Programming Controller

[CamelP]

Hello,

I've run into an issue after installing my new display, specifically KT-LCD8HU.

While my bike is trying to maintain / not go over the top speed, the motor will consistently cut in and out every other second or so, which I think is pretty normal except you can physically feel it to the point where it makes the riding experience incredibly unpleasent, this wasn't an issue with my old KT-LCD8S display, unfortunately I am unable to see which settings my old display has so I can't directly copy them.

I'm hoping someone here has an idea how to make the riding experience more pleasent / smooth.

Bike specs:
Bafang RM G060 500 D
KT48ZWSRD-BSKI2L, 20A controller
Tyre size: 20x4.0
Gear reduction ratio: 5:1
Magnetic poles: 6

 

[Slaphappygamer]

Your C14 is set to 3. That's the strongest assist. Try 1 (weakest), or 2. I had a similar experience, but I forgot what I did to resolve that. I tried many things. Also, you might want to change the P3 setting from 0 to 1. 0 is "speed control" mode. 1 is "imitation torque control".

 

[CamelP]

Your C14 is set to 3. That's the strongest assist. Try 1 (weakest), or 2. I had a similar experience, but I forgot what I did to resolve that. I tried many things. Also, set P5 to 1. That is "imitation torque" enabled, as opposed to speed based.

Hey thanks.

I've tried both things you suggest without success, unfortunately.

I've also tried changing C5 to 3, which makes it a little less noticable, but also makes the bike incredibly horrible at climbing hills.

 

[Slaphappygamer]

C5 at 3 limits the controller to half it's max. You might want to try a different setting. Perhaps 10 will work for you? That will give you 1000 watts. Do you need the manual? I only ask, because not everyone can find it.

 

[CamelP]

C5 at 3 limits the controller to half it's max. You might want to try a different setting. Perhaps 10 will work for you? That will give you 1000 watts. Do you need the manual? I only ask, because not everyone can find it.

I already have the manual, but thanks! Setting it to 10 makes it worse, I'm pretty sure the issue is that when the bike hits full speed the bike drops the amount of watts it outputs, but the drop is too steep rather than gradually doing it and gradually increasing the watts again when the bike is about to lose speed, and I have no idea how to change that.

Incredibly weird, especially because KT-LCD8 and KT-LCD8HU are practically identical displays.

 

[Slaphappygamer]

Oh, worse is not good. Let's set that one back. Bummer you weren't able to retrieve your old settings. It took me a while to dial in the settings for my setup. I wish I could remember what I did, but I made so many changes at once.

Maybe @PCeBiker or @harryS can chime in with other ideas.

 

[CamelP]

Quick update, I’ve found that changing the wheel size to 24” eliminates the “stutter” but the speedometer is now faster by 2 km/h compared to my GPS speedometor

Anyway to get the speedometer more accurate while maintaining a wheel size of 24”?

 

[PCeBiker]

Try setting C5 to 00
That is three level slow start, but it may not make any difference if you are already moving along at speed?
I didn't hook up my PAS sensor so it doesn't work for me.

Try setting C4 =4 then turn it down to 20%

That's what I did as well as turning my power down to half with C5=3

The first throttle gear is 20% of the maximum power (which is 12.5 amps with my 25 amp controller set to half power)

The other throttle gears will be proportionally more, with throttle gear 5 being 100% power (12.5 amps in my case.)

 

[PCeBiker]

Quick update, I’ve found that changing the wheel size to 24” eliminates the “stutter” but the speedometer is now faster by 2 km/h compared to my GPS speedometor

Anyway to get the speedometer more accurate while maintaining a wheel size of 24”?

You posted while I was typing,..

So, if your ebike is how you like it now, you can adjust your speedometer reading by adjusting P1

P1=87 works for my wheel size.

 

[CamelP]

You posted while I was typing,..

So, if your ebike is how you like it now, you can adjust your speedometer reading by adjusting P1

View attachment 170407


P1=87 works for my wheel size.

I tried decreasing the P1, the speedometer got more accurate, but the stutter returned, so freaking weird.

 

[PCeBiker]

I tried decreasing the P1, the speedometer got more accurate, but the stutter returned, so freaking weird.

Yeah, that is weird.
I didn't have that problem.
I don't know what's going on?

I just recently set P2=0 but I haven't riden the bike yet.

That disables the speed sensor input so my bike apparently goes faster now.

Maybe try that, then your bike won't be trying to hold your speed steady? Maybe?

 

[CamelP]

Further inspection, the motor does not stutter when using the throttle, so maybe its something to do with the PAS settings

 

[PCeBiker]

Well, there's lots of adjustment for the PAS sensor input,..

I didn't hook up my PAS sensor, so I didn't set that up.

I wouldn't think that those settings would make it stutter though?
They should only affect the amount of crank rotation it takes and the direction before the motor starts

 

[PCeBiker]

Actually, thinking about it some more,..

I'm sure it's not just the number of pulses that are counted before the motor kicks in, but the time between pulses too.

If you were to really slowly crank your pedals forward, the PAS probably wouldn't engage, and the number of magnets in your PAS sensor affects the pulse rate.

 

[CamelP]

I've tried all the C1 values and non of which seems to make a difference, C1 3 through 7 all works for my bike but doesn't stop the stutter when its trying to maintain top speed, what weirds me out is that the stutter is only happening at full speed, not while maintaining a speed 1-2 km/h below top speed.

 

[PCeBiker]

P2=0 disables the speed sensor input.
Give that a try.
You might go faster too.

 

[PCeBiker]

This was my top speed with my wheel in the air,..

And then after setting P2=0,..

That's also with the wheel in the air so I don't know what it's like on the road, or why it topped out at 40.7 kph.

It's supposed to go 72 kph.

 

[CamelP]

P2=0 disables the speed sensor input.
Give that a try.
You might go faster too.

That didn't do anything unfortunately.

Another update, while I'm pedalling if I start using the throttle, the stutter will stop and the bike will maintain full speed smoothly.

 

[CamelP]

Another observation:

The bike seems to hover 2 km/h below the set max speed and stutter while hovering there, however when i apply the throttle with or without pedalling, the bike easily hits the max speed target and maintains that speed without stuttering,

 

[postalstephen]

Your C14 is set to 3. That's the strongest assist. Try 1 (weakest), or 2. I had a similar experience, but I forgot what I did to resolve that. I tried many things. Also, you might want to change the P3 setting from 0 to 1. 0 is "speed control" mode. 1 is "imitation torque control".

I myself did not want PAS because my ebike PAS kicked in hard taking me to about 15 km/h . In slippery conditions you need 6 Km/h or slower sometimes.
I have a 1/2 twist grip throttle which allows me a good grip and good throttle control so I can have it help me without a surge of power.
My PAS would cause me to spin out so I disconnected it .
I always have the throttle ready when going up hill or through sand or snow . I find it is much safer now.
It's become natural to add throttle when needed . No more surge of power .