nearly trashed bb

FishFish

I took the cranks off - a Shimano Deore with that plastic tensioner. It was in a Hope BB .

I tapped - and I mean tapped - nothing hefty the nd axle with a rubber mallet and the whole drive side came out. Axle and BB! The BB had stripped in the frame shell and some damage to the frame as well.

I took the thing to bits because I needed to replace the worn out pedals and thought I'd clean it up. There was no play in the axle or bearings but the drive side was completely stripped.

I did have a spare shimano bb which screwed in both sides but I guess that is the last life left.

Any idea what could have happened? I'm really careful when putting on BB and cranks and I'm sure that I must have fitted the bb myself - I would never overtighten but maybe too loose?

The Rookie

No idea, never had it happen with an English BB of any kind at all like that, had some with corrosion making it hard to undo but never ever just pushed out.

FishFish

I've been told that the bb bearings on the drive side may have been put in too loose and if so over the year or so without service (and a lot of miles (and I estimate 1.5 million turns of the pedal!)) the pedalling action has worn the bb threads / frame threads by very slightly rocking them. Which seems to make sense as the threads furthest from the frame have been affected most. Wonder if it did the same to my knees!