Under Standing Your Pedal Assist
What makes an e-bike better than a normal bike? The pedal assist system (PAS).
Since we pride ourselves in a fully customizable e-bike experience, you can change the reaction of the PAS for every gear, in every mode, and fine-tune each type of reaction as you see fit.
Of course, you would need to know what it is you want to fine tune in order to take full advantage of a customizable system. The descriptions below are exactly how you will find them in the latest CYC Motor mobile app for BAC controllers.
It’s important to note that there are two parts to the system: a pedal (or cadence) sensor and a torque sensor. Most e-bikes out there only work with a pedal sensor, but since we know just how important torque is in your riding feeling, we provide both.
Hardware Input Information
These 2 parameters tell you if your torque sensor is working, and how you would like your overall assist to work.
Torque Sensor Voltage
The Torque Sensor Voltage can be used to confirm that the torque sensor is connected and that it works properly. How do you know? If the torque sensor is plugged in, the voltage reading should be 1.5V. Then, you can put some force onto the pedals and if the voltage changes, your torque sensor is working correctly.
Control Command Source
Next, you’ll see Control Command Source. This selection allows you to decide if you only want to use PAS, only throttle, or both. This is generally a preference from rider to rider:
Throttle and pedal sensor
Throttle or pedal sensor
Under “Settings” in the mobile app, you’ll find the “Pedal Assist” tab. Select it, and you will find 4 main settings categories for you PAS.
Pedal Sensor Configuration
This is the pedal (or cadence) sensor settings.
Pedal Sensor Type
Firstly, we have the Pedal Sensor Type. There are 4 types of pedal sensors and give you the option to use only the pedal sensor, only the torque sensor, or both.
Single Hall Reverse is only for the Gen 1 X1 PRO motors. If you have a Gen 1, you should only use this sensor type as the Gen 1 motors do not have torque sensing.
Single Hall Torque (LDS) is selected to activate both the pedal (or cadence) sensor as well as the toque sensor.
Axle torque is to activate only the torque as pedal (or cadence) sensing will not be activated.
Single Hall is then only for pedal (or cadence) sensing where the torque sensor is not active.
Pedal Speed Sensor Pulses Per Revolution
Then, you have the Pedal Speed Sensor Pulses Per Revolution. This is a torque sensor specific parameter. For the current torque sensor, there are 36 magnet pulses for one revolution of the pedals.
Pedal Sense Delay
This is the number of magnet pulses that must be detected before the PAS is activated. Most prefer having it engaged as soon as possible so we have set the value to 1. If PAS engages too fast for your preference, you can set it higher.
Pedalec Maximum Timeout & Pedalec Minimum Timeout
The Pedalec Maximum Timeout & Pedalec Minimum Timeout are two parameters that work together and effect your PAS response for deactivating. What this means is that between 50ms to 100ms, the controller will start probing for change in pedal speed. If there is no change in pedal speed within this timeframe, the PAS will be deactivated. This time period can be set longer or shorter by changing maximum and minimum values.
Pedal Speed Map End
Then, the Pedal Speed Map End is the cadence value that will give you full gain when pedaling, i.e. the speed at which the torque sensor will feel most powerful. A lot of reviews cover this concept with other e-bikes as it’s often said that when they try pedal really fast, the power output feels lower. There is an ideal pedal speed at which the motor feels the most powerful when riding, and you can actually set this value according to your ride style.
Pedal Speed Map Offset
The Pedal Speed Map Offset is related to the pedal speed required to activate the PAS. The lower the value, the slower you can pedal and still engage pedal assist, and vice versa. The value must remain between 0.3-0.5. So, when you are riding more technical terrains, you might want to set this lower than you would for riding on an open road.
Assist Cut Out Distance
Finally, the Assist Cut Out Distance is set to 1.5m by default and is the distance before PAS cuts out. This is approximately one-wheel revolution and is required for smooth operation. This can only be made shorter if you have more magnets on your wheel. If you only have 1 magnet, then the controller will only be able to pick up signal after 1 wheel revolution. If you install 2 magnets, then you can set this lower to 0.75m and the controller will be able to pick it up accordingly.
Torque Sensor Configuration
Torque Sensor Gain
The Torque Sensor Gain is a value related to your specific torque sensor. For the latest torque sensor, this value is calculated to be 69 Nm/Volt. Do not change this value as it is used for informational purposes.
Pedalec Power Gain
Then, you have the Pedalec Power Gain. You can adjust the sensitivity of the torque sensor by changing this value. If you want the torque sensor to be more powerful, increase this value.
Decrease it if you want it less powerful. Pedal Power Gain is the factor of input to output. Meaning that if you pedal at certain strength, it will be multiplied by this factor before giving an input to the motor.
Axle Torque Sensor Offset Voltage & Torque Sensor Offset
The Axle Torque Sensor Offset Voltage & Torque Sensor Offset is set to determine at what voltage input, the system should remain inactive as every torque sensor has a reading once it’s connected. Just because the torque sensor is connected, doesn’t mean you want it to activate without any human input. The Torque Sensor Offset should not be set lower than the Axle Torque Sensor Offset Voltage. Torque Sensor Offset voltage can be set by reading the value form Axle Torque Sensor Offset Voltage. This value should be 1.55v. If it is close to 0V, then no torque sensor is connected.
All the torque sensors provided by CYC are set with a base voltage of 1.55V so there is no need to change the Torque Sensor Offset.
Pedalec Initial Torque
The Pedalec Initial Torque is the amount of torque supplied from the motor to account for the lack of pressure from the opposite leg. For example, when you are starting on a hill, it is difficult to maintain pressure on both legs and keep a constant cadence. This helps to get things going in these situations. Increase this value for more initial torque when the PAS is engaged.
Pedalec Deadband Torque
Next, we have the Pedalec Deadband Torque which is the amount of torque required before activating the PAS. The higher this value is, the harder you must pedal to activate the pedal assist.
PAS Ramp Times
The final 2 parameters for your PAS settings, are the ramp times. These work similar to the ramp times in the Throttle settings and affects the systems response time.
Pedalec Positive Motoring Torque Ramp
The Pedalec Positive Motoring Torque Ramp is the amount of time it takes to reach the desired input. If 100% pedal power is given to the controller, the motor will take 50ms to reach 100% power.
Pedalec Negative Motoring Torque Ramp
Lastly, Pedalec Negative Motoring Torque Ramp is the amount of time it takes for the motor to have no response after you stop pedaling. If the motor was running at 100% power, and there is no more pedal input, it will take 50ms for the motor stop responding.
Common Questions About Pedal Assist
Q: Which parameters should I look at to give me more/ less power when pedaling?
A: To adjust the power of your pedal assist, make sure you are in Single Hall Torque (LDS) or Torque mode in you Pedal Sensor Type as your power output is toque based. Then, go to Pedalec Power Gain under Toque Sensor Configuration. If you want the torque sensor to be more powerful, increase this value. Decrease it, if you want it less powerful.
Q: Which parameters affect my pedal sensitivity?
A: The 2 parameters under PAS Ramp Times will affect how quickly the PAS will respond.
Q: How can I set my PAS to start up faster/ slower?
A: To change how fast your PAS activates, you can look at your Pedal Sense Delay and Pedal Speed Map Offset under Pedal Assist Configuration, as well as your Pedalec Deadband Torque under Torque Sensor Configuration
Q: How can I get more power when I activate the pedal assist?
A: To adjust the power of your pedal assist when starting, make sure you are in Single Hall Torque (LDS) or Torque mode in you Pedal Sensor Type as your power output is toque based. Then, go to Pedalec Initial Torque under Toque Sensor Configuration.