

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the "fun" guy
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1600pilot said:
well at least they will be soft and supple then, and smell very nice :mrgreen: :mrgreen: :mrgreen: :mrgreen:
As soft as a baby's behind! :)
 
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