Aluminum alloys also oxidize..
Originally Posted by robgod
My seat stem has seized solid and I'm not able to budge it. Its an aluminium frame (at least I think it is) and an aluminium anodized stem so I don't think they could have rusted.
Anyone know of any tricks or techniques to free it up?
Originally Posted by unterhausen
I heat the seat post with a plumbing torch. You usually don't have to get it very hot at all. Always worked for me. For some reason people hate this idea and refuse to try it in preference for hacksaws and other techniques that are dangerous for the frame.
Aluminum corrodes, this is probably what has happened with your seat post.
Before you go with heat, try some ammonia sprayed
at the juncture of post and frame, and if you can get it
also dribbled up into the joint from the bottom (requires
pulling the BB), that will also help.
Ammonia works on aluminum alloy corrosion and you might
get lucky. The preventative measure in future is an anti
seize compound in the frame tube and on the seatpost.