E-max 4kW hub motor

[flexy]

I have just obtained an E-max 110s scooter with a 4000W 48V Motor

I was wondering if this motor could be run at 72V , I'm planning a Lithium upgrade from the stock SLA's

What would the best current rating of the controller?

My current 2KW scooter with 72v LiFePo4 , can draw up to 160 Amps and that's in a 10 inch hub.

This new motor is 13 inch hub so would I expect it to draw more current for the same torque and speed?

 

[ctirad]

I was wondering if this motor could be run at 72V , I'm planning a Lithium upgrade from the stock SLA's

Higher voltage is not a problem. I plan the similar mod on my friend's e-max, BTW.

What would the best current rating of the controller?

The original controller is capable of 45A and 80A (turbo button) of battery current. I think, the 18FET infineon/lyen with 4110 FETs should be adequate replacement.

My current 2KW scooter with 72v LiFePo4 , can draw up to 160 Amps and that's in a 10 inch hub.

Are you sure? These 2kW scooters are typically limited to 45-50A of battery current. Or do you mean a phase current?

This new motor is 13 inch hub so would I expect it to draw more current for the same torque and speed?

No. There is not any relation between torque, speed and the rim diameter. It's all about the contruction of the particular motor.

 

[flexy]

Are you sure? These 2kW scooters are typically limited to 45-50A of battery current. Or do you mean a phase current?

That's max current measured on Cycle Analyst when accelerating up steep 33% hills, It can also generate 60 amps under hard regen braking.
I'm using an ecrazyman 18 FET controller with shunt mod, max current set to 80 Amps.

Are you bypassing the dash computer on your friends emax? It looks like this might interface directly with the stock controller.

I want to replace the controller with something more powerful, but I feel the 18 FET is reaching it's limit on the smaller scooter even though performance is excellent.

 

[whereswally606]

I have one of these sat in my garage. plan someday to build a hybrid tadpole road legal trike with it. Anyway blew my old magic pie controller testing it. think i may have accidentally shorted a phase wire, take home message is be careful. annoyingly I did have it working but never caught any video of the fact.

Regards Andy

by one of these i mean the motor not the whole scooter though that would have been smarter. still i got it cheap.