Bicycle Mechanics - bottom bracket question

Hi, i just bought a used Race Face Next LP Crankset on Ebay a couple of days ago, and the seller told me to get a 113mm bottom bracket to go with the crankset. I then bought a 113mm bb from JensonUSA. When i finally got my bottom bracket in mail today i found out they had ship me the wrong bb. (from a Shimano un53 to un73) It is a a better model :eek: , but it is only a 110mm bb. Would that be a big problem for my crankset? or should i just put it in anyway because it is only a 3mm difference. thank you very much in advance for anyone's help. :(

The 110/113 measurement is the spindle length. The spindle length depends not only on the crank, but on the fram you have. The 110 length will sit your crank 1.5mm closer to your frame than the 113. If the crank can handle this without rubbing the frame, then the next thing you need to worry about is if the change will throw your chainline off. Having your cranks 1.5 mm closer to the frame may cause some problems with the way the bike shifts. I know 1.5mm doesn't sound like a lot, but if you know you need a 113, I would use a 113 not a 110. My only question is how your e-bayer knew that you needed the 113.

Because the seller sold him the crankset...

Have you gotten the crankset yet? From the pictures i've seen, it looks like it needs an ISIS bottom bracket. If that is the case, you won't be able to use the shimano. I think 113 is the standard size for ISIS.

Yup, I'd guess that the crankset takes an ISIS bottom bracket, for which the only available spindle lengths are 108, 113 and 118mm. Sounds like you got a square-taper BB.

If indeed your crank takes a square-taper, Shimano's 113mm bottom bracket spindles are nearly symmetrical (both sides stick out equally far from a 68mm bottom bracket shell) whereas the 110mm is asymmetrical, with the non-drive-side spindle 3mm longer than the drive-side.

The 110/113 measurement is the spindle length. The spindle length depends not only on the crank, but on the fram you have. The 110 length will sit your crank 1.5mm closer to your frame than the 113. If the crank can handle this without rubbing the frame, then the next thing you need to worry about is if the change will throw your chainline off. Having your cranks 1.5 mm closer to the frame may cause some problems with the way the bike shifts. I know 1.5mm doesn't sound like a lot, but if you know you need a 113, I would use a 113 not a 110. My only question is how your e-bayer knew that you needed the 113.

Right now I have a similar problem. I took a crank and bottom bracket from an old Fuji to put on a Nishiki Mixte for a friend. Turns out that when I tried to put on the crank it was already touching the frame on the drive side before I tightened it down. Both are 68mm shell's so I knew that wasn't it. I believe that the spindle is too short (3L on spindle 115mm) on the drive side. So I'm thinking that I have to go to a longer spindle to correct the problem. BTW the crank is a SR Apex using a Sugino BB. Any comments?