Loosening bolt in non-drive side

[k0p4n]

Hello boardmembers,

I recently upgraded my bottom bracket and crank set.
The bottom bracket is sealed and I was told that this bottom bracket and crank set were made with JIS standards.

Anyway, the my older bottom bracket used a nut to hold the crank in place while this new bottom bracket uses a hex bolt to hold the new crank in place. The thing is, on the non drive side, I have to turn the bolt clockwise to tighten, likewise for the drive side.

As I ride my bike, mostly while standing to give more force, the non-drive side bolt loosens because as everyone knows, the non-drive side turns counter clockwise.

Therefore, the bolt loosens. I was thinking maybe I should take a rubber mallet and hit the crank inward more to then tighten the bolt but I came to ask if my bottom bracket was broken. Is it?

I appreciate your help.

[Painkiller]

If it is new and properly torqued it should not come loose. makes no difference if you have a nutted spindle or a bolted spindle. If your crank is rotating enough to loosen the bolt/nut it could be damaged or not seated properly.
I understand what you are saying about the non- drive side and rotation, but with your crank arm it does not matter. yours just happens to be on that side. When torqued properly you are pressing the crank onto a spline and need a puller to remove it.

[k0p4n]

Thanks
I also read elsewhere that this could be due to being goofy footed, leading with the right foot.
I'll test it out as well as make sure the crank arm is on right.

Thanks again

[nfmisso]

As pk noted; if the crank arms are properly installed, the bolt (or nut) does almost nothing.....and even if you removed it, you could not pull the crank arm off without a tool.

[DaveM]

The left crank arms tends to loosen easier than the right because the chain on the drive side absorbs a lot of the pedaling force. On the left, all the force goes thru the crank/spindle junction to get to the other side. So it is under higher loads. That said, as above, a properly seated and tightened crank arm should not loosen. Using a hammer will just damage the bearings. Use a torque wrench.