I know i'm at an old thread. But its a Nice topic & as with any odd tech- engg topic this too was bound to die fast
All i've got now is to share a pic of this vintage 2s-v2 cycle.
cheers!
Edit:
Found the link :
The Stanger Motorbike
This machine of 1920's vintage, ~600cc & shared crankcase is said not of success owing to its tech issues, which i think associates to material & manufacturing limitations of that period.