Power/ speed limiter for overpowered bike

[sam_uk]

Hi I just got a bike that I suspect is overpowered for the public road.

It's a kit bike that was constructed before 2000, so the open throttle is acceptable I think?

It has quite a large motor so the person who rated the motor & put the 250watt continuous rating sticker on it must have been quite conservative.

I think it's capable of more than 15 mph which is the bit that makes it non road legal.

Is there a device that I can put in the circuit that will limit the draw to 5amps (@48v)? I think this would limit the speed to the required 15mph?

Thanks

 

[trex]

the controller controls the power to the motor, the LCD provides a mean to limit the speed of the bike. If you want to limit the power, these two components need to be brought up to date.
Post a picture of the bike and motor, we'll try to help you.

 

[sam_uk]

OK i'll post pictures once I collect it.

Just thinking sideways, as I just need to limit the speed can't I do that by simply restricting the throttle movement? Just put in a bolt/assembly that stops the throttle moving past the 15mph position?

 

[trex]

No. To be legal, you need a mean to measure the speed and tell the controller when that speed limit is reached. The speed limit is usually programmed via the LCD. Cheap bikes that do not have LCD may implement speed limit by counting the pulses that the controller sends to the wheel times the diameter of the wheel.

 

[Deleted member 4366]

Cutting the power won't limit the speed. You need a proper speed limiter. We need to know exactly what you have to be able to advise further.