Cadence/Speed Sensors
Cadence sensors turn the power on when pedals are turned forward and turn the power off when pedaling stops.
It will take between ¼ and ½ of a complete revolution of the pedals before the power is turned on.
Torque Sensors
Torque sensors recognise when and how much pressure is being put onto either pedal. Power will increase as the pressure on the pedals increases.
Power is available immediately pressure is put onto either pedal.
The Operation of Wisper Cadence sensor and Torque sensor
Standard
The magnetic disc can be seen on the standard equipment bikes, it is a part of the cadence sensor system and sits on the inside of the right hand crank by the bottom bracket axle. It simply tells the bike when the pedals are being turned forward at which point the power switches on. When a rider stops pedaling, the magnets stop passing the sensor and the power turns off.
Cadence sensor bikes require three magnets to pass the sensor in the correct order (pedals turning forward) before the power is switched on, magnets must keep passing by the sensor in or the power will turn off again. If the pedals stop turning, the bike will recognise this in a small fraction of a second and the power will turn off, hence the reason we do not need vulnerable brake cut outs.
Torque Power Pack
On Wisper bikes fitted with the Torque Power Pack bikes the torque and cadence sensors are housed inside the bottom bracket where the pedals are connected through the bike frame.
The Wisper Torque system works in a completely different manner to the standard Wisper. Through the torque sensor the system measures the pressure a rider is putting onto the pedals. Pressure on the pedals turns the power on and the torque sensor reads the amount of pressure being exerted. The more pressure a rider puts onto the pedals the more power will be demanded from the motor.
So… if the bike is starting from standstill, encounters a hill, a strong headwind or if the bike is heavily laden, the torque sensor will recognise that more pressure is being put onto the pedals and the bike will offer more powered assistance. It’s very simple and very clever!
Either the left or right pedal will activate the torque sensor.