Here are some photos of the flywheel scrapping marks ,just like it was put in a lathe.
I think fleetwin may have the answer for this wear ,a wobbly pulley. The distance from the center of the flywheel to the wear mark is the same distance on the pully from the center to the edge of the pulley. The wear marks are right outside the bits red tape
"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson