I should add that my top speed goal here would be about 12-15 mph on the flats. We would never turn down more speed, but we want the kart to be able to handle light off-road and do OK climbing hills. I realize sprockets and tire size play a huge part in this, but I wanted to start with the biggest motor the 1505 can handle then work backwards. We have some ideas and we want to play around with the figures a bit. This will be a great project to teach him about ratios and speed vs torque.
We used to sell Curtis 1505 controllers before we ran out of them around 10 years ago. They are a very well made controller and most of them have electronic braking which is very hard to find in a brushed DC motor controller these days. They are suitable for 24 Volt motors up to 500 Watts, so one 1505 controller could run one 24 Volt 500 Watt motor, or two 24 Volt 250 Watt motors.
My 12 y/o really wants to ride my other boys' power wheels around. I've decided that we will build him an e-kart to tool around in. This cart will see a variety of terrains, but nothing too crazy. I already have a couple of Curtis 1505 controllers from some past projects. I'm still in the planning process (tire size, sprockets, rpm, etc) and I am wondering what motors will the Curtis 1505 handle? I know the motors from the EV warrior (the source of my 1505s) are compatible, but I'd prefer something easier to mount, with sprocket installed, and better availability. I'd like to run a dual motor set-up with each motor driving each rear wheel. I basically want the most powerful pair of motors that won't get smoked or smoke the controller under load. I'll be running 2 - 12v 18ah batteries. Suggestions?