Originally Posted by
BlueRaleigh
OK, I've got a weird problem. I've been working with Sheldon's instructions and I've got the alignment pretty much near perfect, as far as I can tell, by using the string method. But for some reason, the rear wheel sits ever so slightly further back in the right dropout than it does in the left. This causes the rear wheel to sit at slight angle. Now, I can line up the rear wheel straight and tighten it on, but one side of it won't be pushed all the way down in the dropout. I can't figure out why one dropout seems to be further back than the other.
Odds are it was always that way, since nothing you did lengthened either chainstay. Make sure the wheel is centered between the chain and seat stays because that's what counts. If you have nutted wheels and tightening one side tends to move the wheel over in the other dropout, it's because the dropouts aren't parallel.
You can correct them with a special pair of costly tools, or with a big adjustable wrench (big enough to support most of the upper part of the dropout) using your wheel as a gauge.
Center the wheel, and note it's position in each dropout tighten one side and if the opposite end moves the dropout is off. Remove the wheel and tweak, and repeat. Keep doing this until you dial it in. Repeat the process with the other dropout. Doing it without the tools is much slower, but the tools aren't cheap.
BTW- If the wheel won't simultaneously center between the chain and seatstays (and the wheel is correctly dished) the alignment problem is more complex and you need to do a more complete analysis before tackling that, though you should still go ahead and square up the dropouts..