[Adrian Wong]

There are 14 PWM outputs and 8 relay outputs. You can use as many Speed Controllers and Spikes as you want as long as they power the motors. It would be very difficult to exhaust all those connections.

I believe it is possible to connect all the motors in the kit, supposing you had enough speed controllers, to the Robot Controller. Each could be delegated its own PWM or relay connection, allowing for individual control of each motor.

In short, you can have more than eight.