syncronizing two ht's might take an engineering degree.
are you sure gearing the thing up wouldn't be more fun (& useable)? but maybe you've done that...
If this guy starts making engines for sale,I want to know about it....Would love to see a new generation of affordable quality engines(if they will be afordable....On this site JDM PUNK Acme engines a company in Ohio is making a V-Twin-paring at the moment two 50cc engines---but he is actually going to pour engine castings and make 1 engine he has a running prototype .