Why I'll never skip checking chainline on a new build again

I built a new road bike last month and the gears kept jumping when I pedaled hard. I messed with the derailleur a lot but it didn't help. Then I thought to check the chainline and it was way off. After I fixed that, the shifting was smooth. Anyone who doesn't check chainline first is wasting their time.

3 comments

3 Comments

the_eric1mo ago

Many times, tweaking the derailleur fixes shifting without ever looking at chainline.

hunt.sage1mo ago

Under heavy pedaling, frame flex can throw off your indexing without touching the derailleur.

susanm561mo ago

Reminds me of how we often fix the symptom... not the real problem.

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