Keep a close eye on the magnets, soft fuzz is no problem, when you see flakes, that means the teeth have been stressed and you don't have much time. All American Drive Service will rebuild and upgrade it for a really good price and guarantee it for 24 months. I blew mine and his price to rebuild it was less then the cost of just parts to me.

best part is ther readily available at pretty cheap . get a couple spares when people are selling cheap , rev limiter , keep engine safe . they handle more than many will admit ..