Originally Posted by
Loose Chain
What is the advantage or disadvantage of routing the shift cable amlong the TT and then down a seat stay vs along the down tube and wheel stay? Seems the down tube routing would be preferred but I see older bikes with the diamond frame tend to run along the top tube.
It's preferable to run along the top so that the cable meets the axle perpendicular to the dropouts. This minimizes shifting errors if the wheel moves or is moved in the horizontal dropouts. If you run along the downtube/chainstays, any axle movement will require readjustment of any of the following, fulcrum clamp, cable stops and indicator chain.