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Dirt Bikes explained:

What is a Dirt Bike? A lightweight motorcycle designed for use on rough surfaces, such as dirt roads or trails. Sometimes, it's also called a trail bike. It's designed chiefly for recreational or work use over roadless, rugged terrain. A very detailed description would be that it is a two-wheeled vehicle powered by an engine. The wheels are in-line, and at higher speed the dirt bike remains upright and stable by virtue of gyroscopic forces; at lower speeds continual readjustment of the steering by the rider gives stability. The rider sits astride the vehicle on a seat, with hands on a set of handlebars which are used to steer the motorcycle, in conjunction with the rider shifting their weight through their feet, which are supported on a set of "footpegs" or "pegs" which stick out from the frame.

Sport models are often built with a mind towards motocross or dirt track racing, either in the design of the machine or at least in the marketing of it. To be successful at motocross racing, it must have light weight, high power, good suspension and a low center of gravity. There are many other types of riding and racing such as Baja (desert racing), hill climbing, and trail riding.

The chassis is typically made from welded aluminium or steel struts, with the rear suspension being an integral component in the design. Some motorcycles include the engine as a load bearing (or stressed) member; this has been used all through bike history but is now becoming more common. The fuel tank is usually mounted above the engine. This tank is generally made of stamped, brazed or welded sheet steel, or blow-molded high-density polyethylene. The wheel rims are usually steel, either with steel spokes and an aluminium hub, or 'mag' type sandcast aluminium. Performance racing dirt bikes often use carbon-fibre wheels, but the expense of these wheels is prohibitively high for general usage.

Some of the most popular manufacturers of dirt bikes are:
-Honda
-Kawasaki
-KPX
-Yamaha
-Suzuki

Important Dirt Bike Safety Tips:

Follow these safety tips to make riding both fun and safe!

Before You Ride:
-Familiarize yourself before you ride. Read and understand the instruction manual and observe all safety and warning labels. Check the controls.
-Wear the proper clothing/pads including helmet, elbow pads, knee pads, wrist guards, gloves and shoes.
-Check the equipment including the nuts and bolts, steering, brakes and controls, frame (for stress and fractures) and tires (for wear). Inspect your dirt bike thoroughly before each use for loose or missing parts.

When Riding You should:
1.Always wear a helmet and other protective gear.
2.Never ride on public roads - another vehicle could hit you.
3.Never ride under the influence of alcohol or other drugs.
4.Never carry a passenger on a single-rider vehicle.
5.Ride a dirt bike that's right for your age. The guidelines are:
a. Age 6 and older - Under 70cc
b. Age 12 and older - 70cc to 90cc
c. Age 16 and older - Over 90cc
6.Supervise riders younger than 16
7.Ride only on designated trails and at a safe speed.

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Dirt Bike Questions and Answers, Tips, Troubleshooting Section:

The temperature has suddenly dropped. Your choke is frozen and you can’t get the engine started. It would be easy enough to haul the machine into the heated garage, but you’re way back in the brush. What do you do?

Some ATVs have primers, and a few hits usually get things going. Otherwise, remove the spark plug and pour a small amount of fuel down the hole. Replace the spark plug and hit the starter. You may have to do this three or four times, but the engine should kick over. Once it’s running, be sure to warm it up completely, using an elastic band to hold the throttle open. When you’re ready to roll, check the brakes and belt to remove any ice buildup. And next time you’re out in the cold, park the quad with the choke in the open position. Also, take into account that you’ll use about a third more gas in cold weather than in warm.