TIL most shop owners are dead wrong about using WD-40 on bike chains

I've been working at a shop in Portland for about 8 years now and I always heard from the old timers that WD-40 was the devil for chains. They swore it stripped all the factory grease and ruined components. But I actually looked up the testing data from a guy who ran a bunch of chain wear tests on a rig. Turns out modern WD-40 Specialist line has PTFE in it and actually works fine as a cleaner and light lube if you apply it right. The real killer isn't the product, it's people spraying it on wet and never wiping off the excess. I saw a test where a chain lubed with WD-40 lasted 2500 miles before hitting 0.5% stretch which is totally acceptable for a commuter. Has anyone else actually run their own wear tests or are we all just repeating what some mechanic said in 1985?

3 comments

3 Comments

adamgreen2d ago

My chain lasted 2,000 miles on WD-40 before I forgot to wipe it and my bike made sounds like a dying seagull...

jakel362d ago

Bro WD-40 is literally a degreaser not lube lol

keith_rodriguez2d ago

That "dying seagull" sound means the chain was bone dry and grinding metal on metal. You gotta wipe off the excess WD-40 after spraying it, just leave a thin film and let it dry a bit before riding. If you do that right with the regular blue can, it'll keep things quiet for a good while.