![Image of a Reedy S-Plus 12.5x24.2mm rotor for Reedy S-Plus Spec class motors.](https://cdn.prod.website-files.com/5e5ae7175a542c69f8e338b4/637ca592f0adefb57a1dfe7d_asc27414.jpg)
RC racers today are always looking for an edge, and sometimes that even included changing the size of the rotor in their brushless motor.
Shorter rotor
- Less torque
- Higher rpm (top speed)
Longer rotor
- More torque
- Require tall gear ratios (large pinions) to get speed
Please also consider rotor diameter when choosing a rotor.