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Old 12-12-13 | 01:05 PM
  #10  
FBinNY
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Joined: Apr 2009
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From: New Rochelle, NY

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Originally Posted by nillevang
If you look at picture #1 the left dropout (the right side when you're riding the bike) is couple of milimeters lower than the other side.
Sadly this doesn't tell you anything specific. The misalignment can be caused by the dropouts being in different places, bot just as likely by their faces not being parallel. When one uses dropout alignment tools (made for the job) the process requires that the ends not only meet in the middle, but that the gap between the cups be uniform all the way around (parallelism). With threaded rods, you can't know what you're looking at.

Frame/fork alignment is a complex thing involving many factors that can combine in various ways. The key is that both wheels be in the same plane and that the center of gravity of the rider is also in the same plane. Both conditions being met ensure that a bicycle will track, but interestingly the bicycle can still track if neither are met, as long as the various errors cancel.

In fork alignment the key is that the steering axis lies within the front wheels plane. This can be met even with a badly twisted fork, and may not be met with a fork where the wheel aligns perfectly between the blades.

The fact that your bike pulls is best evidence of misalignment, but without a series of measuements we can't rule out things like a twisted (off plane) head tube, bent steerer, off position front wheel, and so on...

I wish I could make this as simple as start here, go there, but it's just not that way.

If there's a framebuilder, or good shop in your area, let them do a thorough analysis of the frame and fork's alignment and straighten it properly.
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