BB91

lef

Anyone familiar with BB91? I'm thinking of getting a new frame with this type of BB. I take it all cranksets that fit bb86 fit BB91? I have a rotor 3d quarq so want to be sure its going to fit. Also are there any reports of creaking?

Did some searching but couldn't really find that much info.

Monty Dog

BB91 is Specialized proprietary version of BB86 and is for a regular 24mm dia spindle eg Hollowtech 2.

lef

How does it compare to other BB types? Is it any good, and bad reports? Cannot find much to suggest there are common problems.

Vinnyc19

Its ok, they don't last that long and are a pain to change if you don't have the right tools

TheRealGuybrush

The BB91 is identical to other Press-Fit BB's however the bearing cups are (as Monty Dog said) a proprietary design with a slightly different ID. They are made for Specialized by Shimano so getting replacements are slightly harder as you'll have to get them from a Specialized dealer.

You will need the right tools to fit them and you can't take them out and put them back in as the cups are only plastic and are damaged (even with the correct tools) when you remove them from the frame. However this isn't just the BB91, this applies to all Press-Fit sizes. The correct tools are a little expensive but a good LBS can do this fairly cheaply.

ricky1980

bloody cons i say! all these pressfit BBs are made out of cheap plastic. if they use alloy or steel they will last a long time guess then they won't make any money on them.

threaded BBs for me...thank your very much