Karting is an open-wheel small motorsports vehicle that has four wheels. Various names for these vehicles are; kart(s), go-kart(s), go-cart, or gearbox/shifter karts depending on the design. They vehicles range from go-karts that you get at a farm or chain store to full out race vehicles that have dedicated scaled-down racing circuits. Karting is part of the ladder system to the higher ranks of motorsports such as Formula One, NASCAR, Indy, and World Rally Championship racing. Karts range from pedal karts to recreational go-karts intended for the general public limited to lower speeds to some known as Superkarts that can reach speeds exceeding 260 km/h & 160 mph.
American Art Ingels is generally accepted to be the father of karting. A veteran hot rodder and a race car builder at Kurtis Kraft, he built the first kart in Southern California in 1956. Instantly popular, Karting rapidly spread to other countries, and currently has a large following in Europe. The first kart manufacturer was an American company, Go Kart Manufacturing Co. (1958). In 1959, McCulloch was the first company to produce engines for karts. Its first engine, the McCulloch MC-10, was an adapted chainsaw two-stroke engine. Later, in the 1960s, motorcycle engines were also adapted for kart use, before dedicated manufacturers, especially in Italy (IAME), started to build engines for the sport. - Wikipedia
Pictured at the top of this page is a pedal kart. A kart like this may be a kids first driving experience. These karts cost $110 - $950 new.
A kids electric kart can be a 12-24v electric kart, normally with two speeds and a reverse. Some models have adjustable speed. Price range on these is similar to the pedal car $200-$300.
These type of karts cover a broad range of basic design and various manufacturers. Normally a 5-15 horsepower motor and normally for off-road use. Some of these go-karts have bigger tires and are specifically called Off-Road go-Karts. Price range on new is around $700 - $1500.
These karts are found in many major cities. You typically do not buy these karts, but pay anywhere from $15-$50 to drive/race them on a dedicated track for about 8-10 minutes.
These are dedicated racing karts for purposefully built dirt oval tracks all around the world. There are racing classes from ages 5 to as old as one is able compete. Cost on these range from used to new is around $1000 - $5000.
These are very similar to the dirt oval karts with chassis designed for left and right turns on road course generally around 3/4 mile long. The price range on these is around $1000 used to $8500 for new.
A shifterkart is a kart that has gearbox that you use a clutch to when starting from a stop. Once rolling then you shift without the use of the clutch. Normally a five or six-speed gearbox is used. These karts go 0-60 around 3 seconds and can reach 3Gs of force while turning. The cost for used is around $1500 - $9000 for better equipment. New can run as high as $15,000 depending on options.
SuperKarts are similar to a shifterkart except the engine displacement is normally twice that of a shifterkart. The SuperKarts is a shifterkart with an aerodynamic body package for higher speeds and normally driven on full race tracks like Laguna Seca that sports cars race on. Price range on these is around $4000 - $30,000.
There is an old adage in racing that whatever you think you are going to spend double it. I'm not sure that exactly true based off my racing experience, however even though kart racing is one of the most affordable forms of racing it is still expensive and for most Americans out of the reach. If you have a passion for racing; starting out at your local indoor kart track makes the most sense y, then you can find out if you have a knack for it, or if it's something you would enjoy paying more money to do. For indoor karting it may take you 10 to 20 trips to find out if you are natural or have a skill for driving. It's not something you normally just get in and go out and your amazing the first time. So you're looking at around $500 to start to get a feel for what racing would be like. The bonus of indoor karting for the most part it's very safe compared to racing on a circuit where the wheels are open and if you touch you might flip the kart. Karts are dangerous and fatalaties do happen occasionally, the risk are real.
After you have indoor karted and you decided you're willing to take the risk to go racing, visit your local track and see what's popular in your area. Karting is somewhat of a segmented sport, what might be popular in one part of the country may not be popular in another. If you have plans to race nationally you'll need to research what's popular on a national scale this may mean racing by yourself or small class in your area.
There are a lot of kart chassis and different engine packages to choose from. To make sure you don't lose out on your money it's a good idea to buy something there is an active class somewhere in the USA, as the rules are always changing this has put some karts not eligible to race. The good thing about these karts are they can be had for relatively cheap and you can go have fun on practice days at your local kart track, you may just not have a class that you can enter on race day, but still have a lot of fun just driving and learning if you like the sport.