Removal of speed limit on Dapu controller

MartinHøier

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Hello everyone,

I have an E Bike with a Dapu M123 FS 250W, 36V motor on. And a Dapu contorler to go with it.
I have a pedal torque sensor on the grank.
But since i live in Denmark the limit on an E Bike is 20 km/h.
On Dapu's website it states that the motor can go up til 25-32 km/h.
But i guess that there is a limit in the controller.

Is there anyway for me to remove that limiter ?
Or get a new controler?

I dont need to go 50 km/h, but would just be nice to get assistance up to the motors max and not be limited.

Hope you Guys can help me out.

Cheers
 
There's many ways that manufacturers limit the speed. Some can be changed by the owner.
1. Two single wires that come out of the controller, often as a loop, which has to be cut, sometimes with connectors, which have to be connected or disconnected, and sometimes with a convenient adjuster screw.
2. LCD settings. By pressing the right buttons, you can get to the speed limit setting. Show a picture of your LCD. Sometimes you can change the wheel size setting to a smaller one to give a lower calculated speed.
3. A bridge on the controller's pcb. Not so common now, but you didn't say how old your bike is
4. Controller's cpu programming. There's not much you can do about that
5. Motor winding speed. Not very common because the motor runs slower with a low battery compared to a fully charged one. I doubt that 20 km/h would be limited by the motor.

The controller has to get a speed signal from somewhere:
1 Separate hall sensor in the hub. You can intercept the white wire at the controller and put a sensor on your chainstay and a magnet on the back of a pedal. That w
2. Spoke magnet and external wheel-speed sensor. Some controllers allow maximum speed if you move the magnet away from the sensor so that there's no speed signal. Others default to a limit or go to sleep after a few minutes.
3. Use a signal from one of the motor hall sensors. There's nothing you can do about that.
 
Thanks,

Ill try and take a Picture of the controller box, so you can see the wiring.

The bike is for 2014.

This is the LDC thats on my bike. http://www.dapumotors.com/portfolio/dplcd-i/

I've attached a Picture of the controller i have and a Picture of ( what i think ) is the schematic. Dont know if its any help.

And to be honnest, i have no clue about how to remove the speed sensor and magnet. im not all that technical.

Hope this helps. If not let me know what else to do.

Thanks a million
 

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The schematic you posted shows a 3 pin connector IV "Gashebel". If that is present at your controller you could plug in a throttle and try if it will go faster than 20km/h.
 
I think your only chance is with the LCD.

Switch on and press the set button within a few seconds.
That should go to some settings. A short press of the button will jump to the next setting. Adjust each setting with the up and down buttons.
See if there's advanced settings. While you're in the settings, press and hold the set button for about 10 seconds to see if it goes to different settings.

Let us know if either of those work. You might find the wheel size in the first settings. See what happens if you change it to 20", but don't forget that the display will show the speed wrong, so it still won't show more than 20 km/h.
 
Dapu hubs are fitted to BH Easy-motion bikes and the only way to do this is to replace the motor with a 350w one bought from the USA. I haven't done it but others have. On a repair stand the EU achieves 30 and the USA 45 kph. Such a solution might work for you. The other way of doing it is to add a small battery pack in series which increases the voltage to a nominal 48v but that's getting untidy and those that have done this find their battery has poor endurance That might be what awaits you if you succeeded however you did it.
 
James Broadhurst said:
Dapu hubs are fitted to BH Easy-motion bikes and the only way to do this is to replace the motor with a 350w one bought from the USA. I haven't done it but others have. On a repair stand the EU achieves 30 and the USA 45 kph. Such a solution might work for you. The other way of doing it is to add a small battery pack in series which increases the voltage to a nominal 48v but that's getting untidy and those that have done this find their battery has poor endurance That might be what awaits you if you succeeded however you did it.

I'm not sure that any of that is right. The E-Motion Neos were restricted in the controller software. Changing the motor would have no effect.

It's the same with the booster battery. The controller still limits the speed. If you watch the videos where those guys did the booster battery modification, they never said that it increased the no-load speed, but it does increase the speed in all situations where the bike couldn't reach the 25 km/h speed restriction.

The speed limit can be by-passed by using a new controller, but if you have a torque sensor, you'd probably need to change to a cadence sensor. If the controller uses the hub sensor white wire to get the speed signal, you can interrupt it and resend it at half the frequency with a dual flipflop or PIC (Arduino Nano). Somebody had success with their Neo using both those devices.
 
I have the same DAPU controller and am trying to also raise the ~12 kph speed limit. Holding down Set for 10 seconds lets me adjust the wheel size, but pressing or holding Set again simply exits to the controller display modes. DAPU has not responded to email queries. When the controller first activates it lights up all the symbols on the screen, and one of them is a Max Speed symbol, but I am not confident that entering that setting is allowed. Thanks for the suggestions, and if anyone has any more, I'm more than willing to give it a try. I feel like I've tried all permutations of button combinations to get into it, but who knows.
 
If you really want the extra speed, you can change the controller and LCD, and use a normal PAS instead. The one from PSWPower should workOK.

http://www.pswpower.com/peng/pic.asp?ModID=PicS224&TypID=S220052
 
Hi,
Did anyone find a solution for this controller / lcd?
The manul says to hold the set button for 10 seconds - but doing that just turns it on - then off again.
 
Yes
Hold "set" for 6 sec
when you see wheel size settings klick "set" one more time, then push "up arrow"
 
Hi,

you can go to a BH Dealer and hope he is a nice guy.
He has the dealer or BH Software and can change all of this.
But he needs to want to do it :roll:

All is possible !
 
Do ebiketuning.com do a badassbikes box that is compatible?

These work by fooling the controller into thinking the motor is going half the speed that it is effectively doubling the top speed, although your speedo will be out on the LCD, you can use a phone app as a speedo replacement.

They do them for the most popular off the shelf ebike systems like Yamaha, Shimano, Panasonic etc.
 
If you can change the wheel size on the display, you could try setting it to the smallest size. The speedometer will not be accurate anymore and should indicate the same top speed but the bike would actually be going faster.
 
I know it's an old topic, but I just got a cargo bike with same controller and motor, which is limited to 12mph... it has a front 20'' wheel with the motor on it, changing the wheel diameter to 16'' kinda work, but still not able to go faster than 14-15mph, and of course, speed and so on the display is wrong. Anyone with a better solution?
 
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