A chat with a frame builder changed how I see chainline

I was at the local bike show last month and got talking to a custom frame builder from Eugene. He asked me how I check chainline on a customer's bike, and I gave my usual answer about the center of the chainring to the bike's center. He just smiled and said, 'I worry more about the chain's path to the center of the cassette under load, not just a static line.' That really hit different because it made me think about chain wear and shifting under power, not just alignment. I've started paying more attention to how a chain sits on the middle cogs when the rider is putting down force. Has anyone else had a moment that changed a basic check like this for them?

3 comments

3 Comments

luna_craig5810d ago

My old shop foreman in Portland said the same thing about loaded chainline. He'd have us check it with a rider actually pedaling on the stand. It makes a huge difference for chain life.

walker.hayden1mo ago

That Eugene builder's point about load is a real eye opener.

cole_patel4129d ago

Honestly that Eugene guy sounds like he's overthinking it. I've built up dozens of bikes just using the static line check and they shift perfect under load. @walker.hayden maybe it's just a custom builder thing for super picky clients.