As the name implies, a 2-pole motor has 2 electromagnets; 1 north and 1 south. A 4-pole motor has 4 eletromagnets; 2 north and 2 south. On a 4-pole motor, the magnets are set up in a north-south-north-south configuration.

Basically, a 2-pole motor is a good RPM motor while a 4-pole motor, having more magnets, will have more torque. You might lose a bit of efficiency with a 4-pole over a 2-pole, but if you’re only running 5/6-minute races that should be ok. You’ll definitely want to look into a 4-pole if you are running the heavier ST or SC trucks.

Also, the gearing might be a little different, too. Try going up a tooth or two with the 4-pole to make up for the loss in RPM that style of motor has.