Bicycle Mechanics - Adjustable cups on BOTH sides of loose-ball bottom bracket

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simplify
05-08-06, 05:09 PM
I have an Italian threaded BB shell, so I could use right-hand-threaded adjustable cups/lockrings on both right and left sides of the (traditional 3-piece) bottom bracket. I'd like to do this so I can fine-tune the chain line, and also to be rid of one part that's not easily user-removeable--the fixed cup. Is there any reason NOT to do this?

cascade168
05-08-06, 05:28 PM
I have an Italian threaded BB shell, so I could use right-hand-threaded adjustable cups/lockrings on both right and left sides of the (traditional 3-piece) bottom bracket. I'd like to do this so I can fine-tune the chain line, and also to be rid of one part that's not easily user-removeable--the fixed cup. Is there any reason NOT to do this?

Just thread in one side and lock it down - now that's your fixed side. Then screw in the adjustable side and treat it normally. You may have some minor side-to-side issues. With a regular fixed cup, the side-to-side position of the axle (with respect to the BB tube) is fixed. By using two adjustable cups you now can move the axle from side to side with respect to the BB tube. The fact that you realize you can move the chainline leads me to believe you understand what's going on.