And he loves it. 5mph is really surprisingly fast. I was also surprised at how easy it would be to really hot-rod this thing. Yeah, the turning radius is crap, but it's restricted only by a couple of plastic tabs that could be ground off, and there is actually a spot to mount a 2nd gearbox, which would take it from 4x1 to 4x2 drive. Might make it tougher to turn, but would really help it get up the driveway.
And there seems to be enough space to mount a 2nd battery. Score! 2 gearboxes and 2 batteries should be enough to propel this puppy to almost 9mph. When he's older, of course.
At that point we'll need to switch the front tires to pneumatic, add a little positive caster, and maybe add a mechanical brake. This could be fun.
After getting it all assembled, we went to Target to pick up some more little plastic orange cones. I will make an autocrosser out of this boy!