sprocket aligment

massdrive

massdrive

New Member
Mocking up my first build. Using a GT2A frame, 66cc china 2 stroke, Worksman 26 x 2.125 wheels with 2.5 in. street tires, and a billet aluminum rear sprocket adaptor. The rear tire barely clears the bicycle chain, and rubs on the engine drive chain. What might be the best way to gain more clearance. Thinner tires? Not!, Shims behind the primary (looks like 1/8" max)? Adjustable engine mounts (they look like crap)? I'm open to suggestions.:-||
 
I used washers to spread the frame. My tires are about 2.3 inches wide and there's plenty of clearance.

edit: now I realize that you are talking about the chain rubbing the tire in that case you may want to slide the adapter a bit more to the left. All else fails you can slightly angle the rear tire to the right but I bet you can solve the issue by moving the hub adapter.
 
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I'm not comfortable with the advice to "angle the rear wheel". That throws off sprocket alignment. Both drive and driven sprockets need to be directly in line with each other. Use a straightedge, lay it against both sprockets and the edges should touch, lay flush, across the width of the sprockets. Angling the wheel negates that.

You can gain a little by spacing the sprocket out from the adapter with washers but don't over do it. 1/4" to 3/8" is about as far as you want to go with that.

Smaller tire maybe?

Tom
 
10-4 Tom. I bet he'll be able to use the adapter to solve his problem.

When I was a noob some local guy who rides motor assisted bicycles told me about the tire angling "solution". To be honest it did work but I never felt satisfied with that as a solution. Moot point now that I'm running the MM adapter setup..
 
Thank you all so much for your good advise. I decided to shim the primary sprocket. After I removed the sprocket to shim it I lost it! After looking for it for two days I ordered a new one. $5 bucks for the sprocket and $7.95 for shipping.
zpt

I started this build last June. I figured it would take about 30 days... I've built motorcycles in less time, and with fare fewer headaches...
 
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