1957 Ducati GP 125

Lot details
Registration No: N/A
Frame No: DM542
Engine No: 542
cc: 125
MOT Expiry Date: N/A

Ducati had risen from the ashes left by the Second World War with the help of both the Italian Government and the Vatican and by 1948 were once again producing radios, cameras, cinema projectors and, in a new field for the company, motorcycles, in the form of the Cucciolo 48cc "clip-on" engine. The success of the unit prompted the creation of a complete motorcycle, initially in partnership with Aero Caproni which continued until 1950. The success of the Cucciolo underpinned work on a new range of single cylinder machines in the 65cc class using push rod valve operation which quickly grew to encompass 100cc models. The 1953 Milan Show witnessed the introduction of the first sporting Ducati, the 98S, which was powered by a tuned version of the ohv single. Although successful commercially, the little machine was outclassed by its rivals when used in long distance races such as the Giro d'Italia and the Milano - Taranto. Success in these events guaranteed increased sales in the increasingly competitive Italian market and prompted Ducati Meccanica to hire Fabio Taglioni to design a new engine capable of competing with and beating rival machines from the likes of Laverda. Taglioni had graduated from Bologna University before joining the successful FB Mondial team. On joining Ducati Taglioni undertook the design of what was to become the 98cc Gran Sport or Marianna, a machine that would dominate its class in long distance racing and lay the foundation for the development of the hugely successful over head cam and "desmo" singles that would emerge from Bologna during the next decade and a half.
The new model was designed as a racing machine first and foremost, with the capacity for further development being engineered into its design from the outset. Displacing 99.66cc, it featured a bevel gear driven over head camshaft engine that produced 9 bhp at 9,000rpm. First seen in 1955, it won its class convincingly in that years Giro d'Italia and Milano - Taranto races establishing a dominance that would continue until the class was scrapped in 1958. A 125cc version quickly followed achieving similar levels of success in its class. With success in the road events now assured Ducati turned their attention to the world stage with the development of their first pure racing motorcycle, the 125 GP.
Introduced in 1956 the Bialbero exploited the development potential of the Gran Sport engine to the full. In its first form the bottom end of the engine was essentially the same as that employed by the Gran Sport, the significant difference being the cylinder head which employed two gear driven camshafts hidden behind a distinctive cover. The new model produced a claimed 16bhp at 11,500 rpm but suffered from reliability issues at sustained high revs. Taglioni responded to these problems by replacing the valve springs with a positive "desmodromic" valve gear on a batch of works machines built during 1956. 1957 became a season of development for the works bikes, but also afforded the factory the opportunity to develop a batch of refined Bialbero's for privateers. The new model adopted a new full frame with two lower rails closing off the previously open front frame. Approximately fifty examples are believed t have been built between 1957 and 1959 the new machine quickly established itself as the most competitive 125 class motorcycle available to privateers.
This example of the 125 Grand Prix was purchased by the present owner in 1980 from a Swiss collector. It is believed to have been ridden in period by Tartarini Leopoldo. The machine, which is pictured in Mick Walkers book "The Ducati Racing Story" on page 44, is offered in totally original condition and is described as being ready to use. The engine has been rebored from its original 55.25 to 58mm which combines with a 52mm stroke to give a displacement of 138cc. An original dustbin fairing and complimentary seat unit are included with the machine and it is interesting to note that the seat unit fitted to the motorcycle is made of copper, a peculiarity of the model.