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Motorcycle Investor mag

Ducati's landmark Imola victory

(by Ian Falloon, April 23, 2022)

Today marks the 50th anniversary of what many regard as the true start of the Ducati legend

In Ducati folklore the 1972 Imola 200-mile race is a defining event. Before Imola Ducati was a minor Italian motorcycle manufacturer of esoteric four-stroke singles with strange valve gear, but after Imola they could take on the worlds best and comprehensively beat them. As Ducati’s great engineer Fabio Taglioni said in 1974, “When we won at Imola we won the market too.” It was the Imola victory that ostensibly set the stage for Ducati’s subsequent success.

Imola would never have happened if Ducati hadn’t just introduced their 750cc V-Twin, and this only came about through the 1969 company restructure. The decade of the 1960s had been difficult for Ducati. A series of dubious business ventures nearly strangled the company, and it would have sunk into oblivion like many Italian motorcycle manufacturers but for quasi government bailout every year.

During 1969 the financial situation was so precarious that Ducati was absorbed as part of the EFIM (Ente Finanzaria per gli Industrie Metalmeccaniche) group. At the end of 1969 new directors were appointed and Ducati Meccanica was given a new lease of life. Arnaldo Milvio was appointed Managing Director, with Fredmano Spairani as Coordinating Director, and they came to Ducati Meccanica with a fresh approach. Somehow, they found the resources to develop the new 750 Twin and instigate a racing program.

When the 750 was conceived Fabio Taglioni was 49 years old. But the father of desmodromic valve gear for motorcycles was virtually unknown outside Italy, and Ducati was still a minor motorcycle manufacturer in world terms. Despite the new management, economic viability was essential, and Taglioni was instructed to utilize as much carryover technology from the existing range of singles as possible.

A V-twin made sense as many features of the existing overhead camshaft singles could be incorporated, and Taglioni liked the idea of an engine that was little wider than a single. Taglioni chose a 90-degree V-twin layout, a carryover from the V-four Apollo seven years earlier. In one of several interviews I asked Taglioni why he chose the 90-degree cylinder layout. Taglioni replied, “The 90-degree L-twin provided perfect primary balance. The engine can be very smooth, with only some high frequency secondary imbalance, and with a narrow crankshaft there is virtually no rocking couple. Also the twin can be narrow so the engine can be kept low in the frame while maintaining good ground clearance.”

Along with the development of the 750 Taglioni was also working on a 500cc Grand Prix twin. With a special frame by Colin Seeley Bruno Spaggiari, and later Phil Read, campaigned this in mainly Italian events during 1970 and 1971. Although the twin struggled against the MV triples much was learnt that would help when it came to the preparation of the Imola machines in 1972. A 750cc version was also built, Mike Hailwood testing this at Silverstone in July 1971.He qualified sixth fastest but decided not to ride it as he felt it didn’t handle well enough.

With the announcement of the Imola 200 “Daytona of Europe” to be held on April 23, 1972, Spairani instructed Taglioni to mount a full-scale attempt at winning the race. With record prize money the Imola 200 was to be one of the biggest race meetings ever staged in Europe, and Imola was in Ducati’s back yard, only a short skid down the autostrada from Bologna. Spairani was determined to hire a top rider to head a line-up of six entries. He approached Jarno Saarinen, Renzo Pasolini, and Barry Sheene, Spairani visiting Sheene at the end of February to secure the deal. Although Sheene didn’t end up riding the Ducati because they couldn’t agree to the fee, he was still listed in the program riding number 18.

In early March Taglioni and a group of leading Italian motorcycle engineers traveled to Daytona for the 200-mile Formula 750 race. Taglioni came back optimistic. While he found the speed of the 350 Yamahas devastating he knew they weren’t eligible to race at Imola. With the Yamaha out of the equation Taglioni looked at the rest of the competition. Mostly four-stroke, he reasoned he could build a better-balanced machine particularly suited to the Imola circuit. He took ten production 750 frames and began building a batch of Formula 750 racers. It was originally intended to build ten machines for six riders, but according to Taglioni in an interview in 1995 only six were officially certified, with one spare, for four riders.

Right until the last minute there was uncertainty as to who would ride the works Ducatis. Ducati hadn’t mounted such a factory racing effort since 1958 and all the top riders were skeptical, none believing the Ducati twin would be competitive. Already signed were Bruno Spaggiari (on number 9), Ermanno Giuliano (45), Vic Camp’s rider Alan Dunscombe (39), and Gilberto Parlotti (24), although he also didn’t race.

Needing another top rider, British distributor Vic Camp suggested Spairani approach Paul Smart, then racing a Kawasaki H2-R for Team Hansen in America. As there was no race in America that weekend Paul’s wife Maggie accepted the invitation in his absence and Smart initially wasn’t too impressed. But Ducati was paying good money and after a Triumph ride fell through, Smart was soon down in the program on Ducati number 16, listed just ahead of his brother-in-law Barry Sheene.

The first Imola race bike was completed in time for a Modena test by Spaggiari on 6 April in preparation for the first official test session on 19 April. Incredibly this was only four days before the race and only five machines were available, Smart, Dunscombe, and Giuliano riding them for the first time. Smart had only just arrived from a race at Road Atlanta and was initially unimpressed saying, “It was so long it looked will it would never go around a corner, but after riding it I found it deceptively fast. Ducati had obviously put a lot of effort into it. It just felt slow revving, like it fired every lamp post.”

All Smart found to criticize were the street Dunlop K81 “TT100” tires, and extremely high footpegs. After altering the footpegs Smart went out again, breaking Agostini’s lap record on street tires. Ducati was reluctant to change the tires, fearing racing tires wouldn’t last 200 miles but Smart persuaded Taglioni to procure some Dunlop KR83 and KR84 racing tires.

Although the racing desmodromic 750s looked surprisingly similar to the GT and Sport, they were highly developed factory racers sharing little with the production 750. Phil Schilling, Cycle magazine's managing editor at the time, saw the bikes in the Ducati race shop a few days before Imola. He wrote, "The first thing I saw, the thing that immediately dented my mind, was a center stand.

These factory racers were all parked on center stands, stock center stands, which were connected to stock frames, which joined standard front forks and near-stock swingarms. And the production-line frames held embarrassingly standard-looking engines. Sure, there were special pieces: big Dell'Orto carburetors, high-rise/low-rise megaphones, dual discs in the front and single discs in the rear, oil coolers, hydraulic steering dampers, and racing shocks. But where were all the really trick parts? There weren't any."

Schilling’s observations were as accurate as could be made at the time, but as with all factory racing Ducatis there was more to the Imola racers than met the eye. The frames may have started as production Verlicchi items (with center and side stand mounts and frame numbers) but were considerably modified to accept the large fiberglass fuel tank and provide a suitable racing riding position. The fiberglass fuel tank included a large clear stripe as an instant fuel gauge because the machines would require a fuel stop during the 200-mile race.

The frames retained the 29-degree steering head angle but were narrowed at the base of the fuel tank. The forks were machined leading axle Marzocchi, providing around 100mm of travel, with standard length (305mm) Ceriani shock absorbers.

Many 750 GT parts were modified and adapted for the racer, such as the front 278mm Lockheed discs and the machined production 38mm leading-axle Marzocchi fork. Unique to the racer was a rear 230mm disc, and 18-inch WM3 Borrani wheels front and rear. As there were only left side Lockheed calipers in stock for the 750 GT, three left-side calipers were adapted for the racers. After the test at Modena a hydraulic steering damper was also installed, at least on Smart and Spaggiari’s machines.

The engines may have ostensibly looked standard but these were also special race motors. Taglioni took early production 750 sand-cast engine cases rather than the production type used at that time. These were heavier, but Taglioni considered them stronger. Inside were re-routed oil galleys, welded-up bosses for external oil cooler lines, and cooling fins shaved to allow the right-hand exhausts to fit more snugly.

The crankshaft incorporated lighter solid billet con-rods with strengthening ribs around both the little, and big-ends, higher ratio straight-cut primary gears with a drilled clutch basket and a close ratio five-speed gearbox. To reduce reciprocating weight the flywheel and alternator were removed and the pistons a Mondial higher compression slipper type.

Also setting the racer apart were desmodromic cylinder heads, the ports carefully welded up, enlarged and finely polished to flow gases through the 42 and 38mm valves. The desmodromic camshafts providing a claimed 13mm of inlet valve lift, the engine was safe to 9,200 rpm. The total loss points ignition system featured twin spark plugs per cylinder, the additional 10mm Lodge spark plug allowing ignition advance to be cut back to 34 degrees before top dead center.

After his experience with electronic ignition failure on the 500 GP bikes during 1971 Taglioni wasn’t prepared to risk it at Imola. Taglioni was also worried about heat build up and installed an oil cooler in the front of the fairing cooling oil to the cylinder heads, also mounting the ignition condensers on the front frame down-tubes, away from the heat of the engine.

With a pair of the new generation Dell’Orto PHM 40mm concentric carburetors without chokes, Taglioni claimed the power was 86 horsepower at 9200rpm, but the broad spread providing with 64 horsepower at only 6000rpm.

In many respects the Imola machines were designed for one race only. At that time Imola was a very fast old style circuit around the hills at the back of the old township, primarily on closed-off public roads. As there was only one tight right hand corner (the Aqua Minerale), the kickstart and kickstart shaft were removed and a close fitting exhaust pipe installed on the right.

The left pipe was high-rise and as Imola was a high speed circuit the long 60-inch wheelbase wasn’t considered detrimental. The dry weight was 292 pounds, and despite the rather non-aerodynamic fairing they were reputed to pull the tallest available gearing, achieving around 169mph at the bottom of the hill and through the full throttle Tamburello corner.

Seven bikes were taken to Imola, in a specially constructed glass-sided transporter, (2 #16, 2 #9, 2 #39, and #45) with Spaggiari setting the fastest time in practice on the Friday, and along with Smart was fastest again on the Saturday. Ducati went into the race full of confidence, with Spairani particularly convinced the Ducatis would win. Before the race he told Smart and Spaggiari they were going to be first and second, and they were to share the prize money. They were not to dice for the lead until the final five laps, and if Smart won he would keep the bike.

On race day for the “200 Miglia Shell di Imola” at 3.1 mile Autodromo “Dino Ferrari” Imola, 70,000 spectators crammed in to see who would win the total prize money of Lire 35.000.000, at that time a world-record. The entry list comprised one of the most competitive fields ever in F750. Along with four factory Ducatis, MV Agusta provided machines for Giacomo Agostini and Alberto Pagani, and Moto Guzzi had official entries for Guido Mandracci and Jack Findlay. From England were the factory John Player Nortons of Phil Read, Peter Williams, and Tony Rutter, the BSA of John Cooper, and the Triumphs of Ray Pickrell and Tony Jeffries.

And completing an impressive array of factory machinery were the 750 Hondas of Bill Smith, John Williams, Silvio Grassetti, and Luigi Anelli, and the BMWs of Helmut Dahne and Hans-Otto Butenuth. There were also strong contenders in Daytona-winner Don Emde, Walter Villa, Ron Grant, and the Kawasakis of Cliff Carr and Dave Simmonds. And in addition to the factory teams and many of the world’s top riders was an array of more than 70 journalists from around the world, a number more appropriate for an auto rather than motorcycle event. The winner was going to be assured top publicity.

On race day the two silver Ducatis followed Agostini for four laps before Smart took the lead. Although he lost first gear early in the race Smart wasn’t handicapped and comfortably held first for most of the race. Agostini retired on lap 41 and Spaggiari then overtook Smart on lap 56. The two Ducatis circulated together, even pitting for fuel simultaneously. Smart regained the lead two laps from the end after Spaggiari ran wide at the Aqua Minerale.

Both very low on fuel and misfiring, Smart crossed the line four seconds ahead of Spaggiari who was now only running on one cylinder. Smart’s race average was 97.8mph and he shared the fastest lap of 100.1mph with Spaggiari and Agostini. It was Smart’s 29th birthday and it was arguably the most significant victory in his career. It was certainly a pivotal victory in the history of Ducati. They had proven to the world their desmodromic 750 could take on all comers and win.

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