BB30 to Hollowtech Conversion

louismichaels

I'm converting the bottom bracket of my Cannondale Synapse (2006 model) from BB30 to the 'standard' to allow me to use a Shimano triple chainset. I don't need advice (or abuse!) regarding the pros and cons of using a triple but would like to know if it is better to use adpator cups that utilize the BB30 bearings in situ (such as made by Wheels Mfg) or to get rid of the BB30 bearings completely, insert the specific alloy sleeve into the bottom bracket which then allows me to use standard Shimano external bearings.

My feeling is to go for the former, and if it's lousy, then go for the latter (which is a great deal easier than the other way round.

Monty Dog

There's also the KCNC BB30 adaptor which is effectively a pair of press-fit housings and bearings for HT2 cranks - I've no experience of any of the solutions. My only notion is that fewer interfaces means less tolerance build up / chance of misalignment

pneumatic

Not an expert by any means (have you tried asking in Workshop?) but I decided not to do this when I upgraded the chainset on my tourer because the advice seemed to be that you should regrind the frame at each end of the BB housing to ensure that the hollowtech external bearing cups were a tight fit.

Seemed like too much faff to me so I sourced some old-style cranks instead.