My charger and battery :(

[Lanchon]

> do not forget the aerodynamic drag that increase with approximately the square of the speed

drag (the force) increases with the square of the speed. thus, the power dissipated due to drag (which is drag force times speed) increases with the cube of the speed.

[stevo]

Andre,
Re your quote "with my 36v 500w engine, I was effectively able to 32-33 km/h without pedalling.
now on the 48v regen controler connected to the same engine... ", I assume you were/are using a 36V battery.  Does this mean you can use a 48V controller with a 36V battery?

[andre]

I'm using a 48v lifepo4 pack with a 48v regen controler, but connected for the time being on a 36v - 500w engine.
For my understanding comparing the performance of HBS36v and hbs48v engine (curves and tables are on the gm site, but there is error in 48v sheet, Pin =pout...), there should not be a hudge difference (in term of max speed)...between a 48v engine working a 36v and a 36v engine overvolted at 48v. Most probably the efficiency should be a bit lower (more heat dissipated TBC...). at least my specific electric consumption moved from 6 to 8 wh/km 36v to 12 to 16wh/km in 48v... which in my mind should be mainly due to drag (force) effect, compensating by a large increase of power to be input as quoted before. the effect of slightly lower efficiency being, I believe minor - or a secondary order of magnitude at least- compared to the effect of drag. passing from 30 to 40 km/h.....
best regards,
Andre.