Originally Posted by luke.harrison
as I said to each his own, but when I installed my tapered RaceFace cranks the instructions clearly indicate "grease the BB axle tapered surfaces", their not alone. A buddy of mine who is a mech engineer told me it cant hurt, there's no way you'd deform the alu with a bolt that small... its only repeated crank pulling that deforms the hole..
You are not deforming the hole, you are expanding it. The taper acts as a wedge against the softer aluminum and lubrication accelerates this. BTW, I'm an ME as well; really, don't grease the taper.
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