Originally Posted by
sweeks
Then there's titanium frame with a titanium post. No galvanic reaction there, but titanium is said to be able to "cold weld" itself to itself. I've used a copper-based grease and haven't had any problems in almost 20 years.
Copper based grease is the best solution for never worrying. Back in 98 or so the local Dicks sporting goods had a Ti mongoose road bike with full ultegra that was clearanced for nothing since the ti seatpost wouldn't move. Wasn't greased on assembly and bonded to the frame.
Aluminum is less so likely to bond but there is a reason ti spokes ship with a little copper grease for use with aluminum nipples. Haven't heard of steel being an issue but as with anything, just grease it.