DC controller for geared motor to give Max Amp cushion


100 W
Jan 21, 2020
People do this all the time, right?

I'm having a problem with a KT 22A 36/48V controller --- power weakens and then cuts out up hills, even in PAS 4 which I'm guessing is only around 400W, maybe 550W max. Geared motor is rated 450W, max somewhere between 750-1000W. So this really 'should not' be happening, but it is. Outside temp was under 80F. Looked at the controller and wires, they look brand-new after 100 miles on them. No melting, no black spots. So it's probably the controller. I know there is a huge KT fan base here but this is the 3rd KT controller to start dying on me; the other two were OK for about 2000 miles each. And it's not like I'm maxing out the watts every time I ride. I rarely do that if I can help it.

I've been running an EBikeling 30A 1200W controller on another geared motor bike for over 1000 miles and besides the PAS really sucking, the throttle is great and there has been absolutely zero problems with it. It has NEVER cut out in 1000+ miles. Zero times. Unfortunately that particular controller make has been discontinued. Because I'm going to do throttle only for this 1st bike as well, I don't really need any fancy controller/display. I need something that works and can handle some heat. Yes, sorry everyone, but the KT IS NOT DOING THE JOB! 30A capacity for a 450-500W geared motor seems like the correct choice. Just go up in amp capacity with a more heavy-duty controller = problem most likely solved. So why do they make lower-duty controllers in the first place that only have 10-20A max capacities? The price difference is not that large. Maybe because they can't fit a longer controller in the frame's triangle or something?

What is your opinion --- do I just have a 'bad' KT controller, and try to stick with that setup with a 26-30A new KT one, or just say screw it, ditch that setup entirely and get a non-KT that's 30A with a different display and throttle? How many more times am I supposed to 'trust' a KT and wind up with something that can't handle even 850W when it's rated over 1000W? Will a KT 'almost' for sure work if it's 30A compared with a non-KT 30A controller? Same chance of working? So it's just a question of upping the amp capacity regardless of the controller?
Did a motor / controller stress test up a few steep paved hills, did not exceed more than around 500W just to test. Motor barely warm. Controller warmer. It's the controller. Unfortunately I can't find my portable phone charger with USB ports, will buy another one and a mini fan, air that sucker out in the triangle bag. The Hailong battery does come with a USB port but that and the cord will stick out too much for pedaling so I'll put the external battery and mini fan together in the triangle bag. One big happy family inside there, will unzip it as much as possible for some air exchange.

Bought a 30A 1500W controller and SW900 display to later replace this controller / display setup. The SW900 reads watts; this KT LCD5 does not. My LCD3 in the garage is toast, just checked it this morning. With the SW900 I need that to make sure I'm not going over the target watts just in case. The KT controllers and throttles tend to shoot up the watts towards max a lot. UART / SW900 stuff doesn't do that.
Found my external battery :)
Just need $10 mini fan coming tomorrow. Happy camper.