Steve and Terry,
There is no telling how long the bits of magnetic metal were in the pan. The PO’s kid may have been a little hard on the bike when he was learning to ride. Like you suggested, they are likely from the tranny and starter clutch. I’ll tackle that inspection next. Since I am just learning about this engine, it seems to take me three times as long to do the work as it should. For instance, it took me from 7 PM until 9:30 PM last night to check the valve clearances and adjust the cam chain… that includes clean up of my mess. At this rate, I’ll never be on the road.