1. INTRODUCTION

1.1 MOPED

Mopeds are motor vehicles that fall somewhere between full-sized motorcycles and

motor-driven bicycles. Unlike traditional motorcycles, mopeds still contain pedals,

hence the name "moped," which stands for "motor/pedal." Mopeds are classified

differently by various governments and municipalities, but must usually be low-

powered vehicles.

1.1.1 Development

Some of the earliest European automobile manufacturers and engine builders

experimented with motor-driven bicycles. These vehicles served as the earliest

motorcycles, but some retained their pedals and small engines, becoming the modern

moped. By using pedals, early mopeds could be driven even when the engine wasn't

powerful enough, such as on uphill climbs. This feature actually gave early mopeds

an advantage over pure motorcycles, but the invention of more powerful motorcycle

engines distinctly separated the two types of vehicles in the early 20th century.

1.1.2 Modern History

The popularity of mopeds has been occasionally boosted by the ever-rising cost of

gasoline. Coupled with the price of cars and motorcycles, this means that mopeds

provide a low-cost form of personal transportation. In many parts of Europe, laws

allow young drivers to operate mopeds on public roads even if they do not meet age

requirements for a vehicle or motorcycle driver's license. This has led mopeds to

become a symbol of youth culture. Mopeds have also been adapted to several other

types of vehicles, including scooters and minibikes.

1.1.3 Operation

Traditional mopeds resemble bicycles and contain one or more motors that connect to

the driveline to provide power. The engines can be mounted anywhere, most often

appearing on the handlebars, below the seat or in front of the rear wheel. A gas tank is

also required, along with a transmission and engine controls for the driver. When the

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engine is started, a moped can be driven in much the same way as a motorcycle with

the driver shifting through gears, and controlling speed and acceleration with a

throttle. The pedals may be used to augment the engine's power output, or when the

engine is disengaged.

1.1.4 Evolution of Terminology

Over time, the definition of a moped has been changed by different users. A variety of

vehicles have been referred to as mopeds. This includes vehicles with such non-

traditional features as three wheels instead of two, more powerful four-stroke engines

(like those used on small motorcycles), continuously variable (shiftless) transmissions

and a lack of pedals for supplying manual power. In the United States, motor scooters

(which utilize an open, step-through frame) are sometimes lumped into the moped

category.

1.1.5 Moped Hybrids

In a strict sense, all traditional mopeds are hybrid vehicles, receiving power from a

combination of manual pedals and the onboard gas engine. Recently, however, a new

class of hybrid electric mopeds have begun to appear, mimicking the trend in car

design by offering an electric motor that can store energy in batteries during braking

or when coasting downhill and later use it to power the vehicle. Hybrid electric

mopeds are generally more expensive than their gas-powered counterparts, often

priced between $2,000 and $3,000 compared to a standard moped's $1,000 to $2,000

price tag. However, these hybrid models require even less fuel, making them more

economical over time.

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2. LITERATURE RIVEW

2.1 HISTORY OF MOPED

This 1912 Douglas has modern chain-drive but still benefits from pedals. The

term "moped" now only applies to low power (often super-economy) vehicles, but

pedals were a sign of sophistication when first fitted to the early motorcycles, such as

the 1912 Douglas in the photograph. Pedalling away from stationary was a great

improvement over "run and jump" and LPA (light pedal assistance) was valuable for

climbing hills. Better transmissions with wider ranges, better clutches and much better

engine performance made pedals obsolete on all serious motorcycles by 1918 but the

pedals on mopeds remained valuable for their original purposes as late as the 1960s.

The earliest mopeds were bicycles with a helper motor in various locations,

for example on top of the front wheel; they were also called cyclemotors. An example

of that type is the VéloSoleX brand, which simply has a roller driving the front tire.

A French VéloSoleX moped. A more innovative design was known in the UK

as the Cyclemaster. This had a complete powered rear wheel which was simply

substituted for the bicycle rear wheel, which originated from a design by two DKW

engineers in Germany. Slightly larger machines, commonly with a 98 cc (6.0 cu in)

engine were known as autocycles. On the other hand some mopeds, such as the

Czech-made Jawa, were derived from motorcycles.

A further category of low-powered two-wheelers exists today in some jurisdictions

for bicycles with helper motors – these are often defined as power-assisted bicycles or

motorized bicycles; see full article there. Other jurisdictions may categorize the same

machines as mopeds, creating a certain amount of confusion. In many countries three

wheelers and microcars are classified as mopeds or variations thereof. This practise is

not restricted to the third-world, France and Belgium classify microcars such as the

Aixam similarly or as "light quadricycles".

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2.2 MOPEDS: HOW DO THEY WORK?

Electric-Powered Moped Mopeds are basically any two-wheeled vehicles. Sometimes

mopeds are also referred to as scooters. Mopeds work via a small capacity engine that

is either powered by gas or electric with restricting speeds between 18 and 53 mph.

However, mopeds generally do not exceed 30 mph if they are to legally be considered

mopeds. Although mopeds are very similar to scooters, they do not perform like

scooters due to the difference in speed, acceleration and model type. Mopeds are

much slower than scooters. Scooters are generally very effective in achieving a higher

top speed and better acceleration than mopeds. This is because of how mopeds are

designed, due to engine displacement and transmission selection. Mopeds run on a

tiny two-stroke engine. Two-stroke engines do not have valves. This allows their

structure to be simplified. Two-stroke engines fire once every time there is a

revolution or rotation of the crankshaft in comparison to the four-stroke engine that

fires once with every other revolution. Therefore, two-stroke engines possess the

potential to package approximately two times the power into the same space

compared to a four-stroke engine. The power of the two-stroke engine in a moped

allows the moped engine to produce a significantly greater boost in power.

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2.3 MOPED OR SCOOTER?

A moped, sometimes called a "scooter," is a motor vehicle with the engine as an

integral part of the vehicle. If the engine is an add-on it's likely the vehicle is a motor

bicycle, which has limited operation on highways different from motorcycles and

mopeds. A moped engine may not exceed 50 cubic centimeters (CCs) in size with an

automatic transmission, or 130 CCs in size if it is a bicycle type vehicle with fully

operative pedals for propulsion by human power.

Traditionally, mopeds had fully operative pedals but modern mopeds are usually more

like small motorcycles with an automatic transmission and no pedals.

2.4 Differences between a moped and a motorized scooter

A motorized scooter is similar to a traditional foot-propelled scooter with two small

wheels except it is powered by either an electric motor or gasoline engine. A person

operating a motorized scooter typically is in the standing position although some

scooters are equipped with a bicycle seat.

Unlike mopeds, which may be driven legally on public roads, a motorized scooter

may not be operated legally on public roads or sidewalks within a roadway’s right-of-

way.

Motorized scooters do not meet federal safety equipment standards for motor vehicles

and are not designed for operation on roadways. Therefore, the law treats motorized

scooters like lawn tractors, all-terrain vehicles, go-carts, mini-bikes and other off-road

motor vehicles that are not allowed on public roads.

In addition, anyone operating a motorized scooter on a street or sidewalk without a

valid driver’s license could receive a citation for operating a motor vehicle without a

driver’s license. For juveniles, such a violation could result in their being ineligible

for a driver’s license when they turn age 16.

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2.5 DUAL LINKAGE COUPLING MECHANISM FOR A MOPED

1. In a moped having a motor, a rear wheel, a rotatable pedal crank including an axle

carrying pinion gear means rotatable with said crank axle for drivingly coupling the

axle with the rear wheel, and a pulley, driven by the motor, for rotation about the axle,

a coupling mechanism for selectively coupling the pulley with the pinion gear means,

comprising:

a first lever having first and second ends, said first end being pivotably connected to

said pulley, said first lever including means, disposed between said first and second

ends, for selectively engaging said pinion gear means to whereby selectively lock the

pulley to the pinion gear means;

a second lever having first and second ends, said second lever being pivotably

connected to said pulley, said first end of said second lever including a nose portion

for selective engagement with said pinion gear means, the second ends of said first

and second levers being pivotably interconnected to each other; and actuating means,

rotatably connected to said pulley and connected to said second lever, said actuating

means including means for moving said coupling mechanism,

(1) from a first position in which said first lever engaging means and said second

lever nose portion are disengaged from said pinion gear means,

(2) to a second position in which said first lever engaging means is disengaged from

said pinion gear means and said second lever nose portion is engaged with said pinion

gear means, and then

(3) to a third position in which said first lever engaging means is engaged with said

pinion gear means and said second lever nose portion is disengaged from said pinion

gear means, whereby said coupling mechanism smoothly, efficiently and positively

couples said engine with said back wheel.

2. The coupling mechanism of claim 1, wherein said pinion gear means comprises

first and second pinion gears disposed in parallel, side-by-side relationship, the first

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gear being coupled to said rear wheel and the second gear being engaged by the nose

portion of said second lever.

3. The coupling mechanism of claim 2, wherein said first lever engaging means

comprises a notch for mating engagement with at least one tooth of said second pinion

gear.

4. The coupling mechanism of claim 1, wherein said pulley carries a first pivot about

which said actuating means is rotatably mounted, and includes slot means disposed

about said first pivot, said actuating means including a pin extending through said slot

means and being connected to said second lever, whereby upon rotation of said

actuating means about said first pivot, said nose portion of said second lever is guided

by the geometry of said slot means into the first, second and third positions.

5. The coupling mechanism of claim 4, wherein said slot means defines a

substantially semi-circular slot positioned concentrically about said first pivot, and

said pin is disposed eccentrically about said first pivot.

6. The coupling mechanism of claim 4, wherein said pulley carries a second pivot,

said first lever first end being pivotally connected about said second pivot, said first

and second pivots being located on opposite sides of said crank axle, and defining

with said axle an imaginary diametrically extending line, said pin being disposed on

said imaginary line when said nose portion is in engagement with said pinion gear

means.

2.6 FIELD OF THE INVENTION

This invention relates to a coupling device between the drive part and cycle part of a

moped.

2.7 BACKGROUND OF THE INVENTION

More particularly, this device is of the type of those known to the prior art, in which

the axle of the crank drive is provided with a stationary pinion, connected by an

endless chain, to the free-wheel pinion secured to the back wheel of the moped for

driving this wheel by pedaling. Furthermore, the axle of the crank drive freely passes

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through the hub of a pulley, having a trapezoidal groove, which is connected by an

endless belt to a drive pulley driven by the engine. The device further includes a hub,

on which is mounted to freely rotate, a double pinion, one of the gears of which is

engaged with an endless chain connecting it to a gear which is integral with the back

wheel of the moped and another gear of which works in conjunction with a

mechanism carried by said grooved pulley, thus making it possible, at will, to connect

or disconnect this pulley with said double pinion.

2.8 OBJECTS AND SUMMARY OF THE INVENTION

The function of this device, generally described above, is to achieve a reducing relay

in the transmission between the engine and the back wheel of the moped and also to

permit coupling or uncoupling between the engine and the back wheel, particularly to

permit driving of the moped merely by pedaling or free-wheeling.

The mechanism carried by the grooved pulley, which permits connection or

disconnecting of the pulley with the second gear of the double pinion, in some cases,

constitutes a double lever. The lever comprises an element, which is articulated on the

pulley and includes a catch functioning to engage with at least one tooth of the

gearing of the double pinion. The lever further comprises another element, articulated

at the end of the first, which other element articulates with an eccentric element

controlled by a control button mounted to turn on the pulley and placed on the outside

of the latter.

By making this button pivot, the user can move the double lever between a first

locked position, in which, for example, the two catches, provided on one of the levers,

engage with one or two teeth of the second gearing of the double pinion, and a second

unlocked position. In the unlocked position the catches of the lever are separated from

this gearing, which obviously serves to uncouple the engine from the back wheel of

the moped.

During maneuvering of the control button, which functions to make the coupling

device move from the unlocked position to the locked position, interlocking can be

difficult or uncertain if the catches of the lever are not brought exactly opposite the

complementary notches existing between the teeth of the double pinion. It is therefore

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an object of the invention to improve the operation of this known coupling device to

permit easy and sure interlocking of the catch or catches of the locking lever with the

second gearing of the double pinion because of automatic preselection of the

positioning of this pinion.

The two elements of the double lever, being respectively designated below by the

expressions "locking lever" and "control lever," function to achieve the essential

characteristic of the device. Accordingly, an object of the invention resides in the fact

that the control lever is structured to comprise a nose generally turned toward the

crank axle and which, in the locking or unlocking position of the device, is located in

withdrawn position in relation to the second gearing of the double pinion. When the

locking lever is, by its notch or notches, either engaged or disengaged with said

gearing, this nose, on the other hand, momentarily engages with said gearing when the

control button is turned from the unlocking position to the locking position and

causes, during this momentary engagement, a rotational movement of the double

pinion around the hub of the pulley so that the meshing tooth or teeth of the second

gearing are brought exactly opposite the catch or catches of the locking lever.

The above-described device facilitates the engagement of the catches of the locking

lever with the second gearing of the double pinion utilizing extremely simple means

since neither the double pinion, the control button nor the locking lever are modified.

The only addition to the device structure consists of a nose that can be made integral

with the control lever and, of course, would be correctly dimensioned and positioned

to engage momentarily with the second gearing of the double pinion and to bring this

latter mechanism exactly into the desired position.

In a particular embodiment of the invention, this control lever is extended beyond its

articulation point on the eccentric element, which is linked to the control button, the

projecting nose of the control lever having a generally bent shape.

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3. SYSTEM MODELING

3.1 KINETIC LUNA TFR PLUS MOPED

The LUNA TFR  PLUS is a good moped which is well performed on the road

with light weight and it was most liked by women.It was nicely designed  keeping in

mind that the scooter is mainly for city ride  and it got success too .Its a pedal start

like bicycle If it got some problem in engine you can pedal it this is the one plus point

here.its a 50 cc moped which is good in pick up, given a good mileage , well suited

for cities and its a reasonable too.The maximum speed given by the company is

60kmpl.This TFR plus was simple and attractive styled moped.It gives a mileage on

an avg of 65kmpl in city.The 50 cc engine is air cooled auto uni ratio belt drive which

perform well on road.Telescopic suspension for comfortable riding, very good in

handling and braking.

Kinetic TFR Plus is the first moped in India. Its low maintenance cost and other

salient features has approached to the heart of the million moped buyers. Luna TFR

Its 49.8 cc engines delivers maximum output of 1.67 HP @ 4500 + 500 rpm and

maximum torque of 2.9 Nm @ 3000 rpm. Its stylish body lining and appealing colors

are one of those striking features which are making this moped choice of the buyers.

Its strong chassis, decompression lever for easy pedal start, larger fuel tank etc. have

made this moped more market friendly.

The moped has stylish body lining and appealing colors which helps end users to

make Kinetic Luna their choice. Salient features of Kinetic Luna include Kick start,

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Rugged boxed steel body in black and shiny chrome, light weight, easy to handle and

pedal kick start.

Mopeds can achieve fuel economy of over 100 mpg. The emissions of mopeds have

been the subject of multiple studies. Studies have found that 2 stroke 50cc mopeds,

with and without catalytic converters, emit 10 to 30 times the hydrocarbons and

particulate emissions than the outdated Euro 3 automobile standards. Approximate

parity with automobiles was achieved with CO and NOx emissions in these studies.

Emissions performance was tested on a g/km basis and was unaffected by fuel

economy. An additional air quality challenge can also arise from the use of 2-stroke

transportation over automobiles, as a higher density of motorized vehicles can be

supported by existing transportation infrastructure.

FIG. 3.1 LUNA TFR

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3.2 SPECIFICATION

Make: Kinetic

Model : Luna Tfr

Cc : 49.8 Cc

Power :1.75 @ 5000 Rpm

Torque :2.94 @ 3000 Rpm

Engine Type : Air Cooled

Bore :38.4 Mm

Stroke : 43 Mm

Starter : Pedal Start

Length :1650 Mm

Height : 1030 Mm

Gear : Uni Ratio Belt Drive

Mileage : 65 Kmpl

Tank  : 2.5 Lts

VEHICLE SUMMARY

Name: Luna

Model: TFR Plus

Type: Scooterette

ENGINE SPECIFICATIONS

Displacement: 49.8cc

Engine: Air Cooled

OTHER SPECIFICATIONS

Ground Clearance: 120.00 mm

Wheelbase: 1100.00 mm

Electrical System: NA

Headlamp: NA

Horn: NA

Tubeless:

Colors: NA

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Maximum Power: 1.25bhp@4500rpm

Maximum Torque: 2.943Nm@3000rpm

Gears: Automatic

Clutch: NA

Bore: NA

Stroke: NA

Cylinder

Configuration:NA

Engine Block

Material:NA

Chassis Type: NA

Carburetor: NA

DIMENSIONS

Length: N/A

Width: N/A

Height: N/A

ACTIVE AND PASSIVE SAFETY

Suspension(Front): NA

Suspension(Rear): NA

Brakes: NA

Brakes(Rear): NA

Stand Alarm:

COMFORT AND CONVENIENCE

Self Start:

Alloys:

Warranty: NA

Passenger Footrest:

Passenger Backrest:

Step-up Seat:

Pass-light:

Low Fuel Indicator:

Low Oil Indicator:

Low Battery Indicator:

High Oil Temp. Indicator:

Choked Air Filter Indicator:

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3.3 VARIATION

. Luna TFR Plus Luna Superstar

Type

Bore

Stroke

No. Of Cylinders

Displacement (Cc)

Compression Ratio

A. Max. Engine Output (Kw)

B. Max. Engine Output (Hp)

Max. Torque (Nm)

Air Cleaner

Oil Sump Capacity

Weight Of Engine (Kg.)

Wheel Base ( Mm )

Overall Width (Mm)

Overall Length (Mm)

Max. Gvw (Kg.)

Min. Ground Clearance

Two wheeler

38.4 mm

43 mm

One horizontal

49.8 cc

8.0:1 ( + 0.5)

1.25 + 0.06 KW

@ 4500 + 500 rpm

1.67

2.943 @ 3000 rpm

Wire mesh

N.A.

7.5

1100

630

1650

170

120

Two wheeler

42 mm

43 mm

One

59.57 cc

8.8:1(+ 0.2)

2.2 + 0.1 KW

@6000 + 250 rpm

2.94

4.2 @ 4000 rpm

Wire mesh

N.A.

12.5

1130

660

1805

184

180

Tyre Size

Front

Rear

2.25" X 16"

2.25" X 16" - 6 ply

2.5" X 16 - 4 ply

2.5" X 16 - 6 ply

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4. PERFORMANCE ANALYSIS

4.1 THE TWO-STROKE ENGINE

Couldn't an engine be constructed, that needs less than four strokes and that performs

the same power as the Otto engine? Couldn't you reduce or even replace the

complicated valve mechanics? These questions led to the development of the two-

stroke otto engine. It needs only one revolution of the crankshaft to indicate a new

ignition. Additionally, the piston has at the same time the function of a valve, which

saves many mobile parts: The two-stroke engine consists of only three mobile parts:

Piston, connecting rod and crankshaft. Let's have a look at the mode of operation of

this engine:

4.2 Mode of operation of the two-stroke engine

1st stroke: The piston is at the bottom of the cylinder. A pipe at the left side is

opened and lets the fuel mixture, which is already compressed a bit, flow from the

lower to the upper part of the cylinder. The fresh gases expulse now the exhaust

through an ejection pipe, which is not closed by the piston at this moment.

2nd stroke: After being hurried upward, the piston now covers the pipe on the left

side and the ejection pipe. Because there is no way out any more, the upper, fresh gas

mixture gets compressed now. At the same time in the part below fresh gas is taken in

by the piston driving upward through the open suction pipe. At the upper dead-center,

the compressed fuel mixture is ignited by the sparking plug, the piston is pressed

downward while he compresses at the same time the fresh gas below. The process

begins again as soon as the piston arrives at its lowest point.

Development

The idea to build a two-stroke engine goes back to the year 1879. But this engine

became a qualitatively good product only after many years, when the German DKW

company accelerated its development. Because of its disadvantages compared with

the four-stroke engine, the two-stroke engine is used practically just in a small range

of capacity,

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4.3 THE COMPRESSION STROKE

Now the momentum in the crankshaft starts driving the piston back toward the spark

plug for the compression stroke. As the air/fuel mixture in the piston is compressed, a

vacuum is created in the crankcase. This vacuum opens the reed valve and sucks

air/fuel/oil in from the carburetor.

Once the piston makes it to the end of the compression stroke, the spark plug fires

again to repeat the cycle. It's called a two-stoke engine because there is a compression

stroke and then a combustion stroke. In a four-stroke engine, there are separate intake,

compression, combustion and exhaust strokes.

On one side of the piston is the combustion chamber, where the piston is compressing

the air/fuel mixture and capturing the energy released by the ignition of the fuel.

On the other side of the piston is the crankcase, where the piston is creating a vacuum

to suck in air/fuel from the carburetor through the reed valve and then pressurizing the

crankcase so that air/fuel is forced into the combustion chamber.

Meanwhile, the sides of the piston are acting like valves, covering and uncovering the

intake and exhaust ports drilled into the side of the cylinder wall.

It's really pretty neat to see the piston doing so many different things! That's what

makes two-stroke engines so simple and lightweight. If you have ever used a two-

stroke engine, you know that you have to mix special two-stroke oil in with the

gasoline. Now that you understand the two-stroke cycle you can see why. In a four-

stroke engine, the crankcase is completely separate from the combustion chamber, so

you can fill the crankcase with heavy oil to lubricate the crankshaft bearings, the

bearings on either end of the piston's connecting rod and the cylinder wall. In a two-

stroke engine, on the other hand, the crankcase is serving as a pressurization chamber

to force air/fuel into the cylinder, so it can't hold a thick oil. Instead, you mix oil in

with the gas to lubricate the crankshaft, connecting rod and cylinder walls.

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4.4 PROBLEMS OF THE TWO-STROKE ENGINE

Actually the two-stroke engine should perform twice the performance of a four-stroke

engine with the same cubic capacity. Though it is just possible to gain a performance

that is about 50% better. The reasons are obvious: The cylinder can't be filled up with

the same amount of fuel as in the four-stroke engine, because the individual strokes

are seperated not so clearly. If more fuel is induced, it leaves the combustion chamber

through the ejection pipe without being burnt. Many concepts were developed to

provide a better expulsion of the exhaust in way that the fresh gas doesn't leave the

combustion chamber (as for example the "nosepiston" you can see in the animation

above, which causes turbulences of a certain type). Though all these inventions, the

filling of the two-stroke engine is always worse than in the four-stroke engine, which

loses fresh fuel only because of the "overlap" of the valve times (both valves are open

for an instant). Beside these performance-technical problems, there are also increasing

difficulties with the environment. The fuel mixture of the two-stroke engine often gets

shifted with a certain quantity of oil because of the necessary lubrication.

Unfortunately the oil gets burnt partly, too, and harmful gases are expulsed by the

engine.

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4.5 TWO-STROKE BASICS

This is what a two-stroke engine looks like:

You find two-stroke engines in such devices as chain saws and jet skis because two-

stroke engines have three important advantages over four-stroke engines:

FIG 4.1 TWO STROKE BASICS

Two-stroke engines do not have valves, which simplifies their construction and

lowers their weight.

Two-stroke engines fire once every revolution, while four-stroke engines fire once

every other revolution. This gives two-stroke engines a significant power boost.

Two-stroke engines can work in any orientation, which can be important in something

like a chainsaw. A standard four-stroke engine may have problems with oil flow

unless it is upright, and solving this problem can add complexity to the engine.

These advantages make two-stroke engines lighter, simpler and less expensive to

manufacture. Two-stroke engines also have the potential to pack about twice the

power into the same space because there are twice as many power strokes per

revolution. The combination of light weight and twice the power gives two-stroke

engines a great power-to-weight ratio compared to many four-stroke engine designs.

4.5.1 The Two-stroke Cycle

The following animation shows a two-stroke engine in action. You can compare this

animation to the animations in the car engine and diesel engine articles to see the

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differences. The biggest difference to notice when comparing figures is that the spark-

plug fires once every revolution in a two-stroke engine.

4.5.2 Sparks Fly

You can understand a two-stroke engine by watching each part of the cycle. Start with

the point where the spark plug fires. Fuel and air in the cylinder have been

compressed, and when the spark plug fires the mixture ignites. The resulting

explosion drives the piston downward. Note that as the piston moves downward, it is

compressing the air/fuel mixture in the crankcase. As the piston approaches the

bottom of its stroke, the exhaust port is uncovered.

4.5.3 Fuel Intake

As the piston finally bottoms out, the intake port is uncovered. The piston's movement

has pressurized the mixture in the crankcase, so it rushes into the cylinder, displacing

the remaining exhaust gases and filling the cylinder with a fresh charge of fuel.

4.5.4 The Compression Stroke

Now the momentum in the crankshaft starts driving the piston back toward the spark

plug for the compression stroke. As the air/fuel mixture in the piston is compressed, a

vacuum is created in the crankcase. This vacuum opens the reed valve and sucks

air/fuel/oil in from the carburetor.

Once the piston makes it to the end of the compression stroke, the spark plug fires

again to repeat the cycle. It's called a two-stoke engine because there is a compression

stroke and then a combustion stroke. In a four-stroke engine, there are separate intake,

compression, combustion and exhaust strokes.

You can see that the piston is really doing three different things in a two-stroke

engine:

On one side of the piston is the combustion chamber, where the piston is compressing

the air/fuel mixture and capturing the energy released by the ignition of the fuel.

On the other side of the piston is the crankcase, where the piston is creating a vacuum

to suck in air/fuel from the carburetor through the reed valve and then pressurizing the

crankcase so that air/fuel is forced into the combustion chamber.

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Meanwhile, the sides of the piston are acting like valves, covering and uncovering the

intake and exhaust ports drilled into the side of the cylinder wall.

It's really pretty neat to see the piston doing so many different things! That's what

makes two-stroke engines so simple and lightweight.

If you have ever used a two-stroke engine, you know that you have to mix special

two-stroke oil in with the gasoline. Now that you understand the two-stroke cycle you

can see why. In a four-stroke engine, the crankcase is completely separate from the

combustion chamber, so you can fill the crankcase with heavy oil to lubricate the

crankshaft bearings, the bearings on either end of the piston's connecting rod and the

cylinder wall. In a two-stroke engine, on the other hand, the crankcase is serving as a

pressurization chamber to force air/fuel into the cylinder, so it can't hold a thick oil.

Instead, you mix oil in with the gas to lubricate the crankshaft, connecting rod and

cylinder walls. If you forget to mix in the oil, the engine isn't going to last very long!

4.6 Disadvantages of the Two-stroke

You can now see that two-stroke engines have two important advantages over four-

stroke engines: They are simpler and lighter, and they produce about twice as much

power. So why do cars and trucks use four-stroke engines? There are four main

reasons:

Two-stroke engines don't last nearly as long as four-stroke engines. The lack of a

dedicated lubrication system means that the parts of a two-stroke engine wear a lot

faster.

Two-stroke oil is expensive, and you need about 4 ounces of it per gallon of gas. You

would burn about a gallon of oil every 1,000 miles if you used a two-stroke engine in

a car.

Two-stroke engines do not use fuel efficiently, so you would get fewer miles per

gallon.

Two-stroke engines produce a lot of pollution -- so much, in fact, that it is likely that

you won't see them around too much longer.

The pollution comes from two sources. The first is the combustion of the oil. The oil

makes all two-stroke engines smoky to some extent, and a badly worn two-stroke

engine can emit huge clouds of oily smoke.

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4.7 IGNITION & ELECTRICS

Mount the Kill Switch and Ignition module where their wires will reach those coming

from the engine (again – don’t over-tighten things). Hook up the two black wires

coming from the ignition module and the engine. Hookup the green/blue wire from

the ignition module with the blue wire from the engine – AND the black/red wire

from the kill switch (mounted up on the handlebar by the throttle). The other black

wire from the throttle kill switch will need to connect to the frame of the bicycle for a

ground. Install the spark plug and the plug wire (unscrew and discard the little cap on

the top of the plug). The white wire coming from the engine is the electrical output of

the motor’s generator: 7.5 volts at 0.5 amp. DO NOT hookup the white wire to

anything other that whatever electrical gadget(s) you may have. Remember that

exceeding 3.75 watts (7.5V x 0.5@) will kill the engine – so be sparing with your

electrical demands.

4.8 Magnato

A magneto is an electrical generator that uses permanent magnets to produce

alternating current. Hand-cranked magneto generators were used to provide ringing

current in early telephone systems. Magnetos adapted to produce pulses of high

voltage are used in the ignition systems of some gasoline-powered internal

combustion engines to provide power to the spark plugs. The magneto is now

confined mainly to engines where there is no available electrical supply, for example

in lawnmowers and chainsaws. It is also universally used in aviation piston engines

even though an electrical supply is usually available. This is because a magneto

ignition system is more reliable than a battery-coil system. People discussing

magnetos and coils used in early internal-combustion engines generally used the term

"tension" instead of the more modern term "voltage."

Production of electric current from a moving magnetic field was demonstrated by

Faraday in 1831. The first machines to produce electric current from magnetism used

permanent magnets; the dynamo machine, which used an electromagnet to produce

the magnetic field, was developed later. The machine build by Hippolyte Pixii in 1832

used a rotating permanent magnet to induce alternating voltage in two fixed coils.

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The first person to develop the idea of a high-tension magneto was Andre Boudeville,

but his design omitted a condenser (capacitor); Frederick Richard Simms in

partnership with Robert Bosch were the first to develop a practicable high-tension

magneto.

Magneto ignition was introduced on the 1899 Daimler Phönix. This was followed by

Benz, Mors, Turcat-Mery, and Nesseldorf, and soon was used on most cars up until

about 1918 in both low voltage (voltage for secondary coils to fire the spark plugs)

and high voltage magnetos (to fire the spark plug directly, similar to coil ignitions,

introduced by Bosch in 1903).

The magneto also had a medical use on some mind illness in the beginnings of

electromedicine. In 1850, Duchenne, a French doctor, developed and manufactured a

magneto with a variable outer voltage and frequency, through varying revolutions by

hand or varying the inductance of the two coils, putting out or putting in both

ferromagnetic cores.

One popular and common use of magnetos of today is for powering lights on bicycles.

A small magneto is mounted on the wheel of the bicycle and generates power as the

wheel turns.

4.9 Operation

In the type known as a shuttle magneto, the engine rotates a coil of wire between the

poles of a magnet. In the inductor magneto, the magnet is rotated and the coil remains

stationary.

On each revolution, a cam opens the contact breaker one or more times, interrupting

the current, which causes the electromagnetic field in the primary coil to collapse. As

the field collapses there is a voltage induced (as described by Faraday's Law) across

the primary coil. As the points open, point spacing is such that the voltage across the

primary coil would arc across the points. A capacitor is placed across the points which

absorbs the energy stored in the primary coil. The capacitor and the coil together form

a resonant circuit which allows the energy to oscillate from the capacitor to the coil

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and back again. Due to the inevitable losses in the system, this oscillation decays

fairly rapidly.

A second coil, with many more turns than the primary, is wound on the same iron

core to form an electrical transformer. The ratio of turns in the secondary winding to

the number of turns in the primary winding, is called the turns ratio. Voltage across

the primary coil results in a proportional voltage being induced across the secondary

winding of the coil. The turns ratio between the primary and secondary coil is selected

so that the voltage across the secondary reaches a very high value, enough to arc

across the gap of the spark plug.

In a modern installation, the magneto only has a single low tension winding which is

connected to an external ignition coil which not only has a low tension winding, but

also a secondary winding of many thousands of turns to deliver the high voltage

required for the spark plug(s). Such a system is known as an "energy transfer" ignition

system. Initially this was done because it was easier to provide good insulation for the

secondary winding of an external coil than it was in a coil buried in the construction

of the magneto (early magnetos had the coil assembly externally to the rotating parts

to make them easier to insulate - at the expense of efficiency). In more modern times,

insulation materials have improved to the point where constructing self contained

magnetos is relatively easy, but energy transfer systems are still used where the

ultimate in reliability is required such as in aviation engines.

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FIG 4.2 IGNITION

4.9. Battery-operated ignition

With the universal adaptation of electrical starting for automobiles, and the

concomitant availability of a large battery to provide a constant source of electricity,

magneto systems were abandoned for systems which interrupted current at battery

voltage, used an ignition coil (a type of autotransformer) to step the voltage up to the

needs of the ignition, and a distributor to route the ensuing pulse to the correct spark

plug at the correct time.

The first reliable battery operated ignition was developed by the Dayton Engineering

Laboratories Co. (Delco) and introduced in the 1910 Cadillac. This ignition was

developed by Charles Kettering and was a wonder in its day. It consisted of a single

coil, points (the switch), a capacitor and a distributor set up to allocate the spark from

the ignition coil timed to the correct cylinder. The coil was basically an

autotransformer set up to step up the low (6 or 12 V) voltage supply to the high

ignition voltage required to jump a spark plug gap.

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The points allow the coil to charge magnetically and then, when they are opened by a

cam arrangement, the magnetic field collapses and a large (20 kV or greater) voltage

is produced. The capacitor is used to absorb the back EMF from the magnetic field in

the coil to minimize point contact burning and maximize point life. The Kettering

system became the primary ignition system for many years in the automotive industry

due to its lower cost, higher reliability and relative simplicity.

FIG 4.3 LUNA TFR ENGINE

FIG 4.4 CHAIN SPROCKET

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FIG 4.5 ENGINE DRIVE

FIG 4.6 THROTTLE SWITCH

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Kinetic TFR/Luna moped engine piston and rings

Kinetic TFR/Luna moped clutch 3 bottom washers

Kinetic TFR/Luna moped throttle lever

Kinetic TFR/Luna moped front wheel

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Kinetic TFR/Luna moped decompression lever

Kinetic TFR/Luna moped air box intake valve

Kinetic TFR/Luna moped front wheel

Kinetic TFR/Luna moped engine cylinder cover

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Kinetic TFR/Luna moped lower frame assembly

Kinetic TFR/Luna moped clutch inner clutch shoe

Kinetic TFR/Luna moped brake cable adjuster

Kinetic TFR/Luna moped handlebar mounting bracket

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FIG 4.7 ENGINE CASTING

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5. CONCLUSION

Since its inception, Luna has been known for the convenient ride and negligible

maintenance cost. It served as a ubiquitous mode of transportation in rural Indian

hinterland. Over the years, the Luna has undergone changes so as to keep pace with

the changing times. Its strong chassis, decompression lever for easy pedal start, larger

fuel tank etc. have made the moped more user friendly. Extra footrest in front helps

one to sit comfortably on it. TPFC boosts enhanced acceleration and sturdy body of

course helps it in cruising on rural roads.

Its wheel base provides firm grip on the road and the brake system and all other safety

features give the assurance of secured riding. Telescopic suspension adds to the

efficiency of the vehicle. Front and rear drum brakes are effective in bringing the

vehicle to a halt.

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REFERENCE

www.indianauto.com/bikes1/kinetic-engineering/luna.htm

www.infibeam.com › ... › Kinetic Bikes › Kinetic Luna

autos.maxabout.com/twid0000100/kinetic_luna_tfr_plus.aspx

www.letsknow.info/bikes/luna-tfr-plus-price/

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