Sunday, February 5, 2012

MONDIAL 1957 125CC DOHC


The Fratelli Boselli Mondial motorcycle company exploded onto the motorcycle racing scene in 1948, where practically straight off the drawing board their brand new double-overhead camshaft 125cc machine set speed records in the standing start ¼ mile and kilometer sprints.  While the motorcycle division of F.B. Mondial was new, the Boselli family had roots in the Italian motorcycle industry which reached back to the 1920s, when Guiseppe Boselli was a partner and in the G.D. marque, and raced their machines.  His friend Oreste Drusiani manufactured the engines for the G.D. and later the C.M. motorcycles of Bologna; Guiseppe was on the Board of both companies. 
In 1929, Guiseppe convinced his brothers (‘fratelli’) to start a company (F.B.) making commercial three-wheelers, within Drusiani’s industrial space.  These vehicles were successful pre-war, but the factory was destroyed in the mid-1940s. By 1946, the factory was back in production of commercial vehicles. 










Alfredo Drusiani, son of Oreste, designed and built a very advanced Double Over Head Camshaft (dohc) motor in 1948, which must have set Guiseppe’s dormant racing ambitions alight, for he immediately purchased this prototype engine and set about creating a motorcycle in collaboration with young Alfredo.  While certainly not the first dohc engine, such a technically advanced specification was unheard of in the ultra-lightweight 125cc capacity, which was dominated at that time by two-stroke single-cylinder machines of very simple design.

Drusiani’s engine used a short vertical shaft beside the cylinder to drive a train of 5 gears above the cylinder head, the outermost of which incorporated the camshafts.  The crankcases had no ‘splits’, being a unitary casting with access ports to assemble and repair the crankshaft, gearbox, clutch, etc.   The stroke of the motor was nearly ‘square’ at 53x56.4mm, which meant, in conjunction with the extremely precise valve actuation provided by cams directly above the valves, the engine would rev freely and provide excellent power.

The first race of the new F.B. Mondial, in September 1948 at the GP of Nations (Faenza), ended prematurely when their petrol tank split.  There had been so little time to refine the new machine, that a Moto Guzzi  tank had been used on this test mule.  Shortly afterwards, in October, using crude aluminum fairings, World Records were set in the standing start ¼ mile and one kilometer 125cc class.  Later that month Mondial tasted success on the GP circuit, with a win at Monza.

Development of this remarkable little motorcycle coincided with the introduction of the Grand Prix World Championship racing series in 1949.  With quite a jump on the competition, Mondial won every single race in the 125cc series in 1949, 50, and 51, while rivals MV Agusta and Benelli developed similar machinery to contest this runaway success.  MV Agusta finally pipped Mondial in the 1952 World Championship by four points.

Alfredo Drusiani left the company in 1953 to found Moto Comet, and during his absence Mondial did not seriously contest the GP circuit, concentrating successfully on the Italian championship and long distance road races such as the Giro d’Italia and Milano-Taranto.

After the failure of the Moto Comet venture, in 1956 Drusiani returned as race chief of Mondial, and redesigned his 125cc engine, while adding a 250cc dohc GP machine to the roster, both of which were housed in updated chassis.  ‘Dustbin’ fairings, which totally enclosed the front wheel, were incorporated for the first time on these machines, following their use by competitors in the preceding years.   The tail section was also enclosed, leaving only room for the rider’s legs within a wind-cheating ‘egg’ which boosted the top speed of the motorcycle by as much as 20mph.

While racing results for ’56 were mixed, Drusiani was busy creating wholly new 125cc and 250cc engines, using a cascade of gears to drive their double overhead camshafts rather than the old shaft-and-bevel arrangement.  Echoing their 1949 season, Mondial won both the 125cc and 250cc World Championships with this new design.  The enclosed aerodynamic bodywork was refined further to the elegant state seen on the motorcycle for sale.

The 1957 Mondial GP racer as seen here proved to be the ultimate development of their racing efforts on the International level, for at the end of the season, Mondial, in concert with Gilera and Moto Guzzi, withdrew from GP competition, citing the ever-rising expense of development coupled with a weakening market for their products.  Shades of 2010!

This 1957 125cc Mondial dohc GP racer was sold by the Mondial factory in the late 1970s to Piero Nerini of Prato, Italy, as part of a clear-out of the race department’s remaining spares and motorcycles.  Nerini retained these motorcycles for nearly 25 years, before selling his collection.  John Goldman purchased this machine and three other racing Mondials from Nerini at that time.   While the 1957 racer was complete and in good condition, many parts weren’t correct for the year, and the important bodywork was missing – a typical scenario, as factory machines were loaned out to racers after 1957 for various competitions, and full-enclosure fairings were banned at that time due to safety concerns.  Thus, original ‘dustbins’ are extremely rare.

Goldman, ever the stickler for authenticity, sought the help of Giancarlo Morbidelli (whose own motorcycles won the 125cc and 250cc GP World Championships in 1975-77) to assist with bringing the Mondial back to a fully correct and accurate state for the 1957 race season.  Morbidelli currently owns a private motorcycle museum in Pesaro, Italy, which features hundreds of important motorcycles, and is renowned as a restorer with a passion for accuracy and authenticity in the motorcycles he displays.

Moved by the importance and rarity of Goldman’s 1957 Mondial 125cc GP, Morbidelli agreed to restore the motorcycle in the workshop adjacent to his museum, to its exact 1957 racing specification.  One significant hurdle, the missing bodywork, was overcome when the artisan who originally fabricated the Mondial fairings in 1957 was contracted to create a copy of his own handiwork from 50 years prior, using the only known surviving set of Mondial 125cc bodywork as a pattern.
It took Morbidelli several years to locate original parts for this project, and with the completion of the bodywork and mechanical restoration, the Mondial was handed to restorer Roberto Totti of Bologna for the final painting, chrome, and assembly.  Totti is considered one of the top restoration specialists in Italy, and he completed this Mondial in 2009.

The Mondial racing team in 1957 for the 125cc class included Tarquinio Provini, Cecil Sandford, and Sammy Miller.  This machine was raced either by Miller or Sandford, as Provini (who won the 125cc Championship that year) preferred the 1956 engine design.  It is not known whether Miller and Sandford rode one machine exclusively for Mondial during the year, but each man did well in the Championship that year, with Miller gaining 4th place, Sandford 6th. Thus, this Mondial has an excellent pedigree as a factory race machine, and is considered the most correct and accurate restoration in existence of the ultimate Mondial racer.

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