R/C Vehicle Speed Calculator For Use With Brushless Motors

This javascript/HTML calculator is used to find the approximate maximum speed of your Brushless Motor powered R/C vehicle. Many factors have been taken into consideration to make this calculator as accurate as possible, but certain variables like vehicle weight, battery quality, drivetrain drag, etc can have an effect on the actual speed. Also, at speeds at or over 45mph, wind resistance, drivetrain drag, etc becomes a serious factor and may reduce the accuracy of the calculations further. Just keep in mind that the result is the maximum theoretical speed based on ideal conditions. Most likely, the actual speed will be a little less.

Fill in each of the required values (denoted by *) and press the "Calculate Speed" button to display the results. Some fields can be automatically filled with pre-determined values by selecting from the associated drop-down list. Fields beginning with †† are not required but will provide a more accurate speed calculation. If you do not know these values, leave them at their default value.

* Enter Front/Rear Differential Gear Ratio (?):
* Enter Transmission Gear Ratio (?):
†† Enter Additional Gear Ratio (?):
* Enter Spur Gear tooth count (?):
* Enter Pinion Gear tooth count (?):
* Enter total battery voltage (?):
* Enter kv rating of brushless motor (?):
* Enter tire diameter in inches (?):
†† Enter the added radius of tire
"ballooning" in inches (?):
†† Enter Current draw in amps (?):
†† Enter motor resistance in Ω (?):
†† Enter vehicle type (?):
 
           
 
Spur/Pinion Reduction Ratio (?):
Total Reduction Ratio (?):
Tire Circumference (?):
Total Motor Speed (?):  
Theoretical Maximum Vehicle Speed (?):
Drag-Adjusted Vehicle Speed (?):  
Calculated Loaded KV Value (?):  
Calculated KT Constant (?):  
Calculated Motor Torque (?):  
Calculated Axle Torque (?):  
Calculated Motor Power (?):