BSA B31 lightened flywheels.
GM Speedway 163mm conrod
Needle roller big end bearing
Bolted up timing side mainshaft
Jawa 895 aluminium barrel
Jawa 895 DOHC 4V head
35/30mm valves. 2 off each
40mm Delorto pump jet carb
Bore/Stroke 90.5 X 88
Comp ratio 10.5 to 1 but variable
Pazon electronic/Total loss battery
Possibly 94mm piston in future.
Possibly modified M20 94mm crank in future. 94 X 94 = 652cc
Engine HP/rpm Who knows? 50+/7500 or more ?
Torque The more the merrier!
Why not? Have you seen it done before?