Anyone got any ballpark figures for what kind of torque a starter motor produces on a healthy battery? Or a handy link would do.

Obviously some are bigger than others but just loosly trying to figure out gear ratios (and associated component positioning) for electric reverse.
jk

not sure on torque but the on in our diesel off roader is 2200 watts or about 3 horse power ish

interesting experiment for you to try it is ot remove the spark plugs and see how fast the car will move in 1st gear on just the starter motor.

that wold give you an idea of gearing.

for reverse gear, you would be better of with a slow speed for more controll rather than shooting off backwards at a billion miles per hour!

Well i had one fitted 1200watts.

90teeth had the ring 11teeth the motor had.

7km/h max on reverse.
3.92diff, 500kg car weight. approx.

I used a controller for it to manage the speed (PWM) best bet to do it is to change the wires of the motor (so that it has 2 wires instead of one)


Tks

Cheers, good ideas.

Any idea where I could get a really small gear cut? I guess around 3 to 4" dia as I'll be fitting it to and driving the R1 OP sprocket, using the chain drive for the final reduction ratio. Makes mounting everything easier too.
jk