The screw in cap used for setting tension on the non-drive side crank seems to try to unscrew itself during a ride.

Should it stay put? I’ve tried some blue threadlock, which helped, but its still started to unscrew itself.

Any ideas?

My strategy on thisbstylr crank arm mount is install cranks, turn bolt to required spec (very low torque as this only serves as per load) then tighten crank arm cinch bokts to torque. Remove cap and blue thread lock the over tighten against already tightened crank arm so you are not adding more preload. Mixed results, sometimes no matter what you do these seem to continue to loosen

Thanks, will give it another go.

Seems a crap design if its likely to keep trying to unwind itself.

I had these years ago and I successfully rounded off the cheese like preload allen key hole in the cap. I found cutting a large screwdriver slot far more effective. IMO – they are pants. Blue threadlock is an excellent suggestion.

If its only used for setting the pre-load, could I just take it off after I’ve done the tension?

(Or are the pinch bolts not to be trusted and the crank arm will fall off without it?)

aaaannndd, surprise, surprise, the allen key hole rounded out on this tonight.

Luckily, seeing as though it has penchant for unscrewing itself, it will probably just take a few rides before it unthreads itself, and I can either take the hacksaw to it to try and cut a slot in it or fit a replacement

I also had these years ago – on 2 bikes. Both developed small cracks on the gnarly bit of the drive-side where the pinch bolts clamp.

It could have been from over tightening – but i’ve not had trouble with any other cranks, so probs not. And yes, the pre-load cap is pants.