BRN 40.3mm 50cc cast iron kit for minarelli V1 piston port.
no piston with this one, but here is the closest one we have that will work right now -
50cc am6 piston
4 ports
these kits seem to have a casting flaw. they all have the exact same chip in the cylinder. you can see it in the photos. should still work fine, that's why this one is cheaper. so be aware of that if you buy this.