This is a matched pair of 550 High Performance motors for ride-on cars. They will work on any vehicle using 550's motors with no modifications. Just unbolt your old motor, install the pinion gears on the new motors with a set screw, and bolt them in. These motors will add significant speed over stock motors. With each pair you get:
* Torque Sleeves around each motor to add more low-end power.
* Internal Cooling Fans for extended motor life.
* Spade Connectors for quick and easy motor installation.
* Pinion gears in the size you choose.
* Bendable motor wire tabs so as not to break as easy as stock ones.
* Installation and Break-in Instructions

Select Aluminum Pinions when using stock first gears. Will not work with Hardened Steel First Gears.
Select Hardened Steel Pinions when using stock first gears or Hardened Steel First Gears.
Pinion gears from factory stock motors are not re-usable and require a 1.5mm allen wrench to install. Blue threadlock recommended.
If you're not sure what size pinion gear you need just look on your existing motor.

Motors are warrantied for up to 12 volts of SLA batteries and are often used with 18 volts (not warrantied). It is HIGHLY RECOMMENDED to add the 550 Cooling Fan Kit if you do run 18 volts. Still helpful for 12 volt vehicles too. If you're running lithium batteries you will need to use the Soft Start Low Voltage Lithium Module. We strongly recommend using our Metal First Gears when running 18 volts or more.