Technical FAQ: Autoshifting

  • By Lennard Zinn
  • Published Aug. 18, 2009
  • Updated Nov. 4, 2009 at 8:41 PM EDT

Originally published: Aug. 18, 2009

Another solution: One other solution to Dan’s “auto shift” problem:

I had the same thing happen to me on my Rivendell Rambouillet with indexed downtube shifters. Turns out, grit had accumulated under the bottom bracket and was causing friction between the cables and the bottom bracket.

When I stood on hills, the extra torque makes the bottom bracket sway back and forth.

All is OK if the cable was able to slide as normal, but with the fact that I was in first gear so the derailleur couldn’t move to the left, the friction made it so that the cable eventually caught enough that it pulled the derailleur just far enough to the right that it would drop a gear.

Very frustrating, but after brushing the bottom bracket clean and squirting some oil on it, all was better.


FILED UNDER: Bikes and Tech / Technical FAQ TAGS: / / / / /

Lennard Zinn

Lennard Zinn

Our longtime technical writer joined VeloNews in 1987. He is also a framebuilder, a former U.S. National Team rider, and author of many bicycle books, including Zinn and the Art of Mountain Bike Maintenance and Zinn and the Art of Road Bike Maintenance, as well as Zinn and the Art of Triathlon Bikes and Zinn's Cycling Primer: Maintenance Tips and Skill Building for Cyclists. He holds a Bachelor’s degree in physics from Colorado College. Readers can send brief technical questions to Ask LZ.

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