Robert..
breaking traction?
to make a guess what you'll need take your weight (yes.. how big's your butt
)
and the weight of the vehicle when it's done (batteries are heavy)
have that?
perfect, convert to kilograms.
nice.. now multiply that by 6.867 ( short for 9.81 * 0.7)
Now you know the "sticking" force of your four wheels to the road.
(Newton)
example:
260 kg * 9.81 m/s² * 0.7 = 1785.42 Newton
to break traction the motor needs to provide MORE than that force,
and must be capable of applying that force instantly (the even tougher part)
otherwise you'll transform the power into forward momentum
but let's assume you lock the front brakes (cheating.. I know)
then 1800 Newton should do the trick already
How big are your wheels? or precisely what's the distance between the road and the center of the driven axle?
(for a 18" wheel we can assume something around 22 cm, but measuring it will provide more accurate results)
1800N * 0.22 m = 396Nm of torque;
that's what you need to break traction in our example (260kg driver&vehicle unit, 18" wheels)
that's a lot.
with a 6:1 drive ratio your motor will still need to provide a torque of 66 Nm
(four to five times the torque a typical 212 predator provides)
if you don't want to spend a fortune for that thing...
(roughly a 9kW motor would be needed for a dry asphalt road)
you'd better find loose gravel or a wet road to spin tyres...
best: find a patch of ice next winter
'sid
