Bicycle Mechanics - bottom bracket size

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leilin
09-26-04, 03:22 PM
Hi every one, I need help on the selection of bottom bracket size. My bike is a close to department bike, Mongoose Crossway 2001, from Academy. The bottem bracket is open cup and cone and I want to change it to sealed one. My crank set is Shimano Tourney. I have totally disembled the BB and measured the length of the spindle as 125 mm. Thanks.

leilin

sydney
09-26-04, 04:13 PM
Hi every one, I need help on the selection of bottom bracket size. My bike is a close to department bike, Mongoose Crossway 2001, from Academy. The bottem bracket is open cup and cone and I want to change it to sealed one. My crank set is Shimano Tourney. I have totally disembled the BB and measured the length of the spindle as 125 mm. Thanks.

leilinSo, find a shimano english thread cartridge with a 125 spindle length.
leilin
09-26-04, 04:32 PM
I forgot to mention that the shell width is 68mm

leilin
09-26-04, 04:33 PM
where to find shimano 68x125 BB?
t-blazer
09-26-04, 04:36 PM
a 68 x 122 should work fine .
dafydd
09-26-04, 04:38 PM
You're probably going to have to buy a 68X122.5, to my knowledge shimano doesn't make a 125. get a UN series, the others are garbage. you should be able to find at your LBS or online.

or why not just clean what you have, put in new bearings and roll with it?
leilin
09-26-04, 06:04 PM
have found one that is 68x127, Shimano, LX, 68x127, BB-UN53, 3 pc, Sqr, ENG, BB Set
http://www.bikepartsusa.com/product_info.phtml?p=01-98366

will this work? what about the chain line and the front derailleur? I had before changed my crank set to a better one but the front derailleur could not shift the chain to the largest chain ring so I had to give it up.
dafydd
09-26-04, 06:32 PM
If you measured your old spindle correctly, there is most likely only a 1 mm difference in width. Might work, might not... depends if your old BB spindle is symmetrical or not, how much swing your front der has. kind of comes back to overhauling the old one, unless it's shot.
Gravityhatesme
09-28-04, 02:53 PM
the worst that will happen with the larger BB is you will need to adjust your derailer.