After returning home from our cross country tour I started cleaning up our bikes. Today I pulled my cranks and after cleaning I put it back together. I noticed the left side of my BB has a lot of play. I have about 7,000 miles on it. So is there a typical life span ?

IMO- there's no "typical" life span. In the past, the traditional cup/cone BBs could last 30-50,000 miles or more, with some service every year or two (5-10,000 miles). Today's new and "improved" designs don't seem to last nearly as long, but I'd expect that they should do better than 7k. This is why I'm something of a Retro-grouch when it comes to BBs, and try to stick to the older systems. Their main virtue is that they could be serviced, and play, if it develops can be adjusted out.

+1

An external BB shimano should basically last years unless you just ride in mud and rain. I still like the external BB for simplicity and ease of change. Any problems for about $25 you get a new BB and continue to ride. The other stuff as FB say is correct. The new press fit I am find an unknown.

I'm a huge fan of the PF-51.3 set up... incredibly easy to adjust, supremely facile to rebuild, they accommodate a beefy 23.8mm spindle, and made-in-the-USA replacement BB sets cost a mere $8. Never measured the mileage i get out of'm, b/c i don't even remotely care about such things....

The item in question is a Shimano SM BB51. It seems they cost about $20. I was wondering if there might be a better quality BB?

Of course there are better BBs. I don't get involved in specific recommendations, but I'm sure some Shimano users will post suggestions.

Phil Wood & Co. ??

I've had really good luck with the cheap Shimano BBs, so......

So did you enjoy the trip ? now you are replacing worn parts that allowed you to enjoy the trip.. I wouldn't sweat it, if I were you.

get an after market brand , Phil, King. if you wish..


my solo tour frame was built around using an oversize internal bearing BB shell from Burly's 90 tandem rears.

The trip was great! we have a few more short trips yet this year. I am going with a Phil Wood.

phil wood or the chris king. the chris king has a grease tool to flush it out

There's also the SKF BB with roller bearings on the drive side, warranted for 10 years, comes with JIS, ISO (Campy), or ISIS ends, and costs about the same as a Phil Wood:

Compass Bicycles: Bottom Brackets

This is for a Hollowtech II crank, though....

The King BB is more easily serviced, but the Phil is far less likely to need servicing. I'm probably going to keep buying Shimano sets, but if i ever decided to splurge on a HT2 BB, i'd definitely go for the Phil...

You won't be happy with it. The bearings are the same type. It's not the bearings it's the design of the new and improved system.

Try the cheaper version of one of these. Avoid ceramic bearings. CUSTOM BOTTOM BRACKETS FOR HOLLOWTECH 2

just another option is the new xtr bb which has better sealing than the bb51 that you pulled. i have been happy with thedura ace 9000 andn ultegra br60 that we have been installing. these are the same design