Fit a Shimano Hollowtech II (24 mm) crank in a BB30A press fit (Cannondale) shell
Whether a Shimano Hollowtech II (24 mm) crank fits a BB30A press fit (Cannondale) shell, and the bottom bracket that makes it work.
The crank and the shell
| Crank spindle | Shimano Hollowtech II (24 mm) (24 mm constant diameter) |
|---|---|
| Frame shell | BB30A press fit (Cannondale) (42 mm smooth press-fit bore, 73 mm (asymmetric, 5 mm wider on the non-drive side) wide) |
| Verdict | needs a reducer |
| Bottom bracket to buy | BB30A to 24 mm Shimano reducer bottom bracket |
SHELL BB30A press fit (Cannondale) (42 mm smooth press-fit bore, 73 mm (asymmetric, 5 mm wider on the non-drive side) wide)
SPINDLE Shimano Hollowtech II (24 mm) (24 mm constant diameter)
BB BB30A to 24 mm Shimano reducer bottom bracket
SPINDLE Shimano Hollowtech II (24 mm) (24 mm constant diameter)
BB BB30A to 24 mm Shimano reducer bottom bracket
A 24 mm Shimano crank runs in a Cannondale BB30A 42 mm bore using a reducer BB that presses into the 73 mm shell and steps the bearing down to 24 mm.
Use the BB30A-specific reducer, not a plain BB30 one. The shell is 73 mm and asymmetric, so a symmetric BB30 reducer sets the bearing spacing wrong.
The bottom bracket to buy
Search Amazon for BB30A to 24 mm Shimano reducer bottom bracketaffiliate searchFind BB30A to 24 mm Shimano reducer bottom bracket on eBayaffiliate
Related fits
Shimano Hollowtech II (24 mm)24 mm spindleBB30A press fit (Cannondale)42 mm bore, 73 mm asymmetricShimano Hollowtech II (24 mm) in a BSA / English threaded shelldrops inShimano Hollowtech II (24 mm) in a Italian threaded shelldrops inShimano Hollowtech II (24 mm) in a T47 external (T47-68 / T47-73) shelldrops inShimano Hollowtech II (24 mm) in a PF30 press fit shellneeds a reducer
SOURCES: Park Tool, Bottom Bracket Standards and Terminology · Wheels Manufacturing, Crankset Spindle Standards & BB Compatibility · Wheels Manufacturing, Cannondale BB30a & PF30a Bottom Bracket Guide · Kogel Bearings, Cannondale BB30A and PF30A explained