HOME/Ducati Racing in the Seventies
12 May 2011 by Hans Smid
In the early seventies Fabio Taglioni was at the end of technical possibilities with the single cylinder 450 Desmo’s. The successful engine could not be enlarged anymore without losing the properties it was so beloved for.
Ducati Meccanica was in desperate need for something completely new in the race for bigger, faster and more, which had just begun after Honda's daring project with the successful CB 750. One was not taken seriously anymore with a bike under 650cc...
Taglioni developed a technical masterpiece known as the 1200cc Apollo Four developed for the American Police force. Regretfully it didn't come any further than the stadium of prototype, partly due to its complexity. Under pressure of Ducati managers Fredmano Spairani and Arnoldo Milvio orders were given to Taglioni to design a new draught a revolutionary engine concept that would lead Ducati into the heavier class. The result was both simple and brilliant.
Fabio combined two bevel drive single cylinders on a common crank-shaft that led to the first, nowadays so characteristic, Ducati trademark, the L-twin. When in spring 1970 the drawing-tables were cleared for other designs and ideas, the first prototype was tested in July. And with success, because only sixty days later the first Ducati 750 GT struck the Italian press like thunder. Though sporty looking, the driving characteristics were more those of a touring model.
Because of the L-twin concept, this Ducati was "built around", it became a model with a rather long wheelbase (1550 mm). The engine was equipped with 28 bearings, no less than 9 of those just to lead the bevel gears, so the idea might have been simple, the construction wasn't. The 750 GT by the way was the first Ducati with 12 Volt electric circuit. The model was surprisingly light with 185 kg. The road holding was quit excellent and proved a good starting-point for developing a more sporting machine.
The first attempt to make the engine more powerful was made by higher compression and mounting bigger (32 mm) Dell'Orto's. It was called the Ducati 750 Sport in 1972 and it had black crankcases. This model was very Spartan and didn't attract many potential buyers. (A pity, even nowadays; they are beautiful and very hard to find in original condition) Times were very hard for the Ducati factory; the price of a 750 S was considered too high. But it would be that same year 1972 that would give the dark cloud a silver lining for the struggling factory in Bologna.
Preparing for Imola
Ducati Meccanica Bologna had tried to draw the attention of some riders such as Jarno Saarinen, Renzo Pasolini and later Barry Sheene for riding the new 750 SS in the 200 miles race on the Imola circuit. None of them looked at the newcomer with its long wheelbase as a potential winner and refused the opportunity. Seven racers were being prepared. The 39 year old factory test rider Bruno Spaggiari was first choice because of his experience at the Imola track and the fact that he was a loyal and devoted employee, who had been riding on almost everything Taglioni had invented from the fifties until that moment. Ermano Giuliano and George Dunscombe both got a machine as well. Faith determined that British rider Paul Smart would not be starting on a Triumph triple as planned.
In the absence of Paul, his wife Maggie had promised Vic Camp with good intentions that "her" Paul would give it a try on the brand new Ducati 750 SS. Once returned Smart wasn't very happy with his wife's idea at first, but changed his mind after a good conversation with Camp, the British Ducati importer. This way he could collect the starting fee and he would still be able to ride Imola!
Smart and Spaggiari had two machines at their disposal; one racer was kept for spare. When the mighty Dell'Orto's started breathing and the huge amount of oil had the right temperature, Smart surprised everyone including himself during the training by matching the record of the fastest lap held by Agostini. The enthusiasm of team-mate Spaggiari started to infect Smart from that moment on. It was unbelievable! This was the very first time these new machines had actually been riding! Even more astonishing was the fact, that all desmo engines had been started (brought to life) for the first time by factory test rider Franco Farne only a week ago. Just three days were left now 'till the moment of truth: Imola, racing heart of Italy. No more time for real modifications; maybe some small changes could be made for the individual riders, no more. All they could hope for was a miracle… They didn't realise, they were already sitting right on top of it!
It was the intuitive vision of Fabio Taglioni, the small sorcerer, that without mistakes, roundabouts or costly research had resulted in a magical racing machine. A shortage of about 10 horsepower was compensated adequately by fantastic road holding, curving, handling and breaking. When a black cloud darkened the Modena sun and rain poured down after a successful training, Paul Smart said to Vic Camp prophetically: "You know; this might all work out very well.”
It is April 23rd 1972. About 70.000 spectators are looking down from the stands to the factory racing teams of MV Agusta, Triumph, Norton, Guzzi, BSA, Honda and to the factory-supported teams of BMW, Suzuki, Kawasaki and Laverda. The occasional Ducati team had to fight an uneven battle against the world’s best riders like Jefferies, Read, Villa, Grant, Cooper, Tait, Gallina, Emde, Pickrell and Agostini.
Where other riders had immense financial and material support, the Ducati racing team had to make do with very little training experience, on almost untuned and unmodified standard racers with frames that were picked straight from the production-line. Even the centre stand mountings were still visible. All eyes were fixed on the riders, concentrated and ready to go…
As expected Giacomo Agostini took lead. But after four laps the Ducati fans got outrageous the moment Paul Smarts number 16 overtook the favorite. Disillusion among the competition became even bigger when teammate Spaggiari with number 9 showed the backside of the high swept Conti's to Agostini and his fellow-rivals. The Ducati crew went mad. The final battle, much unexpected, was between Bruno Spaggiari and Paul Smart, who fought for five rounds in what was to become a murder between two brothers.
Actually it was Spaggiari, who was in lead in the final round! Unfortunately he suffered from air bubbles in his fuel system. The restrained engine and a too widely taken curve gave Paul the opportunity to overtake Bruno's desmo in one of the last curves on the circuit. It would bring him eternal fame and immortality. Some think it is a pity Spaggiari didn't see the black & white finish flag first; he would have deserved it with his impressing career as a Ducati test rider.
The double Imola victory in 1972 was beyond anyone's imagination and very important to Ducati. One might even doubt if the name Ducati would still have been on the tank of present Italian stallions without this legendary win. Truth is that after Daytona the 750 SS was designed perfectly for the Imola circuit by Taglioni. Related to the powerful Japanese four cylinders the 10hp lower engine performance was of minor importance thanks to the fantastic handling of the machine. This doesn't make this victory less heroic; racing is not just a matter of supreme horsepower, it's the perfect balance between man and machine in the most literal way.
As always Fabio Taglioni had made a perfect study of the circumstances, without mathematical calculations, long term research or high prototype costs. The little man was great in his intuitive way of acting that proved to be close to perfection afterwards. While Smart and Spaggiari were fighting marvellous riders, Taglioni stood all alone against huge research teams, divided in sub teams, who could afford the luxury of studying one specific problem or detail. Especially the Japanese had a mathematical way of dealing with problems; they tried ten different things, kept the best result and threw the nine remaining on the junkyard.
The poor Ducati factory couldn't afford this kind of research. Smart and Spaggiari wrote history by winning Imola, but Fabio Taglioni was the modest inventor, who had managed to create the impossible. The name Ducati was taken seriously from now on in the higher class after their sweet little singles. And it wouldn't be the last time, they would be heard from in the superbike-top. Names like Hailwood and Fogarty would have their influence on sales numbers. But that's another story...
The success on the Imola track inspired the Ducati management to the production of a real "street-legal" 750 desmo replica. This 750 Super Sport with its round crankcases was produced in small amounts only; the term -mass production- was an unknown luxury to the Ducati employees in the early seventies. This 750 is a very rare and valuable collector’s item nowadays. It was a striking racer with beautiful details, like the transparent "looking-glass" in the fibreglass tank.
The azurro metallizato (metallic blue) frame that was fitted around the characteristic and impressive engine was in perfect harmony with the silver-grey top half, tank, saddle body and covers. "Beyond engineering, into art", Dave Minton wrote in March 1976 in Motor Cyclist Illustrated. A machine built for men; there was no room for your girlfriend on the seat anyway! The Ducati 750 Super Sport was the first street bike with three disc brakes.
It was only a matter of time before the 900 SS would appear. Kawasaki had already proven, that 750 was not the limit with the bigger Z1 Super Four, that struck back Honda for the nasty surprise in '68. The 750 SS remained in production, this time with the new square crankcase. The smaller engine had almost the same capacities as the 900 SS. This 750 square case is as rare as the round case; not many more were produced. Who wanted a 750, when 900 was available? The big desmo could easily be used as a standard production racer with low weight, strong frame, Marzocchi suspension and good manners. Just remove the centre stand, that's all! You won't get betrayed by the looks; this really is a racing champion!
More Racing Success; up to 900 cc
In 1973 Spaggiari once more was successful on Imola with his 750 Ducati. This time he finished second before the eyes of 100.000 spectators. Bruno Kneubuhler and Mick Grant had to stop on their Ducati's with mechanical problems; a NCR Ducati with Claudio Loigo ended up fifteenth place.
A bigger engine had to be constructed in order to remain serious competitor between the mighty four cylinders from Honda and Kawasaki. Two 86mm pistons from the 450cc desmo were mounted in a sand casted 750 crankcase. Stroke became 74,4 mm. The now created 864cc engine was in fact an enlarged 750 with a bigger bore. It was capable of producing 86 hp at 8.200 rpm. The first race, this engine was operational, was Barcelona July '73. Salvador Canellas and Bejamin Grau won together after 720 laps with an average speed of 114,3 km per hour. They had been 16 laps ahead of the number two.
In 1975 this team won again, this time on a 905 cc desmo L-twin with a narrower crankcase. This way the ground clearance was improved considerably. They even accomplished 11 more laps than in '73. The glory of the 900 SS became legendary after the comeback of Mike "the bike" Hailwood in 1978 during the TT on the Isle of Man. But that's another story, I'm afraid. The famous 900SS would finish victorious many more times in the late seventies used as production racer.
Hans Smid is a classic motorcycle enthusiast, journalist and collector. He owns the Classic Seventies Superbike Collection and publishes articles in Het Motorrijwiel and in his online newsletter. Follow him on his blog at http://www.hanssmid.nl