[leew]

Been giving it a bit more thought and now thinking about using an electric drive rather than an ICE. Main reason being noise, I want a quiet ride and most small bike engines seem very noisy, there is also vibration from small ICE engines, especially single cylinder engines known as "thumpers". There is also the issue of heat, ICE needing more cooling than an electric drive and possible damage to the CFRP body.
While electric brings it's own problems, main one being range, also the cost of the components is much more than getting a bike ICE engine from a junk yard. I think the extra cost will be worth it though. I'm thinking of a 5Kwh LiFePo4 pack now, it won't be cheap!. I am hoping for 100 mile real-world usable range.
Another reason I like the idea of electric is packaging, I was having trouble fitting an ICE lump in my proposed design whereas an electric motor is smaller and the battery cells can be placed more easily than an ICE lump.