tyrion

Is there a list of rules of thumb about how thead locks and lubes should be used in combination?

For instance it seems you don't put grease on the pre-loctited rotor bolts but you do put grease on pre-loctited BB threaded bearing.

What are the rules here?

trailangel

I say one or the other, not both. My preference is threadlocker. Some people that ride in wet climates.. PNW, NE, SE... maybe they would use grease instead and rebuild more often.

tyrion

So if you get new BB threaded bearings with factory applied loctite already on them, you don't grease them up?

dsbrantjr

I put grease or Tef-Gel on all joints which do not have pre-applied threadlocker. Generally, properly-designed (not all are) and torqued joints do not require threadlocker although there are of course exceptions.
I do use elastic stop nuts or Vibra-Tite VC-3 Threadmate on things like racks and fenders but stay away from threadlockers unless directed by the manufacturer.

I also make frequent use of torque wrenches.

Troul 

I use anti seize for bb threads.

CyclingFool95 

I just completed a bike build with not a drop of Loctite but plentiful anti-seize on everything. Apparently that puts me afoul of Campagnolo's instructions in their manual for the crankset. I figure I'll know its loosening up long before anything serious happens, but I won't know that something has galled or corroded (galvanically or otherwise) until it's much too late.

3alarmer 

...one of the reasons you get so many divergent opinions on this is that practice varies with climate, location, and general riding conditions for the machine in question.

Thread locker (regular Loctite types, not some of the other ones) doesn't really work well in combination with grease or oil, and in fact if you read the instructions you'll see they advise cleaning the two surfaces to be joined before application.

There are not that many things I religiously use threadlocker on, but the drive side cup on an old style loose BB installation with RH threads (Italian and French types) is one of those things. But just grease on the adjustable cup threads. Phil recommends Loctite on the retaining rings for their sealed units (both of them).

Otherwise, mostly go with experience. Eventually you will have a lot of it.

CyclingFool95 

Bad practice perhaps, but I've never loctited the non-drive side on my Pinarello (and didn't yet again when I rebuilt it a few weeks ago - this time it was built with an old Chorus cartridge BB). The open ones have a lockring to hold the cup in place, the sealed ones do not - is the assumption that the friction betweem the cup/cartridge will hold it? - seems like those might be worse. In any event, when I disassembled it after 3500 miles followed by sitting around for 20+ years, it was still well retained by the lockring but the cup came out easily once the ring was removed. The drive side was a nightmare to remove, of course.

When I pulled it out after some 3500 miles followed by it sitting for 20 years, the lockring was still holding it well

CyclingFool95 

If you're talking about the BB cups with the dried yellow goop on them, I put anti-seize all over those. I don't know what that material is but I assume it acts like a nylok screw patch and its just a soft compound that fills the thread gaps and adds friction. Loctite 222, which is what you should probably be using if you use threadlocker, is an anerobic compound - it cures once air is removed - so, it will cure in the thread to a weak bond.

CyclingFool95 

Spoken like an engineer. Pre-load is your friend.

sdmc530

I use antiseize on:
BB, pedal threads

I use grease on everything else
I use carbon paste on seat post

I use no Loctite....some of the bolts have the blue thread locker painted on from factory but that is it.

right or wrong this is what I do.

CyclingFool95 

Glad to see I'm not the only one, although I use Park ASC-1 where you use grease.

dsbrantjr

RF and microwave engineer, actually, but there is a lot of mechanics involved.

I would strongly suggest getting a copy of this book https://www.amazon.com/Carroll-Smith.../dp/0760341036 (the prior version is just as good IMO) if you would like to really understand how bolted joints work.

CyclingFool95 

Engineers are engineers (well, except for those software guys). I'm an ME. Either those who think a certain way become engineers, or engineering school breeds a certain way of thinking. Chicken or egg. But not to hijack the thread.

Bickford's book is also very good.

https://www.amazon.com/Introduction-...67575528&psc=1

Metaluna

Seems to me the only thing you really need threadlocker for on a bicycle would be situations where the fastener can’t take very much torque, but at the same time is in an area prone to vibration or other forces that can loosen it up. There are very few places on a bicycle like this. Some that come to mind would be high/low limit screws on derailleurs, and pad clearance adjust screws on some brake calipers (e.g. the centering screws on rim and cantilever brakes, or the pad adjusters on mechanical disc calipers like the TRP Spyre). A lot of limit adjust screws do seem to come from the factory with some kind of coating on them. I’m not sure if it’s traditional threadlocker, or some kind of compound that’s just supposed to create resistance in the threads but doesn’t lose effectiveness the first time you break the bond (like threadlocker on a TRP Spyre will). I think I’ve seen some with little springs on them to keep the screw tensioned as well (like the adjustment screws on horizontal dropouts).

Here’s the thing about using proper torque (accompanied by grease or anti-seize): It doesn’t just prevent the fastener from unscrewing, but it also ensures that the two things you are joining together are joined tightly enough to prevent other unwanted effects, such as creaking, or problems caused by repeated motion between surfaces, like fretting and galling. I don’t think Loctite will save you from this if the threads aren’t sufficiently torqued. It’s more of a safety backup.