So I order one of those Rose bikes cheap XTR external BB”s. Its done only 3 months / 1000k use.

Last week it was literally crunching at every turning of the pedals, the harder I pushed, the worse the noise/feeling through the pedals, making the same noise at the same position of the cranks. So I thinks its a duff one, order a replacement £12 XT from Rose.

Today, its all a bit stiff and I have to free it by rotating the cranks backwards. However, once I did that, and throughout the following ride (i didnt bother changing it), its as smooth as silk, no noise or crunching feeling (in fact nothing to feel whatsoever) through the cranks.

Whats going on eh?

It’s objecting to being attached to an Apollo.

🙂

Grrr – whose that *squints at computer*? 😀

Bump – any advice? I’d like to understand the issue if I can, becuase if it isnt dead, there’s probably some maintenance I can do…?

take the crank arms off and take the BB out the frame, then try each bearing separatly by hand – if either of them feels at all ‘rough’ it’s probably on its way out.

not much you can do with shimano BB’s really unless you want to go down the BETD/etc replace the bearings route.

localhero94 has a point…

I presume the BB shell is faced properly? If not, cack can get caught between crank & BB & will be worse at a particular point in the rotation and even stiffen slightly at that point. It does sound like it was a bit of grit or something, especially if it’s cured itself now.

It is faced, and whenever I install I BB I clean the whole inside/outside area pretty thouroughly.

It was a pretty obvious and “big” point of roughness though, and I guess I’m expecting the BB to last longer.

I guess the test will come tomorrow morning – it’ll have seized/be stiff again after not being ridden for a couple of days or ok.

have you taken the cranks out?

It is normally just grit between the arms and the BB covers. The longer you leave it the higher the risk of the dirt forcing it’s way in and also damaging the o-rings on the arms which help keep mud and water out.

I thought my BB was goosed during a mucky ride. Took out cranks when I got back, cleaned all the crap off and put back and now silky smooth

Good point Andy, I shall do so and have a clean up in the morning.

Get a tooth pick and have a good scrape around between the plastic bearing cover and the main bearing cup.Just make sure you don’t push it further in 😀