Showerthought: I quit greasing saddle rails and I'm not going back
For years I put a dab of grease on every saddle rail bolt out of habit, until a customer's carbon railed saddle started creaking and sliding at 4 Nm. Now I clean them dry with isopropyl and torque to spec, and the creak on that bike in Louisville stopped for good. Any of you run into rails slipping because of grease, or am I the only one who did that for too long?
A dry carbon rail at 4 Nm is basically a friction grip, so yeah, it holds, but it also means every micro shift in the clamp is grinding grit into the rail finish instead of sliding on a film. I've pulled saddle clamps off bikes that ran dry for two seasons and found the rails chewed up right at the clamp edge, and the bolts were half seized from road spray getting in. A thin smear of grease on the bolt threads and under the clamp head isn't the same thing as slathering the rail surface, and that's where people go wrong. Bet that Louisville bike would've creaked again the first time the owner hit a wet winter if the hardware wasn't protected.