I have a square tapered BB that needs replacing it is a BB-UN40 110mm.

I have seen that CRC have either a UN26 or a UN54 but not a UN40. Does the number just denote the ‘bling-ness’ of the BB?

Any help would be appreciated.

There is also a 73 on the casing, which I assume to be the diameter of the casing.

73(mm) should be the BB width, as 68(mm) is the alternative

and yes I believe the bigger the number the better the quality in this case.
Shimano dropped a number of models a few years back. as HT II became more previlent.

as above but 110 is the axle length in mm as well.

I’ve got one indoors brand new I think it’s a 73/110 you can have it for postage – UN52 it is.

It’s not really the blingness, it’s more a reflection of the quality of the unit (bigger the number the better quality. Whether it lasts longer is always open to debate.)

73 will be the width of the bb shell the bottom bracket came out off. 110 (or 113 or whatever) will signify the length of the bb axle – always try to replace like with like unless you’re fiddling with chainline.

Thanks for the info.

Joolsburger, if you could let me know that would be great, and what you are expecting for it.

e: stuart at me4pm co uk

Thanks

I’ll check tonight I’m sure its a 73 110 – 2 quid to post I reckon.

The BB I have is a brand new 110 /73 so just what you need. £2.00 to cancer research and I’ll stick it in the post.

J

I have sent an email to your hotmail account as listed in your profile.

many thanks.

Stuart

@joolsburger

You champion!

Should have arrived, let me know.
J