I’m not quite sure why but my preload cap keeps unscrewing itself from my crank. Everything is tightened to proper specifications using a decent torque wrench. This is the old one not the type S without a cap. I’ve double checked everything a couple times and can’t make heads or tails of why it happens. Any ideas?
I’m not quite sure why but my preload cap keeps unscrewing itself from my crank. Everything is tightened to proper specifications using a decent torque wrench. This is the old one not the type S without a cap. I’ve double checked everything a couple times and can’t make heads or tails of why it happens. Any ideas?
Just taking a wild guess here but shouldn’t you torque it down a bit tighter after the left crank arm is clamped down tight to the axle? Start with it loose enough for the correct preload. Then tighten the crank arm down tight and finally snug the preload cap a tad more?
YMMV,
Hugh
I’m not quite sure why but my preload cap keeps unscrewing itself from my crank. Everything is tightened to proper specifications using a decent torque wrench. This is the old one not the type S without a cap. I’ve double checked everything a couple times and can’t make heads or tails of why it happens. Any ideas?
Just taking a wild guess here but shouldn’t you torque it down a bit tighter after the left crank arm is clamped down tight to the axle? Start with it loose enough for the correct preload. Then tighten the crank arm down tight and finally snug the preload cap a tad more?
YMMV,
Hugh
I’ve tried tightening it back up beyond the preload a couple times when it works loose after verifying the arm bolts are still tightened properly so I’m thinking that’s accomplishing the same thing. Somehow it is finding a way.
Try locktite!
I guess I’ll have to though it did come with blue stuff on the threads already.
Just because old glue is on the threads, doesn’t mean it’s doing much anymore.
Hopefully someone has a good answer, because mine does the same damn thing!
I’ve already cleaned the threads and applied new locktight…
This was a common issue with the older FSA cranks that used pinch bolts on the left arm, probably the reason FSA dumped the design a few years ago. I had the same issue with both P2M and standard Gossamer cranks, what eventually worked for me was every time the bolt started to work loose, I’d remove it and add more Loctite. After a few applications, none of my cranks are working loose any more…
This was a common issue with the older FSA cranks that used pinch bolts on the left arm, probably the reason FSA dumped the design a few years ago. I had the same issue with both P2M and standard Gossamer cranks, what eventually worked for me was every time the bolt started to work loose, I’d remove it and add more Loctite. After a few applications, none of my cranks are working loose any more…
The thing that sucks for me about this is that I need to swap the crank relatively frequently between a road and tri bike. Is there another way?
I have this same setup on both my bikes and my wife’s bikes. Mine never comes loose, hers does frequently. I’ve just gotten in the habit of checking hers frequently and tightening it up when it happens.
This was a common issue with the older FSA cranks that used pinch bolts on the left arm, probably the reason FSA dumped the design a few years ago. I had the same issue with both P2M and standard Gossamer cranks, what eventually worked for me was every time the bolt started to work loose, I’d remove it and add more Loctite. After a few applications, none of my cranks are working loose any more…
The thing that sucks for me about this is that I need to swap the crank relatively frequently between a road and tri bike. Is there another way?
I don’t swap cranks back and forth that often, but once I got a good build-up of Loctite on both bolts and spindles, the problem went away. I haven’t needed to apply any new Loctite the last few times I swapped, and no issues with loosening…
I had this problem for ages too - tighten the preload cap, then make sure to tighten the inner (closest to the BB) bolt first then the outer bolt. This solved it for me- didn’t need loctite.
Interesting. I’ll have to try that.