At 01:50 PM 8/7/04 -0700, r cielec wrote:
>Let's see if I can articulate the question. Rear drop-out can be paralell
>to each other but not necessariyl aligned with "track" of frame.
>So, when checking drop out alignment, how would one first ensure that at
>least one drop-out is in proper "track"?
Assuming that the frame has been built accurately; If both dropouts are equidistant from the centerline of the frame (which I check before aligning dropouts), then getting the faces parallel, with the curves at the ends of the slot concentric, then the plane of the wheel will be the same as the plane of the frame. (Assuming a properly dished wheel.)
However, if the chainstay or seatstay lengths are not exactly equal then "perfect" alignment can only be achieved by adjusting the location of the slot.
On the other hand, maybe "Close Enough" really is close enough. While all framebuilders strive for nearly perfect alignment, there are many tales of bikes that handled OK until a slight misalignment was corrected. Then a shimmy or else a "vagueness" in the handling shows up. Perhaps because small forces applied to the contact patches due to the misalignment had been preloading the clearances bearings need to operate efficiently.
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