I built this motor on rock n roll...
New bearings, seals, sandblasted the head, clutch cover and made everything nice. This motor had an output bearing that was totally shot. Took me a little while to do but I did it right.
Lots of pipes as easy to mod for this bike. The proma was the most used pipe I've seen but I'd probably up to a blaster pipe or something..I will be resurecting the malossi kits with a little better piston setup. For 50cc's those things probably are more powerful and more efficient than the polini.
Apparently I'm the only guy who rebuilds these things...glad I got lots of parts for em.
For 300, I can believe you havent found a buyer, this thing is pretty and if it runs it probably runs pretty decent. With a bigger intake/carb and a pipe, some mild porting...reliable decent ped..puch 3 shoe for the hills.
Good luck with the sale, sorry to ruin your thread with this nonsense talk Rob and I are having.