Ecells Super Monarch 1500 rear motor problem

[gbcarl]

I have the Ecells 1500 Super Monarch, it has two Bafang 750w motors... this thing is a tank, I realize that, weighs 95lbs, I add 160lbs. If i just use the front motor, full throttle no pedaling, it will climb to about 27 mph. On rear wheel only, it feels like its “chugging” and slowly get to 22mph, but any incline it drops, and doesn’t feel like it has much power. Am i wrong in thinking that. 750w motor is strong enough and should be able to push this bike a little easier? If I get it up to 27mph on the front wheel, and I switch to rear wheel, should it then at least be able to hold that speed or close to it? This rear motor feels very weak on its own. I understand their might be some differences between pulling, vs pushing etc, but that much?
(2 batts 52v 14ah, 52v 17.5ah)

 

[amberwolf]

It's likely that both motors, controllers, and batteries are identical to simplify manufacturing. This is good news in that it means you can probably swap parts to verify which one is causing the problem.

THe first thing to swap is the batteries. If the rear battery is unbalanced or otherwise unable to provide full power to the rear motor, then it could cause problems when under load. (if both motors behave normally and identically when the bike is upside down, then this could be the problem).


If that doesnt' change anything, then check all the wiring on the rear system from motor to controller. The other thing that usually causes what you describe is a hall sensor wiring fault, or a phase wire connection problem. The most common place either of these happens is at the axle exit from the motor, where the wiring comes out of the end or side of the axle, and it usually happens because of a crash or the bike falling over. The next most common place is the connectors from motor to controller.