Controller advice required due to meeting UK law.

[glyndwr]

Hi,
a few years back i built a fat bike with a 3kw rear hub motor, a fardriver ND72360 controller and a 72v20ah battery. The bike is awesome to be honest, its quick, comfy and has great torque to get up these hilly climbs in the South Wales Valleys.

Sadly, plod in the UK are cracking down on ebikes and Im getting to the point i am afraid of taking out the beast for a ride, i`m 61, with painful knees from working underground, and c an stay out much longer on the bike with the power it provides........ok its overkill for a bike, but i enjoyed immensely the learning curve building it and riding it.

Now though, i must row back the power and speed and make the bike UK legal, meaning changing the controller and adding a PAS sensor. Sadly the fardiver has no PAS input otherwise id reprogram it for current legislation, but thats not an option without a PAS input line.

I need to find a controller that I can program / set settings to enable throttle only to 4mph and top speed of 15mph.
Any reasonably priced controllers about that can do this. Ive read about cycle analyst but thats expensive on its own.

Any help / suggestions greatly appreciated.

Thanks, Glyndwr

 

[99t4]

Any reasonably priced controllers about that can do this. Ive read about cycle analyst but thats expensive on its own.

What is your budget?

 

[AdR]

Spintend vesc controllers are cheapest programmable ones I have seen so far. Require a bit of a learning curve but vesc tool is well documented

 

[AdR]

Kt controllers are even cheaper but not as flexable imho

 

[glyndwr]

What is your budget?

hi, as it doesnt need to supply huge amps to get to 15mph, maybe 30amps max, hoping to get something less than £100.

 

[RunForTheHills]

You could add a CAv3 to your existing controller. The CA connects to the throttle input of your controller and the PAS (or torque sensor) connects to the CAv3.

 

[gromike]

Could you limit maximum speed and delete amp/power meter?

 

[99t4]

Do the authorities do any inspections in your area? Will your 3kW hubmotor pass? Or do they just look at the controller label? How strict are they?

 

[neptronix]

Spintend vesc controllers are cheapest programmable ones I have seen so far. Require a bit of a learning curve but vesc tool is well documented

No PAS out of the box.

Baserunner is probably a good option. That controller is good for ~1000w and has a lot of options for pas, torque sensing, etc.
I would probably downsize your motor because it is still a cop magnet with a 3kw rated motor. Unless you have some magic small one..

 

[glyndwr]

Do the authorities do any inspections in your area? Will your 3kW hubmotor pass? Or do they just look at the controller label? How strict are they?

the police do a simple road side test by lifting the drive wheel and see what speed it gets too. If i label the motor a 250w continuous, and the bike doesnt get beyond 15mph i dont think thay have a case to confiscate it, as its within the legal requirement, it does mean i need to erase any original motor markings.

 

[glyndwr]

i should update my location,

I am in the UK, South Wales.

 

[glyndwr]

You could add a CAv3 to your existing controller. The CA connects to the throttle input of your controller and the PAS (or torque sensor) connects to the CAv3.

ive read alittle on the cycle analyst and that is quite expensive on its own, plus im going to repurpose the fardriver for a electric motorcycle upgrade, hence swapping to a low power replacement controller to try to make the bike a legal unit.

 

[99t4]

hoping to get something less than £100.

CA might not be too far beyond your stated budget, with the added benefits of additional useful features that may be interesting to you.

 

[stancecoke]

Kt controllers are even cheaper but not as flexable imho

I don't like KT controllers, but for this use case, they are absolutely sufficient. Easy to setup just by the display. Even a much cheaper controller like a "Brainpower" could do the job.
But to be honest, no policeman will believe the 250W sticker on a huge 3kW hubmotor....