External Bottom Bracket Lifespans

[reohn2]

Just had another BB51 go after 1549 miles. This one was on my Genesis Longitude.....

Same hear at around 1000miles and that's despite me stripping and greasing the bearings from new then fitting/torqueing up as per instructions.
It started clicking which alerted me to the problem,on stripping one of the bearings was full of brown sludge

I replaced mine with a Token make which got some good reviews,though I haven't ridden it a lot since.

It seems some EBB's don't like wet/bad weather.

[mercalia]

what about a corresponding poll for normal ones?

[Mr Evil]

The last time I replaced one, it had done about 6k miles. I replaced it because the aluminium cups had been substantially eroded by galvanic corrosion with the titanium BB shell. The bearings were still ok. That had happened because there was no drain hole in the BB, and there were only clip-on mudguards on the bike, so water accumulated inside. I had used generous amounts of copper grease, and emptied the water out frequently, but it wasn't good enough.

I don't ride that bike in the rain anymore (except when it starts raining unexpectedly after I have already set out, which is actually quite often I suppose). The bike I do ride in the rain now has a PF30 BB which must have done about 9k miles and still feels as good as new.

[bikerwaser]

what about a corresponding poll for normal ones?

I think it would be a good idea to know what BB's are giving the low or high mileage

As I've mentioned, every Shi!mano BB51 has given me (and my friends) between 800 miles and 2200
But My Hope BB is still going strong at around 10,000

[RickH]

what about a corresponding poll for normal ones?

I think it would be a good idea to know what BB's are giving the low or high mileage

As I've mentioned, every Shi!mano BB51 has given me (and my friends) between 800 miles and 2200
But My Hope BB is still going strong at around 10,000

The OEM Race Face EBB on my Kona developed play after about 500 miles or so. Despite the fact that they boast being packed with Phil Wood grease (which at least makes it sound like a good thing) various reports online reckoned the bearings themselves were made of cheese (or sentiments to that effect). My LBS agreed & fitted a Shimano SM-BB52 instead which is still fine another 1300 miles later. The BB52 is supposed to have better seals than the BB51, how much effect that will have is yet to be seen.