Loctite?

[battered]

Washers, certainly plain and spring washers, actually increase the chances of a screw untightening.
Loctite comes in various different strengths, of course. 222 is probably the most appropriate stuff for bikes. 243 is a bit strong, and 272 is as good as welding the thing up, so not recommended.

+1. Threadlocks come in all sorts of colours and shapes and sizes. I use common or garden stuff on all sorts, it's a shakeproof joint, it prevents corrosion so it's an anti sieze compound, and it doesn't affect your torque/tightness settings (unlike grease), what's not to like?

 

[Ian H]

Washers, certainly plain and spring washers, actually increase the chances of a screw untightening.

Weird. 30 years of fettling bikes and twenty years of playing with heavy print machinery leads me to a different conclusion. But there you go.

 

[Proto]

That will probably be grease.

No, that will be thread lock.

Usually applied at the time of bolt manufacture in the form of a 'patch'.

Personally, I use Loctite Threadlock or Screwlock on crank bolts, especially those on the ends on FSA ISIS type bottom brackets and FSA SLK Mega Exo types, although I also use it on Campag Ultratorque crank axle joining bolts.

 

[BrumJim]

Weird. 30 years of fettling bikes and twenty years of playing with heavy print machinery leads me to a different conclusion. But there you go.

Experience is with zinc coated fasteners on railway vehicles and no lubrication. Zinc plating plays havoc with the coefficient of friction, so anything that further increases the variability is bad news. Problem is that there is a lot of established practice around, and only some of which can be backed up by evidence. Some people still think that spring washers improve resistance to untightening. Unfortunately they do the opposite, but do increase the strain energy of the joint. However something like a dome or Belleville washer does both jobs much better.

 

[Alembicbassman]

my disc brake shoe securing bolt has threadlock applied to it, I replaced them and applied a new coat of the blue solution to the bolt.

 

[AlanW]

Weird. 30 years of fettling bikes and twenty years of playing with heavy print machinery leads me to a different conclusion. But there you go.

By the same token, 30 years of engineering has taught me that you should NEVER fit spring washers and flat washers together. If you think about it, what does the spring washer "bite" in to if there is a flat washer underneath it?

 

[AlanW]

Cleat bolts!

No way, its bad enough trying to remove a cleat screw when the head has rounded off?

In fact every since then I do the complete opposite, I apply a coating of anti seize compound to all three screws. And during the salty winter months, I will reapply a couple of times.