107cc 4spd auto/w/elec.start cyl. & head to a 72cc clone

[proflow]

Can I swap out the cyl & head (107cc 4spd auto/w/elec.start) midi street pocket bike top end to my wifes 72cc Shucks/Oriely pit bike ?
They look the same on the top end, but I'm unsure of the rod length.

I'd just swap motors straight over but that rorary shift pattern is crap & dont need the extra weight of a starter & batt. on the little dirt bike !

Thanks in advance---Proflow