Shimano Road vs MTB BSA BB

Posted on Mon 4th, November 2024

• #1

rob_g_clarkson

is there any difference between the two, other than the plastic sleeve doodah?

eg; I have an MTB BB and am about to acquire a road bike frame (68mm BSA)... will i be ok just buy the little plastic sleeve that goes in between the cups??!?

ta
• #2

M_V

Hollowtech 2?

I think there’s meant to be a difference in the width for at least some models. I doubt it’d actually make any difference in reality though.

You don’t really need the plastic sleeve so if you have the bottom bracket and the cranks already then you don’t need to spend anything to try it out.
• #3

rob_g_clarkson

That's a fair point!... will try 👍🏻
• #4

TooTallTim

MTB cups are narrower, so using them in a 68mm shell usually means needing to use some BB spacers. Apparently the bearings are slightly better sealed too
• #5

Kimmo

You can use a couple of those 10s cassette spacers - they're the 1mm each side you need.
• #6

rob_g_clarkson

Great stuff... thanks both

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