Never. I have a shimano BB that got to have 80k on it and its smooth and my newer bike has 20k on it and it too is smooth. I guess i did flush my chris king bb on the mtb with new grease once, but that was just to see how their tool worked. From my experience , unless your riding in mud, BBs are pretty service free
2 Likes
If the grease is in there, leave it alone. If the grease is not in there, your bearing is already screwed.
During cross season, I pull it once or twice a month to clean and check it. On all my other bikes, I check if if it starts making noise or feeling gritty… which is to say I pretty much don’t touch it
3 Likes
somewhere between yearly and when its making noise.
1 Like
usually about twice a year with a lot of volume.
If things feel off, or I can hear a creak, get it cleaned up, and they’ll let me know if i need a new BB.
My old bike has had the same BB for years, just gets cleaned up slightly more often, my newer bike, I took it in for a routine “it’s creaking” and it was toast .
C’est la vie
1 Like
Probably goes without saying, but this is highly dependent on the bike and how you use it.
Road bike might never need it.
MTB that gets dunked in a mud pit up above the BB or sees lots of wet? Frequently. (This is the scenario where an aftermarket one that’s easily serviceable makes a lot of sense)
1 Like
IMO taking the seals out to ‘flush and repack the bearings’ is asking for problems. I remember my skateboarding days and people would do that with their bearings, and it often just shortened the life of them. I used fully sealed bearings, which were slower, or just used the bearings until they were trashed and then just tossed them. For my bikes, I haven’t ‘serviced’ a bottom bracket yet. I have swapped bearings, and in one case swapped the type of bottom bracket to avoid squeaking, but ‘servicing’ bearings that are sealed is paying for a service that isn’t necessary and needlessly inviting more issues IMO. Plus, if the seals in a bearing are removable, is it really ‘sealed’, or ‘semi-sealed’, and do they replace the removed seals, or let you think that the removed seals aren’t going to fall out, or weren’t damaged potentially ruining the bearing. The only thing that I do is run some Phil’s on the outside of bearings, acting as another seal/deterrent to foreign substance ingress.
But I was disappointed that the bottom bracket on my Neo Bike isn’t replaceable by mere mortals. It looks to be a somewhat standard setup, I’m just concerned that the constant bath of sweat is working its magic to limit its lifespan. I’d hate to have to swap most of the bike just for something I likely have (most of) the tools to replace.
But I take the replace when failure is imminent, or has occurred with bearings and chains. Popping seals seems to be inviting problems…
And anyone else thing that Park Tools have seen their best days? Some of the more recent tools I’ve bought are just Chinese knockoffs and the quality is just not there, sadly…
But it’s all about your comfort level, and case base. I have known people that have had their bikes serviced often and experienced problems just because of the service. I think you can ‘over service’ things, and disturbing mechanical systems that are working fine can invite problems. If it’s lose, torque it. If it’s broken, replace it. If it works fine, leave it alone.
1 Like
Only time I “serviced” a BB was because my square taper crankset developed a wobble and I switched to Hollowtech. That’s on a bike I’ve had for a decade now.
2 Likes
Never. If I go through the effort of removing a bearing, I’m putting a new one back in.
Ride it til I can hear/feel some resistance in it, then replace it. Sometimes it’s a year, I’ve had them last as long as 5 years.
1 Like
Hmm. I’ve been having a lot of creaks iny bottom bracket lately, especially after rain. I’d assumed it was from the threads and pulled the bracket out and greased the hell out of the threads.
Wondering if the thing might just be cooked now…
1 Like
Thank you.
1 Like
Check for loose cranks. That will do far more to save your bike than performing surgery on them. But YDY…
Loose cranks would certainly be a problem – fortunately not one I’ve ever had. Depending how long it was operated in such condition I could certainly see that requiring full replacement of the bearings/bb.
And potentially the whole crank too. (The crank on earlier Neo Smart Bikes I’ve had would loosen up constantly. This last one seems rock solid. The bb on those is not easily replaced too, sadly)
Reminds me: I was on a ride when someone’s left crank arm ‘just came off’, ‘totally out of the blue’. No one believed it because when it gets that bad, it’s got to be completely noticeable before it ‘just falls off’.
Excellent point on the crank-axle also possibly getting ruined. My mind also boggles how someone wouldn’t notice their crank coming loose. A senior riding buddy of mine had that happen, but he doesn’t service his own bike so I can’t strictly blame him.
I’ve once killed the bearings in my tacx neo v1 freehub 
1 Like
Did you have to send it in to get it fixed, or were they selling the parts at that time. I burned out the hub bearings in our gen 1 Peloton. I swapped the bearings in the old hub after it was replaced. The guys that came to swap it said ‘we aren’t supposed to leave it, but all we do is throw it out when we get back to the shop, so here, have fun with it’. 
I ordered a new freehub from (now) Garmin (original lasted 5 years so I wouldn’t call it warranty-worthy). The bearings are technically replaceable, but I guess a little difficult to get out of the revision that came with my neo. I’ve kept it on hand with the intent to remove the bearings so in case the new one fails I can just get some cheap bearings and swap the old one back in.
1 Like