[sysanalyst--off]

Try some Loctite Green. That should keep that bolt snugged down. Are you using a lockwasher under the bolt head? May want to try that too. You certainly don't want that clutch to become separate from the crank snout or you will have a lot more to worry about than torquing a bolt and using some Loctite!

Good luck.

FYI: Loctite doesn't affect torque/bolt yield; it just glues the threads together.

 

[sysanalyst--off]

Maybe clutch rebuild/replace time. How many miles on that primary? Possibly a broken spring.