A small diesel engine with, say 10hp, will only give you about 10hp of continuous performance. The battery will give short spurts of increased performance but your average power available will be only what the donkey engine provides minus line losses. That's one of the problems with hybrids. Great for commuting but not so good for performance.Two deep cell 12volt batteries = 60 lbs. One small diesel direct injected motor & generator = 120 lbs. One 24 volt hi-torque electric motor = 50 lbs.
Total approx. hybrid powerplant weight: 230 lbs.
Add that to a rolling chassis weight of around 180 lbs and you have a hybrid electric motorcycle that weighs around 400 lbs.
Too heavy for a dirt bike, but in the ballpark for a street machine.
BTW. Those small deep cycle batteries you see at auto supply places aren't really deep cycle. They are marine batteries and are hybrids with both deep cycle and starting features. Real deep cycle batteries are more expensive. I just bought a big 12V real deep cycle battery for my cabin, Weighs about 120lbs and costs $175.I thought this whole electric bike deal was about saving the environment, green technology and alternative fuel economy?
You want performance, forget electric. Go with steam! Yeah, steam power baby...whooo whooo....