About how many miles does a bottom bracket last?

donrhummy

I have a bontrager giga x pipe 7050 powerglide crankset+BB for a road bike. I try to only ride it in non-wet weather. I get caught in the rain maybe twice a year on this bike, so that should be OK. I do mostly long rides with some climbing, but nothing like sprinters do. I was wondering how many miles a BB like this can be expected to last.

bhm100

The modern sealed units last for years as far as I'm concerned.

I can only think of replacing one on my MTB, the ones on my road bikes have become redundant before wearing out. In mileage terms it must be 20,000plus, so nothing to worry about just yet !

giant_man

I'm just about to replace my record bb and it's five years old soon, so not too bad really.

shazzz

They vary!!!

To test, unship the chain from the chainset and give it a spin. If it's nice and smooth then all is well. If it feels rough then you should think about changing it.

gkerr4

i had a 'ISIS' type road BB go on me in about 800 miles - although the last 150 of those were an unbelievably wet & muddy coast-2-coast trip in may last year. I think it got water inside and rusted all the bearings - could have complained as the bike was only a few months old - took the 'opportunity' to upgrade to a hollowtechII unit which is great.

I believe the 'ISIS' types were renowned as being crap though - something to do with large axles and tiny bearings

donrhummy

Thanks for the replies! I think there might be some creaking when I'm going up hills so I'll take the chain off and try spinning it.

Any recommendations for a good BB that'll work with bontrager/truvativ?

gkerr4

it could be the same thing - I had a trek pilot with a truvativ crankset

if it is a ISIS - my only recomendation (based on my ad experience) would e to replace the whole crankset with the holowtechII stuff - I ended up paying under £50 for the whole new chainset and BB - a tiagra triple HT2 unit when a new ISIS BB was going to be over £35 for a decent one.

Yorkshireman

Just changed a Shimano UN 52 (new chainset needed a different BB) that has at least 55,000 on it (over 8 years), and it's as smooth as silk - no play. Hope the UN 53 that replaced it lasts as well.