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Motorcycle Investor mag

Imola Ducatis

(by Ian Falloon, Mar 2022)

The machines that really put Ducati on the performance map

April 23, 1972, was the day when a brace of specially prepared desmodromic 750 racers took on the best the world’s manufacturers had to offer, and trounced them convincingly. It was the inaugural Imola 200, the “Daytona of Europe”, for Formula 750 machines, racing 750cc machines with production-based motors.

The win at Imola marked the transition for Ducati, from a relatively small and unknown Italian manufacturer, primarily of small capacity single cylinder bikes, to that of a marque equal to any other. Within Italy, and to certain cognoscenti in other countries, Taglioni and Ducati were respected for technical excellence and innovation. Yet, in production terms, Ducati was a minor manufacturer of motorcycles. Imola changed that.

The impetus for developing a racing 750 had occurred back in July 1971. In a one-off ride, Mike Hailwood was to pilot a prototype Formula 750 machine at Silverstone in August 1971. However, although Hailwood tested the bike, and recorded a sixth fastest practice lap for the F750 race, he elected not to race it. Hailwood told Motor Cycle magazine, “It did not handle well enough. This isn’t surprising because it is only three weeks old and has never been raced before; it just needs a bit of sorting out. It should be good then”.

With the support of Fredmano Spairani, Fabio Taglioni was given the brief to make an all-out assault on this important race. It was being heavily promoted, and nine different factories had entered works supported teams. In order to assess the level of competition,

Taglioni made the trip to Daytona in March 1972, and came away impressed by the well-developed Japanese racers. He realised that he couldn’t tackle them head on, he didn’t have the resources. Utilising proven technology from the 350 Desmo and 500 racers, he aimed to build a balanced machine, with handling and braking matched to useable horsepower.

Upon his return from Daytona, serious work began on developing the Imola bikes. Surprisingly, Taglioni started with standard 750GT street bikes. They had 750 engine numbers, indicating that bikes were just taken off the production line and into the racing department. The frames still had centre-stand mounts and stock frames.

They also had machined production leading axle Marzocchi forks, but there was more to these bikes than met the eye. The engines used desmodromic valve control enabling the engine to run to 9200rpm. These were the first bikes to use the “Imola” desmodromic camshafts. Power of 84bhp at 8800 rpm was claimed at the rear wheel, but more importantly it was the spread of power that was so advantageous.

At 7000 rpm the engine was said to make 70bhp. Compression was up to 10:1 and these engines still used the wide, 80 degree included valve angle. They also used the first versions of the new 40mm Dell’Orto PHM concentric carburettor.

In order to keep combustion temperatures down, an oil cooling system was fitted that treated the oil to the cylinder heads, and dual-plug ignition installed with an additional 10mm Lodge spark plug. This enabled ignition advance to be cut back to 34 degrees before top dead centre.

With the alternator removed from the right side of the crankshaft, total loss battery and coil ignition, still by dual points, was employed. Since his experience with electronic ignition on the 500, Fabio Taglioni was wary of employing it on the 750 for Imola, and was also worried about heat build-up inside the fairing over such a long race. Thus the condensers were mounted on the front frame down-tubes, away from the heat of the engine.

Further weight was saved by completely removing the kickstart mechanism, also increasing ground clearance on the right side. Braking was uprated to two Lockheed front discs, and a rear 230mm disc replacing the road bike’s drum. With only left side calipers in stock from the street bikes, these were used all round, the right side front having an unusually long brake hose.

A high rise exhaust pipe was on the left, but not on the right. Imola had predominantly left hand corners, but ground clearance was still a problem because racing tyres required an 18 inch front wheel instead of a 19 inch. Total dry weight of these racers was 392lb (178kg), and they were reputed to pull the tallest available gearing, giving 169mph (272km/h).

Ducati approached Jarno Saarinen, Renzo Pasolini, and then in February, Barry Sheene. All had declined, not feeling that the Ducati would be competitive. Ducati already had the evergreen 39-year-old Bruno Spaggiari who had raced every factory bike since the 1950s, and who knew the Imola circuit intimately.

To partner Spaggiari would be the younger Ermanno Giuliano who had raced the 500 Ducati throughout 1971, and to fill the third berth, English rider Alan Dunscombe. The latter had already been racing a modified 750GT for English importer Vic Camp.

Spairani now only required a top line F750 racer to ride the last bike and, through Vic Camp, managed to secure Paul Smart at the last minute. Originally planning to ride a Triumph Triple, the deal fell through, and reluctantly Smart flew to Italy.

While a 750 Desmo with Sport bodywork had been tested at Modena in March, with further tests by Spaggiari with revised bodywork on April 6, it wasn’t until the April 19 that the Imola racers were started up for the first time at Modena. Too late to correct any defects, Taglioni was quietly confident.

Smart had equalled Agostini’s lap record, set on a 500cc MV Agusta Grand Prix bike. In their specially constructed glass-sided transporter, all seven Ducatis were transported the 40km (25 miles) to Imola. Two each for Smart and Spaggiari, one for Discombe and Giuliano, and one spare.

On race day, 70,000 spectators crammed into Autodromo Dino Ferrari at Imola. With works machines in abundance from MV Agusta, Honda, Norton, Moto Guzzi, Triumph and BSA, alongside works supported Kawasaki, Laverda, Suzuki and BMW, they had hopefully come to see the Italian factories beat the Japanese teams that had dominated Daytona.

The best riders in the world were there too. Giacomo Agostini, Phil Read, Roberto Gallina, Walter Villa, Ray Pickrell, Tony Jeffries, John Cooper, Percy Tait, Ron Grant and Daytona winner, Don Emde.

In practice, Spaggiari, followed by Smart, had set the fastest time. Imola with its fast sweeping curves, some smooth, others bumpy, and its up and down topography seemed to suit the Ducatis. Unlike Daytona this was no mere horsepower circuit. This was Imola before the advent of chicanes, a fast European circuit in the traditional style.

Agostini, on a specially prepared 750 MV led the start. This MV, while still with the shaft-drive of the road bikes, had a Grand Prix style frame with 500GP forks and brakes. At the end of the fourth lap Smart overtook Agostini, followed a lap later Spaggiari. From then-on the two Ducatis were untroubled out in front and in the final five laps they were both racing for the lead.

Spaggiari nipped in front, but on the final lap his bike started to misfire as he was low on fuel. He ran wide on a sweeper, allowing Smart to take a comfortable victory. It had been a great day for Ducati.

It wasn’t so bad for Paul Smart either, as he took home 7,080,000 Lire in prize money. Spairani was so excited that he donated the winning bike to Smart.

The race speed over 200 miles had been an astonishing 97.76mph (157.35km/h), with the fastest lap of 100.1mph (161.11km/h) being shared equally by Smart, Spaggiari, and Agostini. It was the start of the modern Ducati legend.