taco eater :
Christophe Jallard from Geneva, Geneva Switzerland
There is different Piaggio's housings and most of them(vario and mono) are 4 shafts helicoidal design (at least in Europe). Your input shaft is made for 2 shafts straight cut design. So your option could be a nice innovation for Piaggio 's owner.
This shaft is made to fit the 12/74 tooth (straight cut) version rear hub. I don't know about usa but you'll find these models in France and Italy at least. Switzerland use a shorter version 9/76 tooth (straight cut) and I'll not fit until you find a 74 tooth pignon.
Good news for people who has 4 hélicoïdal designed rear hub... The case is similar so you can modify it by throwing the conversion input shaft and a 74 thoot straight cut pignon.