Yes you can run 20S or even 30S. I have done both. Programming determines whether it's safe. But I wouldn't run 20S on the stock controller. People have done it but you are at the edge of component voltage ratings. Not good for reliability.
Also I tried the ASI BAC2000 controller on this thing. The setup would be straightforward if there was better documentation although trying to autotune halls on the Cyclone is a ridiculous exercise I was never able to complete satisfactorily. I did run on sensorless which works well once you're going, but not from a stop. Unfortunately I wasn't able to get a "fast" throttle response even with torque ramp and power settings adjusted accordingly. The torque ramps up too smoothly / slowly. Overall this controller is not even close to being worth the money...even if all that stuff worked it's still very expensive for what it is and support is practically nonexistent.
Also I tried the ASI BAC2000 controller on this thing. The setup would be straightforward if there was better documentation although trying to autotune halls on the Cyclone is a ridiculous exercise I was never able to complete satisfactorily. I did run on sensorless which works well once you're going, but not from a stop. Unfortunately I wasn't able to get a "fast" throttle response even with torque ramp and power settings adjusted accordingly. The torque ramps up too smoothly / slowly. Overall this controller is not even close to being worth the money...even if all that stuff worked it's still very expensive for what it is and support is practically nonexistent.