A motorcycle (also called a motorbicycle, motorbike, mocyc, or motocycle) is a single-track, two-wheeled motor vehicle powered by an engine. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions. Being the most affordable form of motorized transport, in some parts of the world they are also the most widespread transport in Thailand. Motorcycle brands available in Thailand.
Motorcycle construction is the engineering, manufacturing, and assembly of components and systems for a motorcycle which results in performance, cost and aesthetics desired by the designer. With some exceptions, construction of modern mass-produced motorcycles has standardized on a steel or aluminum frame, telescopic forks holding the front wheel, and disc brakes. Some other body parts, designed for either aesthetic or performance reasons may be added. A petrol powered engine typically consisting of between one and four cylinders (and less commonly, up to eight cylinders) coupled to a manual five- or six-speed sequential transmission drives the swingarm-mounted rear wheel by a chain, drive shaft or belt.
Motorcycle fuel economy benefits from the relatively small mass of the vehicle. This, of course, relates to how the motorcycle is used. One person on a small motorcycle traveling a short distance is generally very economical. However, a large motorcycle generally has bad aerodynamics compared with a typical car, poor aerodynamics of exposed passengers and engines designed for goals other than fuel economy can work to reduce these benefits. Riding style has a large effect on fuel economy. Find out which of fuels suit your needs best.
Very high fuel economy equivalents can be derived by electric motorcycles. Electric motorcycles are nearly silent, zero-emission electric motor-driven vehicles. Operating range and top speed suffer because of limitations of battery technology. Fuel cells and petroleum-electric hybrids are also under development to extend the range and improve performance of the electric motors.
Different types of motorcycles have different dynamics and these play a role in how a motorcycle performs in given conditions. For example, a shorter wheelbase would generally make a bike lean faster and would be quicker around corners compared to a longer wheelbase. Longer wheelbase on the other hand provides more stability in a straight line. Motorcycle tyres have a large influence over handling.
Motorcycles must be leaned in order to make turns. This lean is induced by the method known as counter-steering, in which the rider steers the handlebars in the direction opposite of the desired turn. Because it is counter-intuitive this practice is often very confusing to novices - and even to many experienced motorcyclists.
Short wheelbase motorcycles, such as sport bikes, can generate enough torque at the rear wheel, and enough stopping force at the front wheel, to lift the opposite wheel off the pavement. These actions, if performed on purpose, are known as wheelies and stoppies respectively. If carried past the point of recovery the resulting upset is known as “looping” the vehicle.
There are three major types of motorcycle: street, off-road, and dual purpose. Within these types, there are many different sub-types of motorcycles for many different purposes.
Street bikes include cruisers, sportbikes, scooters and mopeds, and many other types. Off-road motorcycles include many types designed for dirt-oriented racing classes such as motocross and are not street legal in most areas. Dual purpose machines like the dual-sport style are made to go off-road but include features to make them legal and comfortable on the street as well.
Each configuration offers either specialized advantage or broad capability, and each design creates a different riding posture.
Motorcycle rider postures
The motorcyclist's riding position depends on rider body-geometry (anthropometric) combined with the geometry of the motorcycle itself — falling along a spectrum of three basic postures.
Sport - the rider leans forwards into the wind and the weight of the upper torso is supported by air pressure - but only as long as the motorcycle is traveling at speed (typically 50mph/80kmh and upwards). The reduced frontal area cuts wind resistance and, where legal restrictions permit, allow higher cruising and top speeds to be reached. However, at low-speed this position throws the weight of the rider onto the arms instead, and this is quickly tiring to the wrists of unfamiliar riders. Moreover, the sports position makes it more difficult for the rider to look around and foot through traffic. Very narrow, swept-back handlebars (or “clip-ons”, short stubs clamped to the telescopic fork tubes) became illegal when they trapped the riders thumbs against the fuel-tank or unpopular because of the restricted steering movement and large turning circles required. Almost all these models now have full-fairings as standard and often come with almost complete engine enclosure.
Standard - the rider leans forwards slightly (“Tourer” motorcycles use this position). The rider benefits from freedom of head movement, good visibility in all directions, and easier use of the feet while moving through stationary traffic. However, high speeds in this position leads to strain on the wrists, uneven roads lead to strain on the back, and extra exposure to the wind leads to both higher fuel consumption and a higher wind-chill factor. Many of these motorcycles now have some form of full fairing and will often come with panniers as OEM.
Cruiser - the rider sits at a lower seat-height with the upper torso upright or leaning slightly rearwards. Legs are extended forwards, sometimes out of reach of the regular controls on cruiser pegs. This position may suit older riders better, allowing more comfortable circulation in the legs. High speeds are not really practical, and it is difficult for the rider to rise from the seat on encountering speed bumps and other road imperfections. This position was traditionally associated with extended or “raked” front forks but these were not particularly stable at speed and led to bigger turning circles. In some cases they were inadequately stiff and strong. These models may have windscreens but are less likely to have fairings or enclosure.
Important factors of a motorcycle's ergonomic geometry that determine the seating posture include the height, angle and location of footpegs, seat and handlebars. Likewise, factors in a rider's physical geometry that contribute to seating posture include torso, arm, thigh and leg length, and overall rider height.
Legal definitions and restrictions
A motorcycle is broadly defined by law in most countries for the purposes of registration, taxation and rider licensing as a powered two-wheel motor vehicle. For riding a motorcycle in Thailand the rider much hold a Thai Drivers license or International Drivers license.