Use the thickest flat washer I can find on everything...lock washers, start washers,...I have just never had any luck with them.
clean the threads and inside the nut really well with brake clean.
Shake up the threadlock.
Then tighten them down tighter than you think. then hit them again with more torque.
The best advice I ever received about tightening bolts on specialty cars:
Go back and loosen off some of the bolts you had just done- you will be shocked at how "untite" they are. Reason is everything is covered in new paint and chrome, you have a lot of time invested. broken, stripped stuff is expensive. You are barely going over finger tight with the torque because you dont want any problems or ruined paint, you dont realize your doing it but you are.
Try to think of your beautiful bike as a dirty old street sweeper while you are torquing things down.
Lee