A customer in Tucson taught me a trick for stuck seatposts I still use

This older guy came into the shop with a steel frame bike, the seatpost was totally seized. He said he'd tried everything for months. Instead of more force, he told me to mix equal parts automatic transmission fluid and acetone, then let it soak for 48 hours. We did exactly that, and after two days it twisted right out with barely any effort. I'd never heard of that mix before, but it's saved me a bunch of times since. Has anyone else got a go-to homemade penetrating oil recipe they swear by?

2 comments

2 Comments

blair_davis501mo ago

Ever think heat was the only answer for a stuck seatpost? I used to reach for the torch first every time. That ATF and acetone trick is a total game changer, way less risky than cooking the frame.

ross.william1mo ago

Remember when we all thought melting the frame was just part of the process? I warped a perfectly good seat tube once because I got a little too excited with the propane.