Hi iperov and all
Well there are many motors (like HBS 1000w standard style ) that do 470 RPM FREEWHEEL at 48v (so I think it is not high speed but a standard)
but 1000w or that can draw 37 Amps well we will see! (i have yet to see it do it ) now that (MonkeyMagic) has just started testing cruise controller Mod ,,,,i think on a Pie !
changing 1 off SMD 220 Ohm change !(that is the smallest mod from standard I have seen )(this may bring the cruise controller into a new life and needed a thinking Frenchman to do this posting)
The HBS 12 is just over 600 RPM FREEWHEEL at 48v and a max Amps about 16A at 36v (not yet checked it at 48v )so 37A thats over double ....as the faster you go wind resistance you have to pay with something so it get to balancing point AIR RESISTANCE AND WEIGHT,,,, AGAINST POWER
Slower speed less resistance that seems why smaller power motors will find the balance at lower speed with less power .
(even high and low air pressure will effect ,,,,low will seem like having to push is way though and high will seem like you just lost 60 Kgs of the bike )