If a given crankset has a chainline specification and that specification is implemented exactly, would that then result in the cranks being centered?
The pictures show the distance between the inside of the crankarm and the outside of the chainstay on each side. Should these measurements be the same?
by Zagato36
5 Comments
No.
Don’t assume the frame is symmetrical. Take your measurements off the centerline of the rim of a trued and dished wheel with no tire on it.
Probablemente el eje de las palancas sea un poco largo en relacion a los mlimetros de la caja
Centerline depends on the cassette on the rear wheel, than you look up where the crank needs to be, at least that’s how I do it.
I just watched a bike fit short on this topic
https://youtube.com/shorts/SIUZYfap75E?si=cFd1YAt_t4yQHbRd
Here is how I would go about it. Thank you for the positive learning experience.
1) Start with a perfect rear wheel and a straight frame.
2) Establish the chainline per crank spec or through experience.
3) Install driveside crank arm.
4) Install non-drive side arm to mirror driveside so both arms mirror each other.
5) Measure Q Factor.
6) Remove non-drive side arm and adjust spacing as needed to meet Q factor measurement.
7) Install non-drive arm in the correct fashion.
8) Go for a ride.