A change of controller amps does not change the legality of a 250w motor, a 250 motor marked as so is still a 250w motor.Yes understand fully if it goes faster than allowed at the time of a stop it’s illegal.
And if it has an off road switch to go faster it’s illegal by a switch I mean on and off .
Say for instance a Bird Bike Bafang motor so fully compliant and factory marked at 250W .
But as soon as you change the controller you can get what is in fact 500W so I am told ?
This is done and you are using this modified bike on the road set at all the legal requirements say with an unbranded controller and LCD screen that any one with basic knowledge can access the the advance settings and make the bike go faster than is legal. But to do this the bike first has to be switched off and the settings have no password protection.
So you have been pulled over for a check and your bike is road legal .
However the inspector of the bike then knows what he is doing access’s the advanced settings makes changes in the settings to access the full power of the motor declare’s the bike now not road legal and its seized.
Who do you think would win in a court if the seizure was subsequently challenged?
It's rated power remains the same at 250w , one can try a 30/40a controller and if the battery allows it will deliver the extra input Watts though one will find in short time the clutch gears will strip and /or the windings may burn.