SCochiller

I see some manufacturers call for grease, others for Loctite.

My gut says to use grease and routinely check the tension. Your experience?

IRideTiBikes

Trust your gut on this one.

531Aussie

Yeah, I'm a grease guy (marine), but I'm always changing stuff, so it never gets a chance to wash out and expose the threads to possible corrosion and seizing. Loctite, or something similar, is probably better for people who ride a bit in the rain and never change stuff in, like, 'many' years.

I was once working on a friends mountain bike, and it was the most-trashed thing I've ever touched. The chain was rusted a fair bit, and so worn that the rollers were almost hanging off the pins like loose earrings, and the chainrings were so worn that the teeth looked like baby kitten teeth (small and pointy ). The derailleur was so knackered that it barely moved and didn't keep the chain tensioned at all. The cables were stuffed, the bb axle was worn and wobbling, etc, etc.

Anyway, I went over one day to change the BB and a few other bits, and expected the bottom bracket to be seized in the frame and impossible to remove. However, I brought a 'torque pipe' with my tools, just in case there was hope. Well, the BB came out quite easily, because they had had some sort of cream-coloured thread lock applied. The threads on the BB and the frame were so pristine I couldn't believe it. OH HAIL TO THREAD LOCK (in certain situations). The whole bike had been trashed for about 20 years, and there were these brand new and clean threads!! Ya hadta be there.,

ericm979

Grease, and use a torque wrench to set the correct torque.

mazdaspeed

Grease and mild (blue) thread locker have overlapping purposes in many instances, that is, discouraging galvanic and other types corrosion that get fasteners stuck. The difference obviously is that loctite helps prevent things from coming loose on their own but it only requires slightly more effort than normal to remove. Once it hardens it seems to hold up better than grease which can sometimes degrade or get washed out before it should. Obviously loctite shouldn't be considered a lubricant but there are few things that have threads that you could mess up by using it, so if you have something like Italian BB shells or bolts that are prone to loosening it makes more sense to use it than grease.

mazdaspeed

And by pinch bolts I'm assuming you mean a hollowtech 2 crankset, in which case either grease or loctite should work fine as those two bolts don't seem prone to loosening once they're torqued, and the plastic tensioner helps keep the cranks in place too.

kraftwerk 

Grease and Loctite have two very different functions. The manufacturer should say what is required. Be aware there are different grades of grease and different grades of Loctite or Permatex which is about the same thing though a different brand. (note: There is also a third thing which is anti-seize compound, something else entirely, which has a high copper content it is good for keeping things from locking up/ 'freezing' over time, I use a lot of this on my cars lug nuts.)
To simplify you might find 4 types of Loctite in well stocked hardware store...lucky you, and you should learn about the red the blue the green and the purple, as they all do different things. For instance the purple is number 222 (and I can't find it anywhere for $ 9.99 but many places have it for 17.50... rip) But the purple is what is required for installing 2011 11 speed Campagnolo Super Record crank arm-cups, or so says the users manual. Purple, being the least "adhesive" of the four acts less like a "glue" and more like an anti-seize compound. Really I am guessing a bit here but the users guide does get sexy with this type of language: "Loctite 222 is anaerobic, only solidifies in the absence of oxygen, there for it should fill the threads completely." You must use it correctly. You want to be able to remove those cups again someday (when you upgrade to 12 speed! ) Take the science seriously. "Gut feeling" is for when you meet a girl in a bar...there is no science for that...just condoms, unless she is on the pill, then that is ALL science.... I digress.