Found out that bike chains from the 1970s lasted half as long as modern ones

I was reading through an old Sheldon Brown article last night, and he mentioned that chains from the 70s used to wear out around 1,500 miles. I was surprised because these days I get closer to 3,000 miles out of a decent chain on my commuter. The steel back then was just softer, I guess. Made me appreciate how much better the metallurgy is now, even on cheap chains. Has anyone else run into old parts that wore out way faster than you expected?

3 comments

3 Comments

alicemurphy4d ago

Tbh I read somewhere that old bike chains were actually made with a different type of steel that was softer but cheaper to produce. There's a guy on YouTube who tested a NOS 1970s chain against a modern basic one and the difference was wild. The old one stretched way faster and the pins wore down way sooner. Honestly it makes sense since back then they weren't making chains to last thousands of miles. They probably figured most people would just replace the whole drivetrain every couple years anyway.

ryanm604d ago

Wait, has nobody mentioned the roller width difference? I measured a 70s chain against a modern KMC once and the old one was noticeably wider between the inner plates. That extra slop means it wears out way faster because the rollers can rock side to side under load. Plus the old pins had no chamfering on the ends, so they basically acted like tiny files against the sprockets. Modern chains have those chamfered edges specifically to reduce that friction point.

dylan_brown304d ago

Did your friend end up trashing an old bike project because of that chain slop issue?