I'm looking for a 4 season car replacement that I don't have to register or pay insurance for. I made an e-bike out of a cyclone 3000 electric motor and a few KW worth of batteries. I get about 45 miles @ 30mph average in my hilly area. But my commute is 40 miles per day and I would like to go further as a car does. I'm looking to add a gas motor into the mix to extend the mileage, I figure the electric portion can get the bike going up hills and get the bike moving quickly and work in symmetry with the gas motor to increase efficiency on both on long rides, but there are some caveats I'm uncertain about. For starters I don't want the kind of motor system that I will need to constantly maintain and tweak. I don't know much about gas motors and I don't want to be messing with it all the time. This has lead me to a GEBE 38cc motor here https://www.bikeengines.com/shop/4-stroke-bicycle-engine-38cc-silver-eagle-kit/ easy install, reliable, claimed 200mpg. Here's where it gets messy, my electric system can go at highway speeds if I so desire it to, but this motor system cannot handle those speeds I'm assuming. Of course I won't be going 60mph 99% of the time but I'd like to at least stroll about @ 40 mph when I can and go a minimum of 30mph average. This is a quote from their site. So it would appear that there is a conflict with my design requirements. Which leads me to you, hopefully you experiences folk can lend me your wisdom.