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whoa
04-29-2005, 12:23 PM
I noticed my rear tire has more wear on the left than the right. Thinking it was an alignment issue I checked at the shop. They suggest the left wear is from road crown. Accepting that crown does have some effect on uneven wear, it still seems the difference should be minimal. In my case, the difference is noticeable.

So what’s the verdict here? Can there be enough difference with wear to notice, or is this more likely an alignment issue? I bought the bike used so there may have been an alignment issue in the past which was corrected.

I did try some hands off to see how it tracks and the bike stays true although I’m not sure how much I would observe even if mis-aligned. The alignment gauge was removed after a lowside drop so all I can do is measure rim to swingarm on both sides, betting of course the wheel is not dished. And I read elsewhere to take two straight edges to run against the front tire but that seems to have a high potential for error.

kurt
04-29-2005, 12:49 PM
Use a straight-edge and check the alignment with the front wheel. I have an 8ft aluminum rip fence I use. Hold it firm against the rear wheel and measure perpendicularly to the front rotor. Go to the other side and repeat. This has worked very well for me. With the bike up on the center stand check side to side play on the swingarm to find out if your bearings or swingarm need replacing/torquing.

bushwhacker
04-29-2005, 01:16 PM
I've heard that road crown crap before and I do not believe a word of it. Personally I think some mechanic made it up to cover his inadequacies in balancing and mounting tires and all the other worthless ones took it up as a mantra.

Which way do you corner hardest. I would think that would have way more affect of the tire wear than road crown.

This is a good article on countersteering but I think it offers some insight on uneven motorcycle tire wear.

Of particular interest is the section regarding the fact that different parts of the tire patch are moving at different speeds thereby scrubbing a portion of the tire whenever you are in a turn. The harder you corner the more the scrub.

http://www.msgroup.org/TIP048.html

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FirstMan
04-29-2005, 01:29 PM
Because I have been to the motorsport ranch 3 times in the past 2 months, the left side is very worn compared to the right.

But, in your case, do you corner harder to the left? Also, on longer rides to you adjust your weight to the right? You would lean left to compensate while going straight.

The first tire on the Valk was worn on the left (bought the bike used), but I haven't seen any issues since. It is on its 3rd tire now.

10-95
04-29-2005, 02:23 PM
My rear tire looks the same. I've been told the road crown does it and if you do a lot of highway miles it makes sense..........

bushwhacker
04-29-2005, 02:30 PM
My rear tire looks the same. I've been told the road crown does it and if you do a lot of highway miles it makes sense..........

When I do a lot of highway miles it wears a flat spot right around the middle of mine with very little tire wear on the tread wall.

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whoa
04-30-2005, 08:29 AM
Maybe the wear has to do with the roads. Much of my riding has been on back county roads rather than major highways and the crown is much more pronounced. The potential for a bad alignment is there since the scale is shot but I'll do what Kurt suggests.

Checking the swingarm is something I had not considered so will get on that this weekend as well.

Thanks for the replies.

Cruzintexas
05-04-2005, 08:27 PM
road crown!!!!! go out and lay in the center of the right lane on almost any FM road and you will see.
Steve

Tx Rider
05-04-2005, 09:34 PM
We also ride in the right lane, making left turns on the outside and right turns on the inside. Along with crown etc. tires do wear differently on either side.

Usually more noticeable on fron tire though.

bushwhacker
05-04-2005, 11:36 PM
If it was road crown the front and rear tires would show the same kind of tire wear.

When you go into a turn you push right to go right. The harder you push right the tighter you turn.

That puts stresses on the front tire that do not exist on the rear. The front tire is scrubbing all the way around the curve and that is waht causes the front tire to cup, not road crown!!!