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Discussion Starter #1 (Edited)
Does your bike want to turn or lean, if you let go of the handlebars? You may need to align the swing arm.

My bike would always want to turn to the left, when I let go of the handlebars. I checked everything, air/oil in the forks and rear shocks, air in the tires, front brake disc's, I thought maybe the frame was tweaked.

Then in my Kawasaki Service Manual (page 230-231) of the download version that shows how to align the swing arm.
I dug around and found a scrap piece of metal that was 2.5mm thick and made U shaped shim. I went through the procedure. My swing arm was off, not much mind you, maybe .5mm. Locked it down at the proper clearance. What a difference, the bike tracks strait now.
You wouldn't think being off that little bit would make the bike act the way it did. All seams well now.
 

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Now I need to go check mine, Thanks!!
 

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Thanks for the info Glenn! When I reinstalled the rear end after I refinished the swingarm, I went out and picked up a couple of 2.5mm valve shims like the manual suggested, and went through the whole alignment process. I am very happy to hear that it was time well spent!! I'm glad you got her running straight!
 

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Oh Man, you are such a Stud!! I have been looking for the cause of EXACTLY those symptoms for a year and that's the one thing I haven't tried.

Any idea what caused yours to start tracking off-center? I dropped mine on the right side very gently (if that's possible) in a low-side slideout and it started pulling to the left.

I will check my alignment this weekend.
 

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Discussion Starter #6
I know my bike was dropped on the right side, before I bought it. No big crash or slide, just layed over. So I don't know if that did it or it was just not done right at the factory or maybe someone greased the swing arm and just threw the adjusters back in. I don't know.
 

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When you say it turned left when you let go of the handlebars, did it require that you constantly push forward on the right handgrip to keep it tracking straight?

Which direction was your swingarm pivot 0.5mm out? Too much clearance between the frame gusset and the swingarm or too little?
 

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Discussion Starter #8
When you say it turned left when you let go of the handlebars, did it require that you constantly push forward on the right handgrip to keep it tracking straight?

Which direction was your swingarm pivot 0.5mm out? Too much clearance between the frame gusset and the swingarm or too little?
Push on the right handle bar or pull on the left, which ever to keep it strait. When you let go of both, the bike would turn left and I mean left. I could not keep it going strait by leaning, if you plopped your right ham off the seat and throw most of your weight to the right side, maybe.
The gap was too wide.
I'm not sure it was exactly .5mm maybe a little more but it wasn't much at all.
I did notice, this syndrome changed, depending on whether you were accelerating or decelerating. Must have something to do with the torque of the driveshaft/rearend.
 

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Damn, that is EXACTLY how my bike reacts - including the change in pull on accel and decel and barely being able to counteract the pull by leaning heavily to the right.

I did a quickie check of the left side spacing of my swingarm yesterday and it is definately over 3 mm. I'm off of work tomorrow and will make the adjustment and test the tracking. I'm pretty hopeful because, like I said above, I've been looking for the cause of this problem for quite a while and nothing else has helped.

Thanks for the great detail in your description.
 

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Discussion Starter #10
Darrel
I tried the eyeball thing at first, adjust a little test ride, adjust test ride, I did this many times. I couldn't get it right.
Then I went around my shop and scrap pile with a digital caliper checking everything. I finally found a hunk of metal 2.5mm thick. 2.5 must be the magic number, because once it was set at that spec, all was well.
My advise would be, find something 2.5mm thick before you start. ChrisC went with a pair of 2.5mm valve shims.
Once you get it set, don't forget to put some RTV on the caps before you push them back on, trust me, they will fall off, if you don't
.
 

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Glenn, thanks for all the great advice. I have been experimenting with aligning the swingarm for about a week and it really made a difference. As you said, the alignment seems to be very subjective and changes with accel and decel, but 2.5 mm from the LH frame grommet seems to be the "magic number." My bike is riding great now.

Edit (3/10/10) - I messed with the swingarm quite a bit back in 2008 and never got rid of the steering pull to the left. Further testing showed that the two wheels are not in the same plane (used a level to shim the centerstand until the rear wheel is vertical, then set front wheel straight forward, parallel with the rear wheel, and checked the level of the front wheel - not vertical!). So, I bought a replacement frame for $100 and last weekend changed it out. It's only a rolling chassis at this point, but the same test shows the front wheel vertical now, so I am hopeful. The real test is when I get back on the road, whether or not the steering still pulls.....

Edit (4/2/10) - Got the bike reassembled this week and rode it for the first time today. The steering pull seems to be corrected! It is now pretty sensitive to weight distribution in the saddlebags as I carry a lot of stuff. It tracked perfectly straight without either saddlebag mounted, but pulls slightly to the left with both mounted, of which the left is by far the heaviest. I think the problem is solved.
 
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