Yellow anti-rotation washer, Shimano Nexus 3 speed with trailer? Should I keep or remove the yellow anti-rotation washer when installing a child trailer to my e-bike (EcoRide with Shimano Nexus 3 speed)? The trailer installs through the wheel axle (see attached img.) ![Shimano nexus with trailer mounted through wheel axle](

If the wellow washer is a anti-rotation washer - one that fits in a slotted dropout and prevents the internally geared hub from rotating with the axle - then yes it needs to be in place.