Don get a rack on your ebike and strap a gallon of premix, at convenient stops along ur ride gently remove cap and breathe deeply. Then close cap and ride on. Also mount a mikuni carb somewhere so as to adjust the virtual mixture. That should suffice !
My commensal meta power 650 Enduro mountain bike with the e8000 Shimano motor is coming this week. Im getting the aftermarket chip to keep the engine from cutting out at 20 mph. It's all proven technology. Not a hub mounted motor. U gotta ride an ebike that has the center of gravity correct. There is no pothole big enough that this bike can't survive. And remember I love all my mopeds but electric motors are the answer to moped reliability issues. And the Kickstarter mopeds pale in comparison to what's out there. Even KTM is making e mountain bikes. Im unconvinced if electric cars make much sense but two wheels do.