Topic: Question on Chain arrangement

[KB02]

So this is a question for the technicians out there:

Is there a specific measurement that regulates the distance that drive chain is placed away from the rear tire? Or is it a matter of just spacing it out away so that the chain isn't touching and it lines up with the drive sprocket?

I think I may have found a solution to the sprocket alignment issue I have with 750K8 project. For those reading this that have not read my build thread, I am placing a 1989 Suzuki Katana rear tire into the CB's swingarm and the sprockets are offset by about 5mm (roughly 3/16"). Cycle-X sells a 10mm offset front sprocket, but that will put the chain twice as far as I need it. I could space out the rear sprocket then to match, but I run out of room against the swing arm. I could mod the swing arm... yada, yada, yada... 

I got to looking over the Suzuki hub last night and I think I can just shave down the hub where the sprocket attaches by about 5mm (the thinnest area where I would be shaving is 10mm thick) and I'll be all set, but that puts the chain about 5mm closer to the tire.

SO - Is that a bad thing?

I mean, obviously I don't want it to rub, and I've got the clearance, but is there a minimum clearance that I have to maintain?

I welcome your thoughts. 

[scondon]

 As far as I know it is just important that the chain is straight from front sprocket to rear. Distance off the rear tire can change depending on which size tire you install. I've seen bikes with rear tires so fat that the chain rubs against it, though I doubt you want that. If you can fab it up so there is at least 1/8" gap between tire and chain then I think you'll be happy. Even down to 1/16" but then there's not much margin for wear and slop.

  Just my thoughts and not intended as a guide

[sohc4]

Yes, getting the front and rear sprocket in line is what is important. If you need more clearance to the tire, you will need to offset both sprockets by the same margin - keeping them in line is crucial.

Cheers,
Axl