Press Fit Bottom Bracket Repair

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 NOISY PRESS FIT BOTTOM BRACKETS

My Cannondale 2010 era BB30 has been noisy for 10 years. I have tried multiple fixes. In the end: Two complete bearing failures and a damaged frame shell. All appear to be related to poor alignment of the bearings that induces movement between at frame shell junction. For BB30, and most press fit BBs, primary interference (i.e., the place where the bearing is supposed to be firmly seated and immovable) is between the bearing and frame. FWIW: Electric motors I have worked on, have the interference between the axle and bearing - with frame friction being lower. This is generally a better design - especially when you want quiet operation. Only Campagnolo Ultra Torque has this axle interference design. Go figure. 


Long story short: My BB30 bearing had too much movement where it mates with the frame. I tried using red Loctite as a permanent fix. That only lasts a few rides. Same for pumping in large amounts of grease.

REPLACEMENT SLEEVE

I purchased a $200 replacement sleeve from BBInfinite. It fixed my damaged BB frame shell. This solution keeps the bearings aligned and properly spaced while preventing movement at the critical bearing-to-shell junction. Installation took about 10 minutes. This repair has been flawless and silent for 6 months. I anticipate no more problems.

SOLUTION FOR AN FSA CRANK IS EXPENSIVE

I have FSA cranks with a 30mm axle. This limits sleeve-based solutions to a small number of standard bearings that fit this large axle and small frame clearance. If you are lucky to have Shimano cranks, you have more options. It has a 24mm axle that allows more bearings to easily fit in a replacement sleeve. These solutions start at under $50.

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