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Chordal action edition.
That purring/vibration you feel in the pedals/cranks when in your highest gears (large chainring/smallest cog)? May be chordal action.
>You will find that the position in which the chain and the sprockets engage fluctuates, and the chain vibrates along with this fluctuation. Even with the same chain, if you increase the number of teeth in the sprockets (change to larger diameter), vibration will be reduced. Decrease the number of teeth in the sprockets and vibration will increase.
>This is because there is a pitch length in chains, and they can only bend at the pitch point. In Figure 2.13, the height of engagement (the radius from the center of the sprocket) differs when the chain engages in a tangent position and when it engages in a chord.
https://www.youtube.com/@parktool/videos
Sheldon
https://sheldonbrown.com
RJ
https://www.youtube.com/@RJTheBikeGuy/videos
That purring/vibration you feel in the pedals/cranks when in your highest gears (large chainring/smallest cog)? May be chordal action.
>You will find that the position in which the chain and the sprockets engage fluctuates, and the chain vibrates along with this fluctuation. Even with the same chain, if you increase the number of teeth in the sprockets (change to larger diameter), vibration will be reduced. Decrease the number of teeth in the sprockets and vibration will increase.
>This is because there is a pitch length in chains, and they can only bend at the pitch point. In Figure 2.13, the height of engagement (the radius from the center of the sprocket) differs when the chain engages in a tangent position and when it engages in a chord.
https://www.youtube.com/@parktool/videos
Sheldon
https://sheldonbrown.com
RJ
https://www.youtube.com/@RJTheBikeGuy/videos
