Got the motor, chain and sprockets installed, and cut off the weird connectors on the motor's harness and installed a more generic set of Molex connectors from Radio Shack. Just so I can replace pins and housings later should they get damaged, without having to mail order parts and wait a week plus.
http://frederic.midimonkey.com/booto...r/IM002111.JPG
Even though I don't have the steering column completed (or installed), I decided I wanted to test things out while the last layer of resin on the body dries.
I clamped the steering straight ahead using a pair of vice grips, cobbled up a simple wiring harness that allowed me to hold the "go" pushbutton as well as the 5k throttle potentiometer, and sat on the chassis with my legs hanging off the front, balanced precariously on my ass on the open frame chassis.
I pondered for a moment before I pushed the "go" button, wondering how bad of an idea this is. But, it's only a 300W motor geared down 5.something to 1, so how fast can this be?
So I push the go button. Nothing happens.
Aaah, one of the battery connections hadn't been tightened. Fixed that and sat back on the chassis, again legs hanging off the front.
Push go button. Yaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaa!
I've concluded several things.
1. It needs a seatbelt for my son when I put the finish the body and put it on the chassis.
2. Vice grips don't hold the steering straight and fall off on the first bump in the lawn.
3. The body needs to have an additional panel between the passenger seat and the motor, as the motor gets freaking hot. Grabbing it for balance was a bad idea.
4. #3 was further emphasized by my old t-shirt getting sucked into the chain and the tiny motor sprocket. Tore a nice chunk out of my shirt. It's okay because this particular t-shirt has holes in it from welding but that's not the point.
5. I need to device some kind of braking. I thought the motor with the built in controller had this feature built in, but when one closes the "brake switch" all it does is put the controller and the motor into sleep mode - it still freewheels happily.
I'm thinking now about the throttle... instead of attaching the throttle potentiometer to the gas pedal, what I'll do instead is wire the pushbutton behind the pedal, for an on/off effect, and put the pot at the back of the chassis on a metal plate, with a "max speed" knob, so speed cannot be controlled from inside the car, at least for now since my son's only 19.5 months old. This way I can set things to a really slow, baby-tame speed and I can run after him if necessary. At full speed I could barely hold onto the chassis (though other than the scorching hot motor there wasn't much to hold onto!) and I don't need my son flinging himself into danger at high rates of speed.
Amazing how much kick a puny 5" diameter, 300W motor has. This was with a single, 12V battery from the old riding mower, I can only imagine how it would be with 24V like the motor is expecting. Might be why it got so hot too - not enough voltage so it drew more current.
Well, that's enough testing for one day. Gonna go ice my hand.
Cute guy and HAPPY which is the most important! 
