BB For fixed gear build.

[B_A_Brackers]

Hi. I'm fairly new to biking but enjoy building. I'm attempting to build my first fixes gear bike but am having problems understanding which size bottom bracket I need to get. I don't know the frame make or model but do know it's English thread. That's about all. Anyone give me a helpful insight?

 

[RecordAceFromNew]

To select the right bb for your frame you also need to know the frame's bb shell width. It is either 73mm or more likely 68mm.

To select the right bb to deliver the correct chainline (which is important for fixed) you need to know the chainset spec, which determines what bb spindle spec delivers what chainline. You should also have a good idea of what the rear chainline is going to be, which in turn is dependent on your setup at the rear hub.

 

[raleighnut]

^^^^^ +1 BTW

 

[jazzkat]

^ good explanation.