Originally Posted by
Slaninar
This is incorrect. Lubricant will allow a proper crank to axle engagement using appropriate bolt torque. It will not help overtightening. I mean - you can overtighten and strip bolts if not paying attention, of course, but having a crank to axle interface lubed won't make any difference there.
Maybe I wasn't clear about what is being overtightened. I'm talking about the taper fit, not the bolt or nut. IOW, pushing the crank too far onto the taper.
A lubricated bolt will gall and seize up if not lubricated and overtorqued. So yes, always anti-seize your bolts. But you'll almost certainly either bottom out the crankarm or the bolt itself, or crack the crankarm before you strip the threads on a crank axle, bolt, or nut from overtightening it. I'm sure it's happened, not that I've tried.
Originally Posted by
Slaninar
Torquing it without lube on the interface, on the other hand, does cause problems, as was nicely explained in the link from Sheldon Brown's site.
Jobst Brandt had lots of opinions, the most important one being that he was always right.
In this case, as I was implying before, it's not about right or wrong. It's about tradeoffs. When manufacturers and bicycle service institutes make recommendations, I think it's fair to say they've weighed the options and done their testing, engineering, and reverse-engineering, and don't make those recommendations because someone BITD told them that's how it's done. Their collective experience is considerable, and well earned.