 1 Week Ago | #1 |
 | Bottom bracket length I'm trying to get a bottom bracket for a build i'm putting together and need to get my head around what bb length I should go for. From what I've read the length is set from the crank and should follow what that says. However, I can't see anything more on my crank than the name (Silstar ) and length of the arms (165mm). Is there another way for me to get the measurement I need? Cheers! |
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| 1 Week Ago | #2 |
 | its easy to get bb length. firstly you need to measure the length of the bb shell. and next is to measure the length of the spindle, from end ot end. with those 2 measurements you should be able to find a new bb. Im assuming you are going to purchase a new one of the same size. |
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| 1 Week Ago | #3 |
| | The problem I have is there is no bb currently in the frame otherwise I'd get a like for like replacement. Is there not a way I can calculate what spindle length I need from taking a measurement from the crank, or is there a standard size for single-speed gearing ? I can't seem to find any information that really makes sense to me. |
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| 1 Week Ago | #6 |
 | UTFS! Seriously, there is a wealth of information on here about this. If you know what hub and chainset you're using then the transmission database should give you an idea of what other people are using with that set up. Failing that, get a ruler and measure the frame and rear hub and from that you can calculate the chainline you're going to have. Then buy a bb with the axle length to give you that chainline. The Sheldon Brown page on chainline is also well worth a read. |
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| 1 Week Ago | #7 | |
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But I'm not sure he can work out his BB length. It totally depenends on being able to find out accurate information about the crankset he has, and I certainly can't do that. You'll need to offer it up to some BBs to see if it's shimano/campag taper, then try threading it down on to some to find out how far down the taper they sit and therefor what BB length needs. Jobs for a local bike shop who've got some various BBs lying about | |
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