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1. Introduction:
Suspension is the term given to the system of springs, shock absorbers and linkages that connects a vehicle to its wheels. Suspension systems serve a dual purpose — contributing to the car's roadholding/handling and braking for good active safety and driving pleasure, and keeping vehicle occupants comfortable and reasonably well isolated from road noise, bumps, and vibrations,etc. These goals are generally at odds, so the tuning of suspensions involves finding the right compromise. It is important for the suspension to keep the road wheel in contact with the road surface as much as possible, because all the forces acting on the vehicle do so through the contact patches of the tires. The suspension also protects the vehicle itself and any cargo or luggage from damage and wear. The design of front and rear suspension of a car may be different.Automobile suspensions have many variable characteristics, which are generally different in the front and rear and all of which affect handling. Some of these are:
spring rate, damping, straight ahead camber angle, camber change with wheel travel, roll center height and the flexibility and vibration modes of the suspension elements. Suspension also affects unsprung weight.
A motorcycle’s suspension is similar toThe suspension in an automobile in its purpose:“Suspension system serve a dual purpose-contributing to the vehicle’s handling and breaking for good active safety and driving pleasure, & keeping vehicle passangers comfartable & reasonably well isolated from road noise, bumps and vibration.”But a motorcycle suspension is usually simpler,since it does not have to conted with lateral forces such as body roll. The typical motorcycle has a pair of fork tubes for the front suspension,and a single swingwarm with one or two shock absorbers for the rear suspension.
2. Suspension:
A Motorcycle Suspension System consists of a spring coupled to a viscous damping element, a piston, in a cylinder filled with oil. The piston smooths out vibrations induced by the vehicle while moving as it moves through the oil. The flow of oil through the piston is regulated by an adjustable elastic deformable flap called a shim.
Types of Motorcycle Suspension
Front Suspension:
The predominant type of front suspension is the suspension fork. The bottom part of the fork is fitted over the tubes that connect the fork to the frame. When the vehicle hits a bump, the spring
gets compressed and the piston orces fluid through the orifice.
Rear Suspension: Most of the time the rear suspension are used as a shock absorber.Both these two types of suspensions contain two essential elements: a spring and a damper which are collectively referred to as a shock
absorber.
Functions of Motorcycle
Suspension:
The main functions of the motorcycle
suspensions are:
• To insulate both the rider and the bulk of the machine from road shocks. It makes a much safer and comfortable ride and is important for proper mechanical reliability and longevity.
• To keep the wheels in the closest possible contact with the ground and gives control of the vehicle to the rider.
• The front suspension helps to guides the front wheel, to steer, to spring, to dampen, and to provide support under braking.
Materials used for making Suspensions:
The materials most commonly used for making suspensions are:
• Steel
• Aluminum
Maintenance of Suspensions:
• The suspensions should be checked for loose nuts and bolts and leaks.
• The swing arm bearings should be lubricated monthly.
3. Modern Suspension System:
HydraulicFluids:
Hydraulic fluids are liquids used as the motive medium in hydraulic machinery and equipment. These fluids are used in a number of machines including automobiles. Car transmissions, power brakes and power steering systems all require hydraulic fluids. Hydraulic fluids are used in a number of vehicles starting from tractors to garbage lifters. There are many fluids used for hydraulic oil like mineral oil, water, synthetic compounds, and water based mixtures, castor oil, ethers, esters.
4. Suspension(Motorcycle) System:
After the engine of a vehicle it is the suspension system that holds prime importance because it is the harbinger of a comfortable ride. The suspension system minimizes the impact of a particular road condition providing a safe drive to the occupants of the vehicle. This might sound pretty simple but when you come to think of it seriously it is not as simple as it might seem to be. When acceleration comes into force and force translates into raw energy this energy travels through the frame of the vehicle .without coils and springs to absorb this the vertical energy would cause the vehicle to jump up off the road reducing tire friction and control which would result in a heavy bounce back downwards by the car with even greater force which could be very dangerous. Coil spring and leaf springs to absorb all forces and to keep the tires firmly planted to the ground so that the tire always remains in contact with the ground
The term suspension is given to the springs, shock absorbers and linkages that connect a vehicle to its wheels. The suspension system mainly serves the purpose of providing safety to the car by minimizing jerks and provides comfort to the occupants of the vehicle.
Principle of SuspensionSystem:
To restrict road vibrations from being transmitted to the various components of the vehicle To protect the passengers from road shocks To maintain the stability of the vehicle in pitching and rolling.
Components of the Suspension System:
Control Arm: A movable lever that fastens the steering knuckle to the frame of the vehicle.
Control Arm Busing: This is a sleeve which allows the control arm to move up and down on the frame.
Strut Rod: Prevents the control arm from swinging forward and backwards.
Ball Joints: A joint that allows the control arm and steering knuckle to move up and down.
Shock absorbers or Struts: prevents the suspension from bounce after spring compression and extension
Stabilizer Bar: Limits body roll of the vehicle during cornering
Spring: Supports the weight of the vehicle.
Common problems of the suspension system:
Shocks and Struts: Shocks and Struts are located behind the wheels of a vehicle. Shocks and Struts are subject to wear and tear just like other vehicle parts. The signs of a shock wear out are if the car bounces excessively, leans hard in corners and jerks at brakes then the shocks and struts are definitely calling for a change.
Ball joints: The wearing out of ball joints can get dangerous because if they separate they cause you to lose control over the vehicle which could also be a life risk.
Preventive Measures(Motorcycle):
The shocks and struts should be check frequently for leakages
Ball joints should be checked immediately incase the motion of the car is not right.Make sure to lubricate the ball joints of your car frequently.
5. Setting up a suspension:
Many older motorcycles do not offer much in the way of suspension adjustments. Simple pre-load adjustment for the rear shock(s) and nothing more is not uncommon.However, on modern motorcycles with higher specifications both pre-load and compression adjustments are standard, on both front and rear suspension. Some models as of 2006 offer both high and low speed compression adjustment.Even those motorcycles that do offer adjustments sometimes cannot be adjusted far enough for some riders.Properly tuning motorcycle suspension often requires assistance from an expert due to the range of adjustment possible. It is very difficult for the average rider to determine what adjustments need to be made, as a poorly set up rear end may cause front-end problems, and vic e versa.
6. Motorcycle:
A motorcycle (also called a motorbike, bike, or cycle) is a single-track, two-wheeled motor vehicle. 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.Motorcycles are one of the most affordable forms of motorised transport in many parts of the world and, for most of the world's population, they are also the most common type of motor vehicle.There are around 200 million motorcycles in use worldwide,or about 33 motorcycles per 1000 people. This compares to around 590 million cars, or about 91 per 1000 people. Most of the motorcycles, 58%, are in the developing countries of Asia—Southern and Eastern Asia, and the Asia Pacific countries, excluding Japan—while 33% of the cars (195 million) are concentrated in the United States and Japan. As of 2002, India with an estimated 37 million motorcycles/mopeds was home to the largest number of motorised two wheelers in the world. China came a close second with 34 million motorcycles/mopeds.
7. History:
The first internal combustion, petroleum fueled motorcycle was the Petroleum Reitwagen. It was designed and built by the German inventors Gottlieb Daimler and Wilhelm Maybach in Bad Cannstatt, Germany in 1885. This vehicle was unlike either the safety bicycles or the boneshaker bicycles of the era in that it had zero degrees of steering axis angle and no fork offset, and thus did not use the principles of bicycle and motorcycle dynamics developed nearly 70 years earlier. Instead, it relied on two outrigger wheels to remain upright while turning. The inventors called their invention the Reitwagen ("riding car"). It was designed as an expedient testbed for their new engine, rather than a true prototype vehicle. Many authorities who exclude steam powered, electric or diesel two-wheelers from the definition of a motorcycle, credit the Daimler Reitwagen as the world's first motorcycle. If a two-wheeled vehicle with steam propulsion is considered a motorcycle, then the first was the French Michaux-Perreaux steam bicycle of 1868. This was followed by the American Roper steam velocipede of 1869, built by Sylvester Howard Roper of Roxbury, Massachusetts. Roper demonstrated his machine at fairs and circuses in the eastern U.S. in 1867, and built a total of 10 examples. In 1894, Hildebrand & Wolfmüller became the first series production motorcycle, and the first to be called a motorcycle (German: Motorrad). In the early period of motorcycle history, many producers of bicycles adapted their designs to accommodate the new internal combustion engine. As the engines became more powerful and designs outgrew the bicycle origins, the number of motorcycle producers increased.Until World War I, the largest motorcycle manufacturer in the world was Indian, producing over 20,000 bikes per year. By 1920, this honour went to Harley-Davidson, with their motorcycles being sold by dealers in 67 countries. By the late 1920s or early 1930s, DKW took over as the largest manufacturer. After World War II, the BSA Group became the largest producer of motorcycles in the world, producing up to 75,000 bikes per year in the 1950s.The German company NSU held the position of largest manufacturer from 1955 until the 1970s.
NSU Sportmax streamlined motorcycle, 250 cc class winner of the 1955 Grand Prix season.In the 1950s, streamlining began to play an increasing part in the development of racing motorcycles and the "dustbin fairing" held out the possibility of radical changes to motorcycle design. NSU and Moto Guzzi were in the vanguard of this development both producing very radical designs well ahead of their time. NSU produced the most advanced design, but after the deaths of four NSU riders in the 1954–1956 seasons, they abandoned further development and quit Grand Prix motorcycle racing. Moto Guzzi produced competitive race machines, and by 1957 nearly all the Grand Prix races were being won by streamlined machines.
