Bottom bracket wear

[KrispyK]

Hey all,

I have been having what I think is some excessive BB wear over the past year and half on my track bike. I run a SRM Origin track aluminum with the steel 24mm spindle. My frame is a open mold carbon track frame with BSA threading. I have chased and faced the BB to ensure proper fitment. In the past year and half I have gone thru 3 bottom brackets/bearing sets. I originally had a Dura ace bottom bracket which last about 2 months. Then I switched to Wheels MFG with the ABEC 3 bearings as that was what was in stock at the time. Those lasted 2 months. I have now switched to the Wheels/Enduro angular contact bearings in the same cups. Those have lasted the until now but are now starting to wear out.

I am track sprinter so lots of hard standing starts and accelerations but I only ride in dry conditions so water is not an issue. It seems like I go through bearings at an excessive rate. My training partner has the same issue with the same setup.

Any bearing recommendations or other suggestions? Maybe get a BB with a life time warranty?

Or is this what comes with being a track sprinter?

[11.4]

That's definitely abnormal and I'd have to point at installation as a problem. None of those bottom brackets (and none using an SRM crank) cause problems on the track, even after years of elite power use. One odd failure could be a manufacturing defect, but I'm not even sure what's happening here. Can you explain more specifically what the symptoms are, include photos, etc.? I'd have a high quality shop install a new bottom bracket and just use a Dura Ace because it's cheap and reliable. But before doing any of that please provide a lot more detail on how it fails.

[KrispyK]

Originally Posted by 11.4

That's definitely abnormal and I'd have to point at installation as a problem. None of those bottom brackets (and none using an SRM crank) cause problems on the track, even after years of elite power use. One odd failure could be a manufacturing defect, but I'm not even sure what's happening here. Can you explain more specifically what the symptoms are, include photos, etc.? I'd have a high quality shop install a new bottom bracket and just use a Dura Ace because it's cheap and reliable. But before doing any of that please provide a lot more detail on how it fails.

Mode of failure is that the bearings start to become notched and is noticeable when I spin the cranks without the chain on. I would like to think that I work at a high quality shop and had have other mechanics check out my installation of bottom bracket and cranks just to be sure.

[prototoast]

On your frame, are left and right threaded inserts cut out of a single piece or two? If the latter, they are probably not perfectly aligned with each other, which is putting extra stress on your bottom bracket. I'm not sure any particular bottom bracket would fix your problem. Shimano bottom brackets tend to be the most forgiving of poor frame tolerances, so you probably actually making it worse by switching to Wheels MFG.

If you want to stick with your frame, I suggest going with the cheapest Shimano bottom bracket you can find, and replacing them as often as necessary.

[bikeboy1]

If your training buddy is having the same issues with the same frame then I would think there is some kind of misalignment in the BB shell and thats normally what these one piece BBs are supposed to solve with that particular issue. I just wonder how difficult the BBs where to install? This is just an assumption as more info is needed.

[mjf]

Originally Posted by 11.4

That's definitely abnormal and I'd have to point at installation as a problem. None of those bottom brackets (and none using an SRM crank) cause problems on the track, even after years of elite power use. One odd failure could be a manufacturing defect, but I'm not even sure what's happening here. Can you explain more specifically what the symptoms are, include photos, etc.? I'd have a high quality shop install a new bottom bracket and just use a Dura Ace because it's cheap and reliable. But before doing any of that please provide a lot more detail on how it fails.

Krispy is a mechanic, arguably at one of the best shops in SD. I can promise that it being installed to spec isn't an issue.

Frame had been prepped chased/faced appropriately when it was being built, and subsequent replacements down the line were installed appropriately.

Originally Posted by prototoast

On your frame, are left and right threaded inserts cut out of a single piece or two? If the latter, they are probably not perfectly aligned with each other, which is putting extra stress on your bottom bracket. I'm not sure any particular bottom bracket would fix your problem. Shimano bottom brackets tend to be the most forgiving of poor frame tolerances, so you probably actually making it worse by switching to Wheels MFG.

If you want to stick with your frame, I suggest going with the cheapest Shimano bottom bracket you can find, and replacing them as often as necessary.

This is the one sticking point that I think.

If I'm remembering correctly, the frame has separate L/R sleeves, and I'm also leaning toward the cups in the frame not being aligned properly. Not much of anything that can really be corrected outside of the frame being modified.

[45K10]

I would bet it's an alignment issue. I had a Ridley road frame some years back that went through bbs every three months or so. It had separate threaded sleeves bonded into the frame. I assumed it was an alignment issue. Other than that issue the bike was great and fit me well so I would just stock up on Shimano BBs when they were on sale.

Tangentially, I have never had much luck with Wheels MFG bottom brackets. They never seemed to last as long on any of my bikes, even the PF ones as long as a Shimano ones would last.

[billb5612]

you might want to check out Hambini and his bottom brackets. very expensive but may solve the problem. check out his videos on youtube, they are hilarious and informative. if you don't mind a lot of British cussing.
https://www.youtube.com/@Hambini/videos

[KrispyK]

Originally Posted by billb5612

you might want to check out Hambini and his bottom brackets. very expensive but may solve the problem. check out his videos on youtube, they are hilarious and informative. if you don't mind a lot of British cussing.
https://www.youtube.com/@Hambini/videos

TBH I like the products he sells but I cannot stand his internet personality. I find it very hard to buy things from someone who cannot stop swearing.

I have had his one piece bottom brackets fix a few creaky frames I've worked on.

[KrispyK]

Originally Posted by 45K10

I would bet it's an alignment issue. I had a Ridley road frame some years back that went through bbs every three months or so. It had separate threaded sleeves bonded into the frame. I assumed it was an alignment issue. Other than that issue the bike was great and fit me well so I would just stock up on Shimano BBs when they were on sale.

Tangentially, I have never had much luck with Wheels MFG bottom brackets. They never seemed to last as long on any of my bikes, even the PF ones as long as a Shimano ones would last.

I had a feeling it might be an alignment issue. The frame was pretty cheap. it is has separate sleeves bonded in.

If all I need to do until I get a new frame is to replace the bearings for $20 every 6-8months its not the worst thing. not ideal though.

I have had good luck with my other Wheels MFG bottom brackets. I install them for a lot of customers with good success.

[prototoast]

Originally Posted by KrispyK

I had a feeling it might be an alignment issue. The frame was pretty cheap. it is has separate sleeves bonded in.

If all I need to do until I get a new frame is to replace the bearings for $20 every 6-8months its not the worst thing. not ideal though.

I have had good luck with my other Wheels MFG bottom brackets. I install them for a lot of customers with good success.

Wheels MFG bottom brackets are good, but they use bearings pressed into aluminum. Shimano pressed their bearings into plastic. The advantage of Shimano is if the two sides are a little out of alignment, it's easier for the bottom bracket to adjust to accommodate. I like the wheels mfg thread together bottom brackets for press fit, but for threaded bottom brackets, I find they're very sensitive to the tolerances of the frame.

Originally Posted by KrispyK

TBH I like the products he sells but I cannot stand his internet personality. I find it very hard to buy things from someone who cannot stop swearing.

I have had his one piece bottom brackets fix a few creaky frames I've worked on.

I don't think Hambini bottom brackets could help much here. Where his bottom brackets really shine is with press fit because the one-piece aligns the whole system to one side, so doesn't matter as much if the frame isn't perfectly aligned between the left and the right. With threaded bottom brackets, even the Hambini bottom bracket option puts the two cups in independently, and would likely give you the same problem.

[KrispyK]

Originally Posted by prototoast

Wheels MFG bottom brackets are good, but they use bearings pressed into aluminum. Shimano pressed their bearings into plastic. The advantage of Shimano is if the two sides are a little out of alignment, it's easier for the bottom bracket to adjust to accommodate. I like the wheels mfg thread together bottom brackets for press fit, but for threaded bottom brackets, I find they're very sensitive to the tolerances of the frame.

I think ill replace the Wheels with a Dura-Ace when the bearings wear out this time around.

[oldpotatoe]

Originally Posted by KrispyK

I had a feeling it might be an alignment issue. The frame was pretty cheap. it is has separate sleeves bonded in.

If all I need to do until I get a new frame is to replace the bearings for $20 every 6-8months its not the worst thing. not ideal though.

I have had good luck with my other Wheels MFG bottom brackets. I install them for a lot of customers with good success.

If the left and right cuts aren't 'parallel', I'm surprised it doesn't feel draggy in your hand, spinning with fingers, before installing cranks. Of the frame si have seen with this, the BB barely turns after it's installed.

I think ill replace the Wheels with a Dura-Ace when the bearings wear out this time around.

Octalink? Use an Ultegra 109.5mm BB. Or even 105..Might not hold up to your event but cheap.

[mjf]

Originally Posted by oldpotatoe

If the left and right cuts aren't 'parallel', I'm surprised it doesn't feel draggy in your hand, spinning with fingers, before installing cranks. Of the frame si have seen with this, the BB barely turns after it's installed.


Octalink? Use an Ultegra 109.5mm BB. Or even 105..Might not hold up to your event but cheap.

Hollowtech,SRM crankset

[11.4]

What happens if you use a bulletproof cartridge bottom bracket like a BB7710 (basically the old 7700-era Ultra bottom bracket) and a pair of Octalink cranks. I know you lose your power meter, but try it for a month or two and see what happens.

You had mentioned you used the high-end Wheels annular bearing set, yet it also failed on you. If the issue was a skewed bottom bracket, that Wheels bottom bracket should at least have minimized bearing failure.

Is your chainring perfectly planar through a crank rotation? If your bottom bracket shell is forcing the bottom bracket out of alignment, shouldn't it be reflected in an out-of-plane chainring?

Last, SRM has had episodic problems with bottom bracket milling being slightly off kilter -- their Octalink bottom brackets sometimes weren't concentric so one crank would bring the pedal in and out during a crank rotation. The same happened with their later Dura Ace models (hollow shaft) and was almost a chronic problem in tapered square spline days. This has mostly been seen on track cranks, possibly because they are not a high-volume product and cranks were milled more by hand. Long shot that the crank is out of alignment? I'm not sure that it should be killing bottom brackets like this, but looking for issues.

I've worked with track cranks for over forty years, and almost exclusively with track equipment. I might even have been at it longer than Old Potatoe. I'm always discovering new things, but in all that time, with a lot of screwy track frames, haven't seen a failure rate like you describe. It's got me curious and I'd love to know how you diagnose it in the end and how you fix it.