Re: Fat tires?
A little lateral misalignment will not hurt. I wouldn't go much more than 3/8". Check your sprocket too. Most of them have a 'dished' design whereby the teeth are further to one side than the other. If the teeth on the sprocket are toward the wheel you can reinstall the sprocket with them on the outboard side instead. This won't give you much, maybe 1/4" but that might be enough to give you the tire clearance you need. Make sure your wheel is centered in the frame also and not cocked to the left. You didn't say where the chain is hitting the tire but if it is the lower side, the one with the tensioner, you can get some clearance by moving the tensioner wheel out a bit. Make sure it is running true and you don't have excess chain slack. You want 1/2 to 3/4" slack in the chain measured at the center of the chain span. Hope these suggestions help you out. Good luck.
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