Bicycle Mechanics - BB Length - how far out of 'spec' is acceptable?

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cuda2k
09-15-05, 04:57 PM
This morning, after laboring for a good part of an hour I successfully replaced the old crankset on my Schwinn Traveler with a NOS Shimano 105 double. The one coming off of it was a double, so in my not so experienced mind, I figured it would work. Well I knew pretty quick that it seemed that the 105 seemed to sit a whole heck of a lot farther out on the spindle than the one coming off. And sure enough, the FD didn't want any part of trying to shift onto the large chain ring.

So off to the wonderful internet I go to find out what I should have started out looking for - what BB spindle length I need. First (and of course only) stop was SheldonBrown.com which states that my crank (if I remember the part number correctly) needs a 107mm length. My primary question is, how much out of spec, ie: longer, can the spindle be before I run into the same problems I encountered this morning. I roughly estimate if I needed a 107, then what is on the bike is about a 113+ or so. Do I really need to source out a 107, or will a 110 work? Thanks!

EDIT:
Adding a bit of info that I forgot to mention and the first replier reminded me to add:
1) yes - square tapper
2) getting my hands on a 107mm seems to be easier said than done. I've only checked a couple of locations thus far online, but only loosescrews.com has a 107 length (that or some over priced ones on ebay). I have one other BB but that's at a buddies place with my other frame. I'll check the length on that and maybe I'll luck out (doubt it though as it went with another older (early 80's) crankset.


Retro Grouch
09-15-05, 05:06 PM
Square taper I assume.

If you're buying a new bottom bracket anyway, I don't understand why you wouldn't want to get the right one. If I already owned a 110mm bottom bracket I'd try it because I'd have nothing to lose but if I were buying one I'd get the 107mm.

cuda2k
09-15-05, 05:13 PM
Square taper I assume.

If you're buying a new bottom bracket anyway, I don't understand why you wouldn't want to get the right one. If I already owned a 110mm bottom bracket I'd try it because I'd have nothing to lose but if I were buying one I'd get the 107mm.

Edited original post to add info per your reply. :)


DannoXYZ
09-16-05, 01:29 AM
The 110mm one should be fine. Toss it in there and see how it works. Have you adjusted the inner & outer limit-screws for the new chainring positions?