Had a strange failure about half a mile down the road after finishing the Marin trail on Friday - very lucky it wasn't half way round!
It seems a small stone got struck between the granny ring and the driveside cup of the BB, unscrewing it (there's a deep gouge in the cup). Once it started unscrewing, it would obviously get stuck as the crank was still on and couldn't unscrew any more. Back pedalling wound it back in a bit, but without a 10mm hex key and BB spanner it was out of action for the rest of the weekend. Anyone else had this happen?
It was a superstar BB (2 years old and otherwise still going strong) and raceface evolve XC crankset, similar age.
Cheers!
Unlucky but it you've proved it can happen.
Sounds like an unfortunate pure fluke.
yeah thats actually happended to me with a hope bb, completely my fault...fail on spacers/fitting/tightening up caused it to unwind as i pedalled...uber lame. Up nice and tight next time 😀
Does seem pretty unlucky, but I'm surprised it's not more common, as there's only about 3-4mm between the BB cup and the inner edge of the granny ring.
Scares me a bit how loose you do up these bottom brackets what with the plastic spacers which begin to extrude when you tighten them up.
I wonder if the cup was a bit loose in the first place?
It may have been a bit loose, but it was only fitted a few months back. The plastic spacers get squashed pretty easily, especially if the BB shell is steel (i.e. thinner than aluminium)
It may have been a bit loose, but it was only fitted a few months back. The plastic spacers get squashed pretty easily, especially if the BB shell is steel (i.e. thinner than aluminium)
Plastic spacers are cack. Get some alloy ones in there! Shimano ones are alloy.
Any, still, twas a tad unlucky 🙂