The problem is that the wheel has become misaligned with the frame so the top is close to the frame and the bottom is pushed out from the frame and hits the footman and rocker arm.
The solution is to loosen the bolt that holds the wheel to the frame, hold the wheel even with the frame so it does not touch the footman, and tighten the bolt. This bolt needs to be very tight or the wheel will wobble and damage the washer.
For the gear-heads we tighten to 110 inch-pounds. That would be pulling 30 pounds on a 4 inch wrench.
The bolt may not tighten because
the axle is turning with the bolt. To solve
this, take the bolt out, put a drop of oil on
the threads near the end and then thread the
bolt back in and tighten it.
How to fix a rocker rubbing on the wheel.