bottom bracket facing

Larok

Hi, does a bottom bracket need refacing each time an external bottom bracket is fitted, (hollowtech2). Or just the first time?

nicklouse

just once, unless you have damaged the bb and it is no longer OK.

Larok

Hi, thanks. The BB is OK. I am installing a new M770 XT crank as the rings on my M760 XT are worn and I thought it would be a good time to get into the most recent XT chainset, my thinking being it will be another couple of years until the next revision comes out. Would it be better to keep the old BB and install the new crank through it?

glen4

If your chainrings are shot, then almost certainly the BB will be toast too. Best bet is get it faced and fit a Hope BB, then forget it, as it will last ages. The std. shimano BBs are notoriously badly sealed, and wear out very quickly, had mine apart a couple of times to regrease the failing bearings, but was only putting off the inevitable replacement

ride_whenever

but if you buy the new cranks they'll come with a new shimano one, so bosh those in and run them into the ground before splurging on a hope...

Anonymous

and bear in mind hope bb hasnt been out for all that long iirc so the claims of everlasting bearings might be a bit premature.

switchback18

Like Nick said, once the shell is faced, it doesn't need doing again - facing just puts the face perfectly at 90 degrees to the threads. When this is done it's done. Facing it every time you fit a new BB has no effect except to make the shell narrower & narrower - eventually it'll be too narrow!

glen4

sheepsteeth wrote:

and bear in mind hope bb hasnt been out for all that long iirc so the claims of everlasting bearings might be a bit premature.

Have had mine fitted 5-6 months now, had already stripped the standard one and regreased it after a few months, hope one is still as smooth as a cashmere codpiece

Anonymous

i have had shimano ones and race face ones which have lasted for more than 12 months and they only cost 20 quid to replace depnding on what you replace em with

glen4

sheepsteeth wrote:

i have had shimano ones and race face ones which have lasted for more than 12 months and they only cost 20 quid to replace depnding on what you replace em with

Spose a lot depends on how many miles and in what conditions you ride in

Anonymous

i completely agree. lets us know how you get on with the hope one, would be intersted to see if the price tag equals longer service

glen4

sheepsteeth wrote:

i completely agree. lets us know how you get on with the hope one, would be intersted to see if the price tag equals longer service

I certainly will, and after six months or so (after which the shimano std one was knackered), the signs are good

stumpyjon

Hope BB's do come in many splendid colours, does this justify the extra cost :?:

Anonymous

so do superstar ones but for only 20 quid!!