Aluminum Frame - Seatpost sticking

[abr5]

I have an aluminum Rock Lobster that is having trouble with seatposts getting stuck. I was trying to install a 3t carbon seatpost but could only get it halfway in before it getting stuck. It took a few hours and boiling water poured onto the frame to get it out. Presumably there is some corrosion in the frame that is gripping the posts and refusing to let go. What's the best way to remove this and prevent seatposts from sticking in the future? Flap wheel? Wire brush? Chemicals?

[ultraman6970]

Easy fix... grab a piece of wood or plastic. like a rod, then cut like a slit in the middle, not big... then put sand paper folded in the slit.

Then put that rod in a drill and put the thing inside, go up and down like a mad man.

You can do something similar using #0 or #1 steel wool and a rod...

when you are done put a lot of grease and put some carbon assembly paste in the seatpost. Done.

ps: remove the BB or all the cr@p will get on top of it.

[Joxster]

How far down are you going? Is it the bottle cage that is interfering with the post?

[ultraman6970]

Good call... specially if the frame is small to xs...

[abr5]

Not even close to the water bottle bolts, I'm 6' 2", no small frames here! Will try the homemade flap wheel though, seems like a good solution!

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[David Kirk]

Do you have accurate calipers to check the outside diameter of the seat post? If so measure it at the bottom, middle and top and see if it varies.

I've seen more than one frame that was reamed and honed in an effort to get a seat post to fit only to find that the post tapered and got bigger as you went up.

dave