That reminded me of a go cart my Dad & Grandad built for me(11) and my brother(15), 2x4 "frame" with plywood. It had a kick-start Briggs & Stratton motor from a Maytag washing machine. Similar design, steering was a small cable wound around a pipe, no brakes and clutch was simply an idler pulley. The v-belt motor to axle had play, pressing left pedal put tension on idler. Seat was just wide enough both could ride and Dad working on it my brother wanted to ride alone. I saw Grandad wink at Dad, brother didn't. They sad it would be ready to ride soon.

They put a tighter v belt on it (no clutch) and wound steering cable backwards. They had rear end on a block, wheels slightly off ground. Brother got on, Dad started it and unhooked throttle spring as he kicked it off the block.

That day we had guests over and watched brother going about 15 mph all over the place, steer left it went right. It finally stopped when he ran through bushes hitting a tree.
After that I can't remember him ever riding it, and I could always get it started (I never showed him the choke lever

).
He's 75yo now and to this day hates anything mechanical.