The Ducati 450 Scrambler, also known in the US as the Ducati Jupiter and in Europe as the Ducati 450 SCR is an on/off-road

single cylinder A single-cylinder engine, sometimes called a thumper, is a piston engine with one cylinder. This engine is often used for motorcycles, motor scooters, go-karts, all-terrain vehicles, radio-controlled vehicles, portable tools and garden machinery ( ...

bevel drive

SOHC An overhead camshaft (OHC) engine is a piston engine where the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustion cha ...

motorcycle produced by the Italian manufacturer

Ducati Ducati Motor Holding S.p.A. () is the motorcycle-manufacturing division of Italian company Ducati, headquartered in Bologna, Italy. The company is directly owned by Italian automotive manufacturer Lamborghini, whose German parent company is Au ...

from 1969 to 1974. Total production was around 11,000 machines. The model was also produced under licence in Spain by

MotoTrans MotoTrans is a Spanish company which produced motorcycles and scooters between 1957 and 1983 when it was bought by Yamaha. MotoTrans was famous for licensing Ducati Ducati Motor Holding S.p.A. () is the motorcycle-manufacturing division of I ...

History

In 1968 the global market for dirt bikes was large. Ducati was already producing

250 __NOTOC__ Year 250 ( CCL) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Traianus and Gratus (or, less frequently, year 1003 ''Ab u ...

and 350 Scramblers but the American importers,

Berliner Motor Corporation Berliner Motor Corporation was the US Distribution (business), distributor from the 1950s through the 1980s for several European motorcycle marques, including Ducati, J-Be, Matchless, Moto Guzzi, Norton Motorcycle Company, Norton, Sachs Motorcycl ...

requested a larger-engined version to compete against the BSA 441 Victor. The 450 Scrambler was introduced in 1969, and was the first model to use the 436 cc engine, which was the largest displacement possible that the OHC engine could be stretched to. The frame, the design of which used input from the racing department, was a strengthened version of that used on the smaller scramblers with gussets along the top tube. The 450 was successfully used in

flat track Dirt track racing is a form of motorsport held on clay or dirt surfaced oval race tracks often used for thoroughbred horse racing. Dirt track racing started in the United States before World War I and became widespread during the 1920s and 1930s ...

, enduro and

scrambles ''Scrambles'' is the fifth studio album by Bomb the Music Industry!, released digitally and physically on February 15th, 2009. The album was released a year and a half after Get Warmer, making it the longest gap between the release of two chrono ...

racing. In 1973 the model gained electronic ignition, a double-sided front brake and the lights and instruments used on the

Mark 3 Mark 3 is the third chapter of the Gospel of Mark in the New Testament of the Christian Bible. It relates a conflict over healing on the Sabbath, the commissioning of the Twelve Apostles, a conflict with scribes and a meeting of Jesus with h ...

. The factory ceased production of OHC singles in 1974. The remaining stocks were purchased by the then British importer Coburn & Hughes, who continued to sell them until early 1976. Amongst these bikes were some 450 Scramblers which were marketed as ''Mark 4'', a reference to the Mark 3 roadsters.

Technical details

Engine and transmission

The single cylinder bevel drive OHC engine was of a vertically spilt

unit construction : ''For the vehicle design where the vehicle's skin is used as a load-bearing element, see Monocoque.'' Unit construction is the design of larger motorcycles where the engine and gearbox components share a single casing. This sometimes includes ...

and had alloy

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may ...

and alloy

barrels A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden staves and bound by wooden or metal hoops. The word vat is often used for large containers for liquids, u ...

with

austenitic Austenite, also known as gamma-phase iron (γ-Fe), is a metallic, non-magnetic allotrope of iron or a solid solution of iron with an alloying element. In plain-carbon steel, austenite exists above the critical eutectoid temperature of 1000 K ...

liners.

Ball bearing A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races. The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this ...

s were used in the main bearings and

roller bearing In mechanical engineering, a rolling-element bearing, also known as a rolling bearing, is a bearing which carries a load by placing rolling elements (such as balls or rollers) between two concentric, grooved rings called races. The relative m ...

s for the big end. Hairspring valve springs were used to close the valves. Bore and stroke were giving a displacement of .

Compression ratio The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values. A fundamental specification for such engines, it is measured two ways: the stati ...

was 9.3:1 and claimed power output was @ 7,000 rpm. Fuel was supplied by a 29mm square-slide Dell'Orto VHB

carburettor A carburetor (also spelled carburettor) is a device used by an internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the venturi tube in the main meterin ...

Wet sump Within piston engines, a wet sump is part of a lubrication system whereby the crankcase sump is used as an integral oil reservoir. An alternative system is the dry sump, whereby oil is pumped from a shallow sump into an external reservoir.Wet sum ...

lubrication was used and

ignition Ignition may refer to: Science and technology * Firelighting, the human act of creating a fire for warmth, cooking and other uses * Combustion, an exothermic chemical reaction between a fuel and an oxidant * Fusion ignition, the point at which a ...

was by battery and coil until 1973 when Electronic ignition was fitted. Primary drive was by helical gears to a multi-plate wet clutch to a 5 speed

gearbox Propulsion transmission is the mode of transmitting and controlling propulsion power of a machine. The term ''transmission'' properly refers to the whole drivetrain, including clutch, gearbox, prop shaft (for rear-wheel drive vehicles), differe ...

Chain drive Chain drive is a way of transmitting mechanical power from one place to another. It is often used to convey power to the wheels of a vehicle, particularly bicycles and motorcycles. It is also used in a wide variety of machines besides vehicles. ...

took power to the rear wheel, and was wider than the chain used on other models.

Cycle parts

The single cradle frame used the engine as a

stressed member A motorcycle frame is a motorcycle's core structure. It supports the engine, provides a location for the steering and rear suspension, and supports the rider and any passenger or luggage. Also attached to the frame are the fuel tank and battery. A ...

, and had strengthening gussets on the top tube. Rear suspension was by

swinging arm A swingarm, or "swinging arm" (UK), originally known as a swing fork or pivoted fork, is a single or double sided mechanical device which attaches the rear wheel of a motorcycle to its body, allowing it to pivot vertically. The main component of ...

with twin 3-way adjustable Marzocchi

shock absorber A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy (typically heat) which is then dissipated. Most sh ...

s. At the front Marzocchi

telescopic fork A telescopic fork is a form of motorcycle front suspension whose use is so common that it is virtually universal. The telescopic fork uses fork tubes and sliders which contain the springs and dampers. The main advantages of the telescopic fork ...

s were fitted. Brakes were

drums A drum kit (also called a drum set, trap set, or simply drums) is a collection of drums, cymbals, and other Percussion instrument, auxiliary percussion instruments set up to be played by one person. The player (drummer) typically holds a pair o ...

, the front being diameter front and rear. A double-sided front brake was fitted from 1973. Wire wheels with alloy rims were fitted with 350x19 front and 400x18 rear tyres.

References

Bibliography

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External links

* {{Ducati 450 Scrambler Dual-sport motorcycles Motorcycles introduced in 1969 Single-cylinder motorcycles