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08-06-2004, 09:27 AM

supabonbon wrote:
>>
>>>What is the major difference between track cranks and regular road
>>>cranks when it comes to chainline issues?

I replied, in part:

>>Track cranks generally have about a 42 mm chainline, sometimes a bit
>>less. See: http://sheldonbrown.com/chainline
>>
Jim Smith wrote:
>
> Does it make sense to speak of chainline for a crank alone?
> I had thought that it really only made sense for a BB and crank
> combination. At least for square taper cranks, whose BBs are
> available in so many sizes that one can adapt them to most any
> chainline. Or am I missing something?

My assumption was that the mysterious "supabonbon" was referring to
standard installations, where the manufacturer's recommended bottom
bracket would be used.

Otherwise, the original question would have been meaningless.

Indeed, if you mix and match bottom brackets, you can do all kinds of
non-standard things with chainline.

Sheldon "http://sheldonbrown.com/chainline" Brown
+--------------------------------------------------------+
| As far as the laws of mathematics refer to reality, |
| they are not certain; and as far as they are certain, |
| they do not refer to reality. --Albert Einstein |
+--------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

08-06-2004, 09:27 AM	#17 (permalink)
Sheldon Brown Guest Posts: n/a	Re: Track cranks/bb question supabonbon wrote: >> >>>What is the major difference between track cranks and regular road >>>cranks when it comes to chainline issues? I replied, in part: >>Track cranks generally have about a 42 mm chainline, sometimes a bit >>less. See: http://sheldonbrown.com/chainline >> Jim Smith wrote: > > Does it make sense to speak of chainline for a crank alone? > I had thought that it really only made sense for a BB and crank > combination. At least for square taper cranks, whose BBs are > available in so many sizes that one can adapt them to most any > chainline. Or am I missing something? My assumption was that the mysterious "supabonbon" was referring to standard installations, where the manufacturer's recommended bottom bracket would be used. Otherwise, the original question would have been meaningless. Indeed, if you mix and match bottom brackets, you can do all kinds of non-standard things with chainline. Sheldon "http://sheldonbrown.com/chainline" Brown +--------------------------------------------------------+ \| As far as the laws of mathematics refer to reality, \| \| they are not certain; and as far as they are certain, \| \| they do not refer to reality. --Albert Einstein \| +--------------------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone 617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide http://captainbike.com http://sheldonbrown.com