To avoid chain rub on the inside of my derailleur when in the smallest chainring and in the biggest cog on the cassette I've turned the L-screw out / counter clockwise. Now the rub is gone but due to the angle the cable is pulling the front derailleur it is nearly impossible to get into the largest chainring.
Turning the L-screw in a bit more pivots the derailleur into a more horizontal position so that the force of the pulling gear cable is no longer towards the derailleur's center of rotation and thus can actually move the derailleur.
To fix this I'd probably need to either get the cable to pull from a position closer to
A or at least to somehow generate some force towards
The other solution would be to turn the L-screw in again and avoid the chain rub in a different way.
How do I do that?
- I've already tried to move the derailleur on its braze-on mount.
- I also turned the small chainring around so that the numbers imprinted are facing the outside.
- I'm sure it's not about friction in the cables. Shifting works fine in both direction if the L-screw is further in.
- The manual mentions that the little pin around which the gear cable is lead can be rotated by 180°. I've tried both positions, the left one improves the issue slightly.
Bike is a Cannondale Synapse Women's (Cann-S2), 9-Speed R3000 Shimano Sora, front derailleur: braze-on type.
The green line is the gear cable.