This is what I did at Phillip Island.

This is the gear cluster from the PX. You can see that there are three teeth broken off. The other gears worked OK, but the broken teeth were rattling around inside and making a hideous racket. The wear on the gear at the top (first gear) is apparently from using the kick start, which I was using most of the time. Now I have the correct battery with the right number of cold cranking amps, so the electric start has been reliable again.