Uploaded July 2022 | Updated September 2026, 2 hours ago
I designed this little dyno-looking thing to help my local club match the top speed of the loaner cars and anyone racing against the loaner cars to make racing more fair in the M-chassis beginner class. It works equalliy well with 210-239 mm wheelbases and both RWD and FWD cars.
It measures the voltage generated by the low Kv gimbal outrunner (80Kv) and is calibrated so that 1 V is 1 km/h. The display is a simple voltmeter. I also added a power resistor that can be activated by a switch to add some optional load.
The speed shown while the load is turned on is not accurate due to resistive losses, but it's useful to show relative differences between cars and catch obvious cheaters. A car with a 45T motor, for example, will run at much higher speed under load even if it has the same top speed as a 27T motor that is turned down with the transmitter endpoints.
The voltmeter is temporary as I have a unit with more decimals on the way that will provide more accurate speed matching.
I designed this little dyno-looking thing to help my local club match the top speed of the loaner cars and anyone racing against the loaner cars to make racing more fair in the M-chassis beginner class. It works equalliy well with 210-239 mm wheelbases and both RWD and FWD cars.
It measures the voltage generated by the low Kv gimbal outrunner (80Kv) and is calibrated so that 1 V is 1 km/h. The display is a simple voltmeter. I also added a power resistor that can be activated by a switch to add some optional load.
The speed shown while the load is turned on is not accurate due to resistive losses, but it's useful to show relative differences between cars and catch obvious cheaters. A car with a 45T motor, for example, will run at much higher speed under load even if it has the same top speed as a 27T motor that is turned down with the transmitter endpoints.
The voltmeter is temporary as I have a unit with more decimals on the way that will provide more accurate speed matching.
