sq225917-nice tip!

I think early EXBB were pretty badly sealed, newer ones are better, certainly mine have survived a pretty shitty Chilterns’ winter without seizing. But essentially I think for really extended longevity, you’re right to stick to Sqr taper

HTP404, there’s a 50g weight saving, from XT M750 – M770 which, IME also brings better bearing life. I know a lot of people find the opposite, but I trashed Octalink b/bs much more quickly. Seems to be related to weight too, heavy riders seem to fair worse, I’m only 69kg, which seems to help.

At the end of the day, it’s not going away, if you don’t wanna buy it, don’t. I’ve now got a BB30 chainset, and the bearing life is dire. But I’ve got a big pile of warranty ones to keep me going for a while!

Other people’s criteria may differ though.(road)Sprinter friends of mine could snap Sqr taper axles, and I seen a few break on heavy landings.

Tom Boonen was using sqr taper cranks up until recently – can’t recall him snapping any – maybe your freinds should give quick step a call!

However i’ve seen sqr taper axles break on landings on mtb bikes (only un72 thou)

I think each style BB had it’s own advantages and disadvantages.

I quite discount the stiffnes thing for normal XC riding, as you are mostly spinning – and i dare say most decent track cyclists could put down at least 30% more power than most guys on this wesite and efficiency is paramount sucsess in track, and as flexability would reduce effeciency they would be the first to bin them.

Octalink – i always found them very good – it removed the problems of sqr taper (damaging cranks on landings) with very good durability – but slightly less than sqr taper due to smaller bearings.

ISIS – Filth.

External – good idea dogged by poor execution – especially by race face and FSA (my external road FSA BB disintegrated compleatly on a ride the other day) Shimano seem to have the best seals although i’ve yet to try hope etc.

My conclusion is that sqr taper offers good cheap long life option for those not doing anything to hucky. Octalink similar but can handle more abuse by the rider. And external good for heavy folk and those that jump off stuff – just don’t be a knob and jet wash your bike!

The other advantage of external BB’s is that the bearings are cheap & easy to replace.
Certainly cheaper than a new BB

The other advantage of external BB’s is that the bearings are cheap & easy to replace.

That depends how often you replace them 🙂

ISIS – Filth

There are some good uns as well as the bad – FSA seem to last me fine, and SKF are awesome quality.

HTII have been rubbish in my experience – one lasted 3 rides!

Certainly cheaper than a new BB

cheaper than £5.50 ?

and as flexability would reduce effeciency they would be the first to bin them

evidence please. Even if the cranks DID flex, this would not absorb energy in elastic bending, so it’s not obvious that it would affect efficiency

cheaper than £5.50 ?

Where sells BBs for that price?

Where sells BBs for that price?

Secondhand.

Where sells BBs for that price?

UN26 from Parker International

7.15 plus 3.95 postage. You could easily get a decent set of bearings for a tenner 😀

7.15 plus 3.95 postage.

I can’t find them on that site any longer, but there was no postage charge.