Monster Truck Week Part 4: Extreme Lawnmower Racing

Apparently there has been organized lawn mower racing in the U.S. and in England for more than 30 years, with the annual Fourth of July Race in Twelve Mile, Indiana and 12 hour lawn mower race in Wisborough Green, England the oldest known events. Who knew? The first rule of lawnmower racing is take off the blades (no not "you don't talk about lawnmower racing"). Events are open to all self-propelled rotary or reel style riding lawn mowers. The mower must originally have been designed and sold commercially to mow lawns and it must remain suitable for lawn cutting (apart from the removal of the blades). After that, the degree of modification of the lawnmower decides what racing class you are in. I'm pretty sure this was an anything goes kind of race but apparently there are 4 different classes of lawnmower race:

Stock Class - As delivered from the factory.
IMOW Class - (Int'l Mowers Of Weeds) Front engine, highly regulated.
Prepared Class - Prepared (modified) drive train, engine, etc.
FX Class - (Factory Experimental) Major modifications allowed.

It seems that lawnmower racers never race for money either, just trophies, bragging rights, etc. You might be inclined to chalk this all up in the "guys are stupid" category, but it just looks like so much fun that I can see why they do it. It's just like go-carts but sillier.
p.s. I remember being allowed to mow the lawn on the riding mower when I was little and how much fun that was. Good times. Why not turn it into a race?