wheel spacing

[57sonny57]

I have a 1980 cb750 with spoke wheels and looking at the back wheel it looks like the wheel is sitting much closer to the right side of the swinging arm than the chain/left side, if you were to put a line in the center of the frame at the rear and plumb down to the tire it looks like it's almost an inch to the brake/right side. Anybody able to help me here??

 

[dirtdigger]

If the chain is lined up then there isn't anything you can do unless you want to have the rim recentered by someone who can true wheels.

 

[57sonny57]

If the chain is lined up then there isn't anything you can do unless you want to have the rim recentered by someone who can true wheels.

My concern also is if the rear wheel is fallowing the front it's going to handle weird if it's not. I guess I should of said that I've yet to ride the bike I've just begun to work on it you have any suggestion on how to check this? And thank you very much for the help!

 

[dirtdigger]

A small amount wont be to noticeable. The original 750's had the front wheel offset from the factory a small amount. the hubs were centered but the rim was laced off center. The only time you will really notice it is on high lean angles in corners.

 

[57sonny57]

 

[dirtdigger]

Have you changed any parts from stock? wheel, swingarm, etc? Could the swingarm be bent or did you do some welding on it that may have warped it? it looks kind of funky up by the pivot area. Are you using stock wheel spacers....it looks like a lot of spacer on the left side. It may just be the picture but the chain looks kind of kinked sideways like the chain alignment is off also.

 

[57sonny57]

Yea it looks that way because of pic but the chain is running straight, as far as I can tell by sight, and there doesn't appear to be any welds other than stock. You don't happen to know what the stock spacer sizes are by chance?

 

[dirtdigger]

I have a 79 parts bike out in the shed. I am going to run out and take some measurements and pictures. Something doesn't look right on the pivot end of your swingarm.

 

[57sonny57]

Sorry man I think what your seeing is the top of a chrome tail light that was mounted under there

 

[dirtdigger]

Maybe the swingarm is just the angle of the picture. Anyway...left picture the hub is about .4" off the swingarm. right side the spacers is 1.4" thick.

 

[57sonny57]

 

[57sonny57]

My right rear spacer looks to be 1"

 

[dirtdigger]

Wondering if someone made there own spacers somewhere along the line because the way mine is setup the wheel looks dead center. I would say look at having some spacers made or maybe look on ebay for some stock spacers.

 

[57sonny57]

Holy shit! I think I might have figured something out here, I think this guy has the damn spacers flipped the wrong way. LMAO if this is what's wrong can't believe I didn't check this. I've even had the wheel off.

 

[dirtdigger]

Sounds like a good place to start. Pull it apart and see if they will swap.

 

[57sonny57]

One last thing to bother you about. This thing has a 49t rear sprocket and I'm in high gear at 55mph what is a good rear sprocket to run? I know that's a difficult question since I don't know what the front sprocket is but if I dropped to like a 42t would I notice a big difference? I want to be able to cruise at a low rpm. Or should I go to a 40t?

 

[dirtdigger]

Whats your engine rpm at your cruising speed? I gear to half of redline at 75mph. You dont want your cruising rpm too low, they are made to cruise at half redline...that is where the power band starts. 42T is a huge drop from 49T.

 

[rtccp]

Hey 57, if you end up going to a new sprocket,I highly recommend getting it from pmp sprocket,phone them and talk to Kim, she is awesome, I am almost done my project ( I put a Ducati single sided swingarm and triumph sport front end on my bike) and I got SCREWED around by Sidewinder Sprockets ( don't use them you will regret it) and Kim saved my ass big time.....nick

 

[vzhang85]

So did you find a resolution to your rear wheel issue? I have a k5 and have a similar issue. Only difference is someone in the past put a 17in rear wheel on it from a hondamatic. My rear tire is hitting my brake stay right now.