Go-carts are for kids.
I should know. I made one …. 50 years ago.
2.5 hp B & S engine (borrowed from the family mower)
Willys Jeep 4-speed transmission.
Angle iron, plywood, hand tools, and a 1/4" electric drill.

It later evolved into a low slung, triangulated framed, bucket seat cart (no pictures).
For the last 5 years my brother-in-law, DJ (not that DJ), has been inviting me to join him at the Kart races. This season (2007) DJ won first place overall in the Briggs 385 Class, and was receiving a trophy at the awards dinner. So I finally gave in, and agreed to attend Karting Week in Daytona.
It turns out I knew nothing about modern karting. It seems there are over 100,000 people participating worldwide.
And they race on the major road courses; Daytona, Road Atlanta, VIR, Barber, and more.
http://www.worldkarting.com/
Entrance to the pit area:

DJ prepping his kart:

Kart fuel:

Briggs 385 Class. DJ took third in the first race. In the second race, he was leading when the drive belt on his cart shredded, smacked him in the shoulder, and caused him to take and unscheduled run through the infield.

Line up for post-race weigh-in:

The 250cc unlimited class is what piqued my interest. Speeds up to 150mph on the straightaways:

Team ZZ Top (actually a team from a Georgia motorcycle shop)

Unlimited Class on the track:

The more well-financed teams have the garages, mechanics, pit crews, and more:

I was impressed that DJ, essentially a one man team, has done so well.
DJ’s pit crew:

DJ and future racer:

Oh, and my favorite part…. The complimentary BBQ chicken dinner provided by one of the major parts suppliers.

Another nice weekend in Daytona.
jb