Originally Posted by Ken Cox
I've only had this bike two and a half days, and I haven't played with it, mechanically.
Given the off-center nature of the tire in the seatstays, it has occurred to me I might loosen the axle nuts and see if I have any wiggle room that will center the tire between the seatstays.
This could correct some or all of the problem - but - if it doesn't, do I understand from absntr that a 107mm bottom bracket alone will give me better chain alignment?
Ken - that would be my first adjustment. A wheel not aligned in the dropouts will throw off your chainline. A few things you can do to remedy this (if this is the problem, which it sounds like) is to (as you've guessed) is to loosen up the track nuts re-align the wheel and crank those track nuts down. Due to the high gearing (48x16), the amount of torque you're applying, especially on uneven terrain will lead to rear wheel slippage if the nuts aren't sufficiently tightened. To make alignment and chain tensioning easier, you may want to invest in some chain tensioners. I picked up some MKS tensioners this weekend, small, beautifully made and NJS certified. They look like this:
http://businesscycles.com/trtool_chaintugs.htm
A 107 mm bottom bracket will not solve your problems. I had to get one to mate it with the Sugino 75 crankset I upgraded. Chainline is dependent on a few things: BB, crankset, rear hub. This is a handy reference (though track specific):
http://businesscycles.com/tr-refspec.htm#b/b
This all depends on the thickness of the crankarm and the length of the BB that's needed to either draw it closer or further away from the frame to achieve the proper chainline.
As the poster above noted - the chain engaging the chainring will indeed make noise. If you don't hear it on the street, then you're pretty a-ok.