Slightly worn Bottom Bracket

Old timer

Über Member
Location
Norfolk, UK
It` s been many years since I had to do much work on a bike so bare with me.

I noticed a small amount of play in my sq tapered bottom bracket. I dismantled it today to see if it needed grease and it did. There is a solid spindle with two lips. There are two ball bearing cages and as you tighten up and adjust it seems like the balls are pressed against the lips on one side and the inseide of the cups on the other. One of the cages let the bearings drop out as I dismantled it and one stayed intack(just) they are not actually proper roller bearings or even tapered bearing but just a loose fitting cage. Anyway, I cleaned and repacked with grease that held the balls in place till I reasembled. When I tighten up to remove any vertical movement there is a tight spot, if I slacken off to get rid of the tight spot there is a touch of vertical movement at one spot of the revolution. Total mileage of the bike is maybe 500 miles. I`ve managed to tighten up to a compromise (just enough to feel the tight spot when turning the BB spindle by hand but not enough to feel when the cranks are back on.) It`s quite a long spindle and one side from the lip is about 5mm longer than the other( the crank side is the longest I gather)

What next? just ride and see what happens or replace the bearing cages and cups or can I convert to a more modern all in one assemble and where are they available.

Thanks for your help

BTW I don`t do vast mileages on the bike, maybe 1,000-1,500 miles total per year

Dave
 

battered

Über Member
I'd keep an eye on it for now and ride it. It's low risk after all, worst possibility is that the whole thing wears out. If that happens you are no worse off.

I would imagine you could fit a sealed unit BB, a LBS can advise size and type. For now though I'd just sick it and see.
 
Location
EDINBURGH
BB's are as cheap as chips, Accor do a good range of low cost tapered BB's with sealed bearings so have a look for one of them, your existing BB is a low quality unit and one of the bearing seats is pitted, eventually it will crack and seize.
 
OP
Old timer

Old timer

Über Member
Location
Norfolk, UK
OK, thanks. I`ll ride it and see how it goes and as you say it will show up before it breaks anyway and then I`ll source something sealed.
 
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