Because I don't want to.If one were to use gas, why not directly use it to power the bike? I can carry up to 4 liters
on my belt-drive gas bike with a range of 65 miles to a liter, 40cc engine mushing at 3300 rpm, 15 mph PAS
top spd 33 mph. pedaling like mad. (that´s without a trailer.)
On the trip last week I was pretty much the sag wagon. I carried the heavy loads for the second rider. The second rider carried a water bottle, a sleeping bag and a matt. The range on the second bike was not a good as mine and it help equalize the two bikes a bit. One big rig like mine could haul the generator and charge 4-5 bikes up over a break and allow riders with morel limited battery to participate in more remote adventures. That is what I see a generator useful for. In that case the riders would also be packing more.
Second bike