Ducati Monza Explained

Ducati Monza
Manufacturer:Ducati
Production:1961-1968
Class:Standard
Engine:Air-cooled bevel drive SOHC single cylinder four stroke
Bore Stroke:74mm57.8mm
Compression:8:1
Top Speed:128kph
Power:22bhp @7200 rpm
Transmission:Multiplate wet clutch, 4 speed (1961-64) 5 speed (1965-68)
Frame:Single cradle
Suspension:Front: telescopic forks
Rear: swinging arm
Brakes:Drum front & rear
Tires:Front: 275x18
Rear: 300x18
Wheelbase:1320mm
Length:2000mm
Width:800mm
Seat Height:800mm
Dry Weight:125kg (276lb)
Sp:uk

The Ducati Monza is a 249cc single cylinder bevel drive SOHC motorcycle produced by the Italian manufacturer Ducati from 1961 to 1968. It was the touring version of Ducati's first 250 cc road bike. Reviews of the Monza praised its speed, road holding, engine smoothness and brakes.

History

Following the success in racing of the 250 F3, and using an engine based on that of the racer, Ducati introduced its first 250 cc road bikes at the April 1961 Milan Fair. The bikes were offered in two versions, the touring Monza and sports Diana. The Monza has a softer cam, a more padded seat, deeper mudguards, higher handlebars and a smaller tank.

The 1963 US model was finished in black and chrome.

In 1964 the electrics were updated and the kick start ratio was changed. The gearbox was changed to a 5 speed unit in 1965, along with a smaller 13L tank.

The styling was updated in 1966 with a new tank, more padded seat, side panels and front and rear lights. The styling was shared with the Monza Junior and the Sebring.

A square headlight was fitted in 1967 and 68.

The American motorcycle market slumped and in 1967 Ducati importers, Berliner Motor Corporation were in financial trouble and refused a consignment of 3,500 machines from the factory. These machines were sold to Liverpool businessman Bill Hannah, who sold the bikes to the public between 1968 and 1972. Some of these were Monzas which were sold at a discounted price. Hannah offered no support or spares network for the bikes he sold which damaged Ducati's reputation in the UK.

The bike was fitted with the improved 'wide case' engine in 1968, the final year of productions. Two versions were made of the Monza, one for the US and the other for Europe.

Technical details

Engine and transmission

The single cylinder bevel drive OHC engine was of unit construction and had alloy head and alloy barrels with cast iron liners. Ball bearings were used in the main bearings and big end and hairspring valve springs were used to close the valves. Bore and stroke were 74mm57.8mm giving a displacement of 248cc. Compression ratio was 8:1. Claimed power output was 22bhp @7,200 rpm, giving the machine a top speed of 128kph.

Fuel was delivered by a 24 mm Dell'Orto UFB carburettor. Wet sump lubrication was used and ignition was by battery and coil with the points under a cover on the right hand side of the engine.

Primary drive was by helical gears to a multi-plate wet clutch and 4 speed gearbox. A 5 speed cluster was fitted from 1965. Chain drive took power to the rear wheel.

The 'wide case' engine was introduced in 1968, the last year of production. Although the specifications were similar to the 'narrow case' engine, the new engine had a stronger bottom end with bigger main bearings and big end. Capacity of the wet sump was increased from 4 to 5.5 pints and the kickstart mechanism has been upgraded from the earlier models.

Cycle parts

The single cradle frame used the engine as a stressed member. When the wide case engine was introduced the frame was modified for the wider rear mountings and twin rear loops were added which made the frame stronger and stiffer. Rear suspension was by swinging arm with twin 3-way adjustable Marzocchi shock absorbers. At the front Marzocchi telescopic forks were fitted. Brakes were drums, the front being 180mm diameter and the rear 160mm.

References

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