Swingarm alignment?

[Shainman]

Hey y'all,

My rear wheel has become off center.

I think it has progressively moved over several weeks. First I noticed, after riding, the "dirty" (the area that touches the road) part of the tire was slightly off center to the left. I thought it may be due to that last turn into the driveway. My tire alignment seemed ok. The measurements from the center of the pivot arm to the center of the axle were the same. The bike rode fine; nice and straight, no pulling.

Today I noticed that the tire had scrubbed against the upper inside fender (there's a bit of tube framing up there). I think only when the shocks are compressed after a bump, but I can't be sure.

Today I removed and replaced the rear tire looking for something to account for this problem. All the parts are assembled in the proper order.

Is this an issue with the shocks? Can the swingarm be adjusted into alignment?

Here are some pictures from after today's reassembly.

[Shainman]

Well, it ain't the swing arm and ain't the shocks.
I broke it down today and there is no lateral movement in the swing arm. When I put it back together I tightened the left side of the fender first. I think it may have pulled the fender that way a bit and maybe made it look a fraction of an inch better. The distance from the center of the swing arm pivot to center of the rear wheel axle is the same on both sides. Does that mean the sprockets must be aligned? The chain still sounds little "clicky".
What i think it needs is spacers of slightly different sizes; slightly larger on the sprocket side and slightly smaller on the right side. Anybody know if such items exist?

[Shainman]

*big shrug*

Tore it down and put together again. I can't find anything blatantly wrong. Maybe the frame is twisted and I never noticed. I did buy from a guy who built rat rods. Maybe he "fixed" it up a little before selling.

I scanned around this forum looking for photos of other bikes with this ailment (offset rear wheel). I saw a few.

Anyway, I raised the shocks so at least the tire won't scrub.

[Shainman]

Do these look off to you? (Edit: these pics are from the jack stand thread)

[Vegas Street Rider]

The wheel does look like it is too far to the left. When you tore it down, did you check it against the parts manual breakdown on page 51? There are a few spacers that would have to go on both sides of the wheel. Maybe one is missing or swapped to the wrong side. Hard to tell from the pics.

[Shainman]

Thank you for your response.

Yeah, I tore it down to the swing arm three times I and don't have a single part left over.

I suspected maybe the pivot arm had a bad bushing or something. I can't find anything "wrong".

It's got me baffled. I've got the tire marked up with a tire crayon and I'll get to ride later. If the crayon gets rubbed off, then more head scratching.

Here's some more pics:

[derbydave]

The two bolts on the back arms of the swing arm are used to adjust wheel alignment in the swing arm. The chain should run true between the two sprockets when it is adjusted correctly. Also have the spokes been messed with? You can move a wheel relative to it's hub by adjusting the spokes but be aware if you don't know what you are doing you an also get the wheel seriously out of true.

[Shainman]

Thanks derbydave.

The spokes seem in good condition; they all sound alike when tapped. When it comes to adjusting spokes and truing rims, I definitely don't know what I'm doing. So... no.

I've ordered a chain alignment tool. It should help me understand what's going on. In the meantime, I'll attempt to check alignment with some string.

I think my wheels are parallel but not aligned.

But maybe I think too much.

[Donald McPherson]

A long straight edge from wheelto wheel should help. But remember the front wheel is thinner so make adjustments for that. And remember to teke the measurments from the rim not the tyre.

[Shainman]

Thanks for the tip.

I'll post my findings.