Help! | How to Hack this Controller

[byebyepetrol]

With 1000km under its wheels my bike is fantastic but goes no faster than 37-40kmh ( 23-25mph).

It feels like it has a limiter after 37kmh. The effort required to surpass that speed is significant, as if it has
some closed circuit switch after that speed.

Assuming it has a speed limiter is there a way to switch it off?

I go faster on my roadie but consequently knackered at the end of the ride compared with the electric bike.

Bike;

Specs:

Heat Sink:

Electronics :

Chris.

 

[Lebowski]

are you sure there's a limiter and the powerloss is not due to the battery voltage being too low ?

 

[byebyepetrol]

Hi Lebowski,
How can I tell ?
Even if it's fully charged it still tops-out at around 37kmh.

Chris.

 

[Lebowski]

normally you'd look at the specs of the motor, or try 48V if the controller can handle that.
What you could try is a no-load speed measurement (wheel in the air, full throttle, measure wheelspeed)

 

[byebyepetrol]

Wheel in the air = 37kmh. What do you think is the limiting factor? It seems to get to its limit pretty quickly.

 

[d8veh]

You set the speed limit in the LCD. It's normally press and hold the + and - buttons to enter the setup. Some LCDs have a maximum of 40 km/hr in the setup, but you can overcome that by removing the magnet on the wheel from the sensor, though you'll lose the speed display. Some controllers will revert to 25km/hr if they lose the speed signal, so that hack doesn't always work. I can't see which display you have, so it's not possible to be more precise.

 

[byebyepetrol]

Hi d8veh,


Top Menu:

Sub Menu:

 

[Lebowski]

maybe you can fool the system and change the wheel diameter to 20 inch ?

 

[byebyepetrol]

Hi Lebowski, tried that ;0)
Any smaller setting like 20" makes no difference apart from the no-load speed hitting 24kmh on the display.
The max revs seem to be the same (guessing here).

 

[Teh Stork]

Could he be hitting the point where the BEMF equals the battery voltage+1 diode drop? In that case, he will definitely feel a significant braking force.

Does this "limiting speed" vary by as much as 10-15% between a full and empty battery? (Empty battery, lower speed before threshold is reached)

 

[byebyepetrol]

Hi Teh Stork; good idea. Will check.
Chris.

 

[alsmith]

Are any of those wires coming out of the controller just connected to another wire coming out, but going nowhere else? Or 2 wires not connected to anything?

 

[byebyepetrol]

Hi Alsmith,

The thinner black goes to the PAS, one thick to motor, the other thick to brake switch and display.
The red/black thick from battery.

 

[alsmith]

Sorry, I mean the wires from/to the controller, not the display. A lot of 'law abiding' controllers used a linked connector to comply with the 15mph limit imposed by any countries laws/regulations, removing the link removed this limiting. That's not to say that a manufacturer couldn't just build the limit into a controller if they wanted too. Look for a loop back wire to to/from the controller that could be switching he speed limit on.