Mattyman999

I’ve finally managed to remove a very stuck dropper post from my carbon Whyte frame this evening. It took many days of being soaked in ACF-50 put in from the BB and a lot of patience. Now that I have removed the seat post; I have ordered a new dropper, however the seat tube really needs to be cleaned out as I think there will be a lot of corrosion in there. Has anybody got any tips for this please?

Mad Honk 

Matty,
If the tube is round use a wire brush wheel on a drill to clean any bits from the tube. They make them in nominal sizes from 1/4" to 1", available at a hardware store. Be sure to wash it our with a bit of solvent on a cloth and pushed down the tube with a long dowel to the bottom bracket. Do this before re-installing the bottom bracket so you can get all of the bits out of the tube. Smiles, MH

Russ Roth

Being carbon, I wouldn't go shoving any wire brush down it, I'd look for a bristle brush like a bottle cleaner. Personally I'd clip the handle off and use it with a drill to make it easier.

Andrew R Stewart 

Know that most any solvent you can buy at the LHS (or DYI) won't harm the carbon, can't say the same for any paint or decals on that carbon though.

I use a flapper to clean up tube interiors. With the steel stuff I hobby with I use 80 grit cloth. For carbon I might consider 180 or finer grit. Remember it's often not so much the tool as how it's applied that counts. A flapper is a strip of abrasive cloth slid into a slot cut into the end of a rod. The other end of the rod is powered in a drill. With fine grit, slow speed and short "cleaning" time the amount actually removed will be very little.

Carbon doesn't corrode in the since that we see metals doing. I would suggest a thorough cleaning with a solvent and test fitting a post before doing anything more. And use carbon paste or anti seize on assembly with the replacement post. Andy (who wonders about the other aspects of this bike that might also show exposure/age issues)