Gregory Bender

Brake cable-to-lever angle

Moto Guzzi V700, V7 Special, Ambassador, 850 GT, 850 GT California, Eldorado, and 850 California Police models

Updated:

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I extracted this recommendation from Ralf Brinkmann off of the Yahoo! Loopframe_Guzzi news group. In Ralf's own words:

I found an interesting photo of a 2 LS front brake - sorry for recycling it for my drawing.

My theory in short words:

  1. The ideal angle between brake lever and the pulled brake cable is 90°. The more this angle differs from 90° the shorter the resulting length of the brake lever will be and so the resulting torque.
    I assume less than 60° for the angle in the picture when the brake is pulled. The effective length of the lever arm in the example results in less then 86 percent of the real length approximately.
    Moto Guzzi drum brake cable to lever relationship. Effective lever length = real lever length × sin(angle).

    Moto Guzzi drum brake cable to lever relationship. Effective lever length = real lever length × sin(angle).

    Photo courtesy of Ralf Brinkmann.

  2. The eyes in the connecting rod should have nearly the same distance from center to center as the cam shafts of a 2 LS or 4 LS brake.