Looking at HT2 BB’s and wondered if there is actually any difference between a Deore and XTR? Seen this cheap, but wondered if its worth going for a cheaper one. http://www.rosebikes.co.uk/article/shimano-xtr-bottom-bracket-shells-hollowtech-ii-sm-bb90/aid:274227

This gets asked quiet often. I think the consensus is they arent all the same. I know from looking at them that the outer black seals are a different shape between deore, xt (slx are the same) and xtr. Others mentioned that one of them uses a different size or width bearing (deore I think) – when they were trying to replace the bearings with cartridge bearings. While I get on fine with the xt/slx ones that is a cracking price to get some xtr on your bike!

Hope that helps.

Deore is lowest spec.

LX/SLX/XT all seem to be the same.

XTR looks to be the same but black (£3 more at Rose but a lot more at other places).

IME anything other than Hope or CK are made of cheese.

My XTR BB is still going after 3.5 years 🙂

The XTR BB on my HT (that gets used in all weathers) has been going for 2 years and has been swapped between frames. Still running smoothly.

I bought 2 of those Rose XTR BB’s and the pack was delivered within a few days, well worth it.

BETD do a BB HT2 re-furb for £20 with (apparantly) extra special bearings.

Anyone got any experience of that?

I know a bit about this subject.
The cups are deeper on the lower spec ones, XTR and I( think) road ones have narrower bearings. 5mm as opposed to 6mm IIRC.
I made the mistake of buying replacement bearings, found out they dont fit all BB.
Hope that helps.

BETD do a BB HT2 re-furb for £20 with (apparantly) extra special bearings.

Anyone got any experience of that?

Yep – replaced a 2 year old xt one with betd enduro ones. Fitted free and super fast turn around. Lasted 6 weeks before I could feel gritty grinding through the pedals. Back to XT after that.

Im pretty sure ALL Shimano bearings are 6mm rather than the freely available bearings which are 7mm. However you can fit them into your old BB shells.
I got a SS BB and when the bearings died bought some more replacement bearings and put them in.
The bearings are 61805 2RS and are feely available from most bearing websites. Cheap ones wont last as long as more expensive ones. Top tip is to take off the rubber bearing seals before fitting and cram them full of more good quality grease before installation.