Ducati 750 Imola Desmo
Encyclopedia
The Ducati 750 Imola Desmo is a race motorcycle
built by Ducati that won the 1972 Imola 200 mile race at the hands of Paul Smart. This win is considered historic by Ducati and its fans in that it helped define Ducati's approach to racing.
(September 10, 1920 – July 18, 2001) made the first sketches for the layout of a new Ducati V twin. By April his drawings were completed, and by July, there was a running motor. By August 1970, there was a complete prototype motorcycle. Taglioni engaged Leopoldo Tartarini, the founder of Italjet, to refine the styling aspects of the new Ducati. (When these two worked together, a memorable Ducati usually emerged.)
In October 1970, the decision was made by Ducati to re enter motorcycle competition. Director Arnaldo Milvio and General Manager Fredmano Spairani, were enthusiastic about racing, and had encouraged Fabio Taglioni to develop the 750 V twin.
, a well known British specialist frame builder of the time. Seeley was asked to develop a racing frame similar to those he had built for G50 Matchless engines. They sent some prototype crankcases for Seeley to work from. Ducati’s new Seely frame was ready in February 1971.
Meanwhile, in less than six months, Fabio Taglioni and his team had designed and built their own complete bike. (The industry norm for concept to production is three years)
and initially produced 61.2 bhp at 11,000 rpm. (Having the same bore and stroke as the later 500 Pantah) All Ducati’s 500 cc GP engines used desmodromic two-valve heads with an 80 degree included valve angle. They used remote float bowl Dell'Orto
40 mm carburettors, and had a six-speed gearbox with a dry, multiplate clutch. Ignition was electronic, provided by nearby Ducati Elettrotecnica, but was initially unreliable. Dual spark plugs were used, and the final ignition system used four coils, two on each side of the frame.
In the beginning Taglioni’s Ducati chassis was used. It had a single Lockheed front disc brake
and a twin leading shoe Fontana rear drum brake
. Dry weight was 135kg (297lb) and it had 18in rims front and rear with 3.00 and 3.25 wheel rims. Wheelbase was 1430mm (56.3in).
In June 1971, Phil Read tested the 500 cc bike with the Seeley frame, and pronounced it the better of the two. The frame was then fitted to Spaggiari's bike as well. It was raced in 1972 by Bruno Spaggiari, Ermanno Guliano and Phil Read.
At least one machine from this initial run is thought to have arrived at the US importer, Berliner
- another early machine (possibly the test mule - complete with Dunstall dual front discs on gaitered Norton forks) was pictured much earlier, on Vic Camp's display at the 1970-71 winter UK national motorcycle show .
In 1971 race results were spoilt by a run of gearbox and ignition problems. Phil Read's second to Agostini in the San Remo Grand Prix, and a fourth, also by Read, at Monza in the Grand Prix delle Nazione were the highlights of the season. .
A Seeley frame 750 cc had been tested by Mike Hailwood at Silverstone in August 1971 with a view to competing in F750. Hailwood decided against it, saying he didn’t think the handling was good enough.
Taglioni had already produced a new frame, for the production bike, incorporating some of the Seeley features. He later said he felt the Seeley frame had been too light for the V twins. They used the production frame for the 1972 Imola bikes.
The 200 Mile formula was first run in Italy in 1972, at Imola. Ducati prepared eight 750 cc bikes for the event. Paul Smart, Bruno Spaggiari, Ermanno Giuliano, and Alan Dunscombe were secured as riders. By now racing fever had set in, and the factory wanted to win. The bikes had the new factory frames and 750 engines, and were once more prepared in a very short time. Wherever possible the bike was lightened, and new 40 mm Dell'Orto carburetors with accelerator pumps were used. These engines delivered 80 hp at 8,500 rpm.
received a lot of publicity from the win.
This inspired the green frame 1974 Ducati 750 Super Sports.
These bikes serve as the inspiration for the retro-styled 2005 Ducati PaulSmart1000LE
, one of the Ducati SportClassic series.
Motorcycle
A motorcycle 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...
built by Ducati that won the 1972 Imola 200 mile race at the hands of Paul Smart. This win is considered historic by Ducati and its fans in that it helped define Ducati's approach to racing.
Design
On March 20th, 1970, Fabio TaglioniFabio Taglioni
Fabio Taglioni was an Italian engineer.Born in Lugo di Romagna, he was chief designer and technical director of Ducati from 1954 until 1989. His desmodromic L-twin design is still used in all current Ducati motorcycle engines...
(September 10, 1920 – July 18, 2001) made the first sketches for the layout of a new Ducati V twin. By April his drawings were completed, and by July, there was a running motor. By August 1970, there was a complete prototype motorcycle. Taglioni engaged Leopoldo Tartarini, the founder of Italjet, to refine the styling aspects of the new Ducati. (When these two worked together, a memorable Ducati usually emerged.)
In October 1970, the decision was made by Ducati to re enter motorcycle competition. Director Arnaldo Milvio and General Manager Fredmano Spairani, were enthusiastic about racing, and had encouraged Fabio Taglioni to develop the 750 V twin.
GP V-twins
In 1971 five 500 cc V twins were built to compete in Italian championship and Grand Prix events. Ducati felt that this would demonstrate the bike before a large audience and gain publicity. If they won, that was a bonus.Seeley
Even before this, in late 1970, and despite Taglioni's opposition to the idea, Spairani wanted the frame for Ducati’s racer to be built by Colin SeeleyColin Seeley
Colin Seeley is a former English motorcycle sidecar racer and, later became a successful motorcycle designer and constructor....
, a well known British specialist frame builder of the time. Seeley was asked to develop a racing frame similar to those he had built for G50 Matchless engines. They sent some prototype crankcases for Seeley to work from. Ducati’s new Seely frame was ready in February 1971.
Meanwhile, in less than six months, Fabio Taglioni and his team had designed and built their own complete bike. (The industry norm for concept to production is three years)
GP Bike technical details
While the 750 and 500 racers were very similar, the 500 had a much shorter 58 mm stroke with its 74 mm bore. It had 10.5:1 compressionCompression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...
and initially produced 61.2 bhp at 11,000 rpm. (Having the same bore and stroke as the later 500 Pantah) All Ducati’s 500 cc GP engines used desmodromic two-valve heads with an 80 degree included valve angle. They used remote float bowl Dell'Orto
Dell'Orto
Dell'Orto is an Italian company, headquartered in Cabiate, specialized in the construction of carburetors and electronic injection systems. The company was founded in 1933 as "Società anonima Gaetano Dell'Orto e figli"...
40 mm carburettors, and had a six-speed gearbox with a dry, multiplate clutch. Ignition was electronic, provided by nearby Ducati Elettrotecnica, but was initially unreliable. Dual spark plugs were used, and the final ignition system used four coils, two on each side of the frame.
In the beginning Taglioni’s Ducati chassis was used. It had a single Lockheed front disc brake
Disc brake
The disc brake or disk brake is a device for slowing or stopping the rotation of a wheel while it is in motion.A brake disc is usually made of cast iron, but may in some cases be made of composites such as reinforced carbon–carbon or ceramic matrix composites. This is connected to the wheel and/or...
and a twin leading shoe Fontana rear drum brake
Drum brake
A drum brake is a brake in which the friction is caused by a set of shoes or pads that press against a rotating drum-shaped part called a brake drum....
. Dry weight was 135kg (297lb) and it had 18in rims front and rear with 3.00 and 3.25 wheel rims. Wheelbase was 1430mm (56.3in).
In June 1971, Phil Read tested the 500 cc bike with the Seeley frame, and pronounced it the better of the two. The frame was then fitted to Spaggiari's bike as well. It was raced in 1972 by Bruno Spaggiari, Ermanno Guliano and Phil Read.
Production 750 GT
Also in June 1971, the first Ducati 750 GT models came out of the factory, distinguished by silver frames, metal-flake paint, fibreglass fuel tanks, 1 1/8" (1.125") Amal carburettors, and twin leading shoe rear brakes.At least one machine from this initial run is thought to have arrived at the US importer, Berliner
Berliner Motor Corporation
Berliner Motor Corporation was the US distributor from the 1950s through the 1980s for several European motorcycle marques, including Ducati, J-Be, Matchless, Moto Guzzi, Norton, Sachs and Zündapp, as well as selling Metzeler tires...
- another early machine (possibly the test mule - complete with Dunstall dual front discs on gaitered Norton forks) was pictured much earlier, on Vic Camp's display at the 1970-71 winter UK national motorcycle show .
The Imola 750 bikes
Taglioni experimented with four valve heads at this time, but failed to produce better power figures than his two valve heads, so the two valve racers continued. He continued to experiment with four valve heads right up to 1973.In 1971 race results were spoilt by a run of gearbox and ignition problems. Phil Read's second to Agostini in the San Remo Grand Prix, and a fourth, also by Read, at Monza in the Grand Prix delle Nazione were the highlights of the season. .
A Seeley frame 750 cc had been tested by Mike Hailwood at Silverstone in August 1971 with a view to competing in F750. Hailwood decided against it, saying he didn’t think the handling was good enough.
Taglioni had already produced a new frame, for the production bike, incorporating some of the Seeley features. He later said he felt the Seeley frame had been too light for the V twins. They used the production frame for the 1972 Imola bikes.
The 200 Mile formula was first run in Italy in 1972, at Imola. Ducati prepared eight 750 cc bikes for the event. Paul Smart, Bruno Spaggiari, Ermanno Giuliano, and Alan Dunscombe were secured as riders. By now racing fever had set in, and the factory wanted to win. The bikes had the new factory frames and 750 engines, and were once more prepared in a very short time. Wherever possible the bike was lightened, and new 40 mm Dell'Orto carburetors with accelerator pumps were used. These engines delivered 80 hp at 8,500 rpm.
Victory
In that Imola 200 held in April, Smart and Spaggiari came in first and second. Ducati V-twin motorcyclesDucati V-twin motorcycles
The next new Ducati engine to appear after the Ducati Apollo was the 90°V twin, initial Grand Prix racing versions being 500 cc, and the production bikes were 750 cc. There was also the Ducati 750 Imola Desmo that won at Imola in 1972. These engines had bevel gear shaft drive to the overhead...
received a lot of publicity from the win.
This inspired the green frame 1974 Ducati 750 Super Sports.
These bikes serve as the inspiration for the retro-styled 2005 Ducati PaulSmart1000LE
Ducati PaulSmart1000LE
The Ducati PaulSmart1000LE is a retro styled "naked" sportbike built by Ducati to commemorate Paul Smart's win at the Imola 200 km race in 1972, a win that helped define Ducati's future approach to racing...
, one of the Ducati SportClassic series.
External links
- 750 Imola Desmo at Ducati's official website.