Kart racing is an outrageously physically demanding activity. The steering is, of course, unassisted. Your body is the suspension system. Bumps, curbs, and taps from competitors route directly through your corpus. And karting’s demands become more acutely felt as your body ages.
I started racing karts when I was 12, running weekly at a local track through the warmer months as well as traveling around the country. It was a blast. Karting was hard, even then. And I remember having days when I was sore. But I don’t remember it incapacitating me. After this, my first run in nearly 20 years, I was a broken husk of a man. In one day, I aged 30 years. I suspected I’d cracked at least one rib.
It’s not hard to see why. In a kart, there’s no isolation. No insulation. The seat is a lightly molded piece of fiberglass millimeters off the ground. There are no belts. The gas tank is between your legs. I climbed back in at the track where I raced as a kid,New York’s Oakland Valley Race Park. This is still one of the raddest kart tracks in the Northeast, about three-quarters of a mile long and bad fast, a true bullring. A lap there takes just over 40 seconds but feels like half that. How quick is the kart? It’s psychotic, even with a paltry amount of power.
Some classes run engines with less than 10 hp, still enough to see some pretty massive speeds because there are only a couple hundred pounds to push. The Solo Kart here, a chassis designed in New Jersey and built in Italy, has a 125-cc Rotax Max engine, a liquid-cooled two-stroke single-cylinder that puts out about 30 hp and has one gear. There are other karts that make the same or more power, or ones with sequential gearboxes, but the Rotax has long rebuild intervals, is dead reliable, and is plenty fast.
For the full story, check out this article from Road & Track.