Worn spindle - BB30 and SRAM Rival crankset

[Twilkes]

After creaks and clicks, I removed the SRAM Rival crankset from my Cannodale to find the following wear:

* The drive side on the right, where there is still black surface, is the least worn, with a smooth surface left to right and a width of about 5mm; the non-drive side on the left has a definite ridge on either side that I can feel with a finger nail, and is 6mm wide:



* On the other side of the spindle, it's the opposite - drive side has a deeper ridge and is 7mm wide ; non-drive side is reasonably smooth and 5mm wide,



* Might be able to see the extent of the drive side ridge in this photo:



So what could have caused this wear - is it just worn bearings (one of the old bearings could slide loosely across all of the spindle, the other was still fairly tight) or could it have been installed incorrectly in the first place? The LBS had used two washers and a wavy washer which the SRAM guide says aren't necessary for BB30 installation, but it would have added 1-2mm to the non-drive side at most so I'm not sure how much difference that would have made.

Fitting new bearings and new crankset tomorrow so hoping that the frame wasn't affected by any of this, I can't see any particular wear in the shell or the outside of the old bearings. At least I've got the tools to maintain it myself now if any noise comes back.

 

[fossyant]

Your crankset is toast. I'll tell you what's most likely caused it.

SRAM bottom brackets aren't the best (understatement), they need regular re-greasing - not difficult, a pin to pop the seals off. What you've got there is seized bearings and the axel spinning on the seized bearing. It's worn the axel. As these axels are rather thin, I'd get rid, plus you've enough missing material not to marry up with the new bearings properly, introducing more movement.

I've changed to a Praxis Works GXP BB, and it's much better but still needs looking after.

 

[fossyant]

I see you are getting new. Before fitting, pop the seals of and shove extra grease in, then make it a regular job to pull apart and grease. Every few months (depending upon conditions). Fortunately, it's not a big job.

 

[Twilkes]

Your crankset is toast. I'll tell you what's most likely caused it.

SRAM bottom brackets aren't the best (understatement), they need regular re-greasing - not difficult, a pin to pop the seals off. What you've got there is seized bearings and the axel spinning on the seized bearing. It's worn the axel. As these axels are rather thin, I'd get rid, plus you've enough missing material not to marry up with the new bearings properly, introducing more movement.

I've changed to a Praxis Works GXP BB, and it's much better but still needs looking after.

Yeah I've got a new crankset to fit, updated the OP to reflect that. The old bearings were still spinning so I'm not sure they're seized, there was tilting movement in the cranks though, which I didn't catch in time, which lead to a creak when pushing down on the drive side, I'd thought that would explain the uneven wear around the circumference of the spindle.

Do you mean a Praxis adapter to take a different kind of axle, like the converter to take a 24mm Shimano crankset? I might do that next time but I was already knee deep in parts and tools this time, it's been an education though.

 

[fossyant]

Yeah I've got a new crankset to fit, updated the OP to reflect that. The old bearings were still spinning so I'm not sure they're seized, there was tilting movement in the cranks though, which I didn't catch in time, which lead to a creak when pushing down on the drive side, I'd thought that would explain the uneven wear around the circumference of the spindle.

Do you mean a Praxis adapter to take a different kind of axle, like the converter to take a 24mm Shimano crankset? I might do that next time but I was already knee deep in parts and tools this time, it's been an education though.

I have a complete Praxis GXP BB -not a converter. Still running Sram cranks.

 

[gbb]

Looks like the tolerance between axle and bearings was too big, axle rotating inside the inner ring of the bearing. Manufacturing defect perhaps.

 

[Milkfloat]

I seem to recall @Globalti having the same issue. See this thread https://www.cyclechat.net/threads/cannondale-bb30-bottom-bracket.196684/page-3#post-4207483 I have had a few BB30 and BB30A bikes and never had the same problem.

 

[Twilkes]

I seem to recall @Globalti having the same issue. See this thread https://www.cyclechat.net/threads/cannondale-bb30-bottom-bracket.196684/page-3#post-4207483 I have had a few BB30 and BB30A bikes and never had the same problem.

Yeah I've read that a few times - still not sure about Loctite between the crank and bearing, but will definitely put it between the bearing and shell.

 

[Twilkes]

I have a complete Praxis GXP BB -not a converter. Still running Sram cranks.

Does that BB fit inside a BB30 shell with no alteration or converter? Might look that up for next time.

 

[Darius_Jedburgh]

Yeah I've read that a few times - still not sure about Loctite between the crank and bearing, but will definitely put it between the bearing and shell.

My LBS abhors the idea of Loctite between the bearing and the shell. He is adamant that creaks do not come from there. All he uses is a thin smear of copper grease to ease future removal. Bearing fit compound on the axle if wear is showing. And good quality bearings - not the cheapest, but neither are ceramic needed.
Following his advice mine stopped creaking when knackered bearings were replaced.

 

[fossyant]

Does that BB fit inside a BB30 shell with no alteration or converter? Might look that up for next time.

No it's for standard screw fit BB's - just better bearings than SRAM use.

 

[Cycleops]

I seem to recall @Globalti having the same issue.

Haven't heard from him for a while. Hope he's okay up there in remotest Scot's Land.

 

[Twilkes]

Okay so new bearings and crankset, greased everything, there's no play in the cranks with a preload adjuster and a wave washer, and it spins smoothly, so all good so far. Will test ride later on. At least it should be easier to get everything out if there's just grease there, if any noise/friction comes back I can try Loctite between the spindle and bearings, but then I'm not sure how I'd get the spindle back out apart from hammering it hard, as there's no crank removal tool that would do that, that I'm aware of.....

 

[fossyant]

Don't use loctite.

 

[T4tomo]

BB30 issues, say no more.