A brief guide to Ducati history
The 750 GT and 750 Sport
The first Ducati bevel twin – and whether you call the 90-degree engine a V-twin or an L-twin is entirely up to you – was the 750 GT of 1970. It is known as the bevel twin as it uses a shaft and a bevel drive camshaft to operate the valves.
These days it seems to take manufacturers two years to deliver a new paint scheme, but back in 1969
Ducati started work at the end of the year, finished the design work in the spring, built the engine by mid-July... and just 60 days later the first 750GT was unveiled to the press. These first 750s are often referred to as round case models. The 748cc engine was essentially two Ducati single barrels with bevel drive camshafts, pressed-together flywheels, and a slight off-set between the two cylinders, placing the rear exhaust port in the cooling air as the rider rushed along. It was wet sump with the engine and gearbox sharing the crankcase.
As a 90-degree V-twin, it was blessed with great balance and little vibration.
The 750 weighed just 409lb. The 750 GT was joined in 1972 by the 750 Sport, with higher compression pistons, bigger carbs, and a sleeker look. And by sleeker look, I mean ‘the best-looking motorcycle of the 1970s’.
Ducati intended to break cover with the 750 Sport in the USA at Daytona, but when it realised that it needed 200 production models to be available to race in production categories, and that its racer had to be auctioned off after the race, it declined, deciding instead to launch at Imola. Two bikes were ridden to a one-two victory at Imola in 1972 by Bruno Spaggiari and Paul Smart, in the days when a racing win meant sales at the dealership. The duo defeated not only the race-proven Triumph Tridents of Percy Tait, John Cooper and Ray Pickrell, but also the works 750 MV Agusta of Giacomo Agostini. A handful of 750cc race replicas were sold the following year and the model entered limited production in 1974. Today those first 750cc L-twins with round case engines join Vincent and Brough Superior as part of the exclusive club for motorcycles that reach ridiculous prices at auction.
In 1975, Ducati made the 750 into an 860. This had what was to become known as the square case 864cc four-stroke 90-degree L-twin engine. The new engine first appeared in the curious squared-off 860GT, made in 1974 and 1975, which was replaced by the slightly restyled 860 GTS for 1976 to 1979. There was an electric start version called the 860 GTE. All the touring models had electric start after
1975.
It’s a big unit and sits between the two cylinders with a big alloy casing covering the drive mechanism. For the final two years, 1978 and 1979, the name was changed to 900 GTS. These had the new square casings, which were more acceptable in their time, but these days they simply don’t have the style of the old round case engines.
The 860 GT did not prove massively popular, partly because of its curious looks, so Ducati replaced it with the 900GTS which had the same engine but also a new rounder-edged petrol tank. To save money it also came with a drum rear brake, a conventional OHC engine rather than a desmo valve operation, and a new frame and swinging arm.
The 900SS
For the red-blooded sportsbike rider there was something almost as special as the uncompromising 750 Sport, the 900SS. This produced 68bhp, which might not sound a lot today, but in 1975 it was top of the shop. It featured desmo valve gear, special heads and 40mm Dell’Orto carburettors, along with a right-foot gear change and what were laughably described as silencers.
It had what were at the time stateof-the-art Marzocchi forks and shocks, Brembo disc brakes on the front and 18-inch spoked Borrani-rimmed wheels, while the tank was a 20-litre fibreglass item similar to that fitted to the previous 750SS. The first 900SS had British-made Smiths instruments and, showing off its racing pretensions, there were no indicators. There was also no electric start; something that lasted through the production run of the SS. This was a true sporting rider’s machine, and 1975 models were barely road legal in most markets.
When the 900SS was put into regular production for 1976 there were various modifications to make the bike available for sale around the world, including a leftfoot gearshift, a steel fuel tank, indicators and a revised instrument panel with reliable Nippon Denso clocks. To keep the lawmakers happy, the 1976 model also got smaller carbs and much quieter and more restrictive Lafranconi exhausts which took the power down considerably. Many owners swiftly swapped the silencers for Contis and fitted the original 40mm Dell’Ortos.
The SS was also equipped with some very Italian features, such as the roughly finished interior on the fibreglass nose fairing, a fibreglass front mudguard that didn’t quite fit the profile of the front tyre and the zip-up access to the seat hump, which provided storage just big enough for a few tools, or for a toothbrush and a clean shirt for use when heading for exotic assignations. Ducati kept developing the SS and by 1979 listed a 900SS as producing 72bhp at 9500rpm with a highly optimistic claimed top speed of 150mph. According to Ducati, the bike weighed in at just 393lb, 150lb lighter than that year’s Z1000 and just 20lb heavier than a Honda CB400 Superdream.
The 900SS (and the Darmah) was replaced by the 900S2 in 1983 with a better gearbox and a fairing that looked like the one fitted to the all-new Pantah 500, which was to become the basis for Ducati for decades to come.
Darmah SD
The Darmah arrived in 1977, pitched as an ultra-stylish everyday street bike to replace the GTS. This got an engine with a major redesign and the bike was styled by Leo Tartarini, of Italjet, with a dramatic red and white paint scheme (colouring Ducati perseveres with to this day) and gold Campagnolo wheels. Nippon Denso clocks, electronic ignition from Bosch, revisions to the lighting, gearbox, an uprated electric start with bigger battery to turn it over and a beefier alternator to make sure there was going to be power there next time you pushed the button. There were more resilient double-skinned exhausts, too.
Curiously there was a steering damper fitted as standard, which seemed out of place on a fine-handling Ducati, and a heavily revised frame. A classy black and Gold Darmah Sport with Conti silencers and 40mm carbs was sold alongside it.
The Mike Hailwood Replica
Following Mike Hailwood’s triumphant return to the TT in 1978 Ducati made
500 Mike Hailwood Replicas – rebodied 900ss twins that came with a certificate of authenticity.
The MHR was such a hit that once the first 500 had been sold, a Mk2 version went on sale in series production, with a revised fairing that allowed access to the engine without completely taking the fairing off. Later there were quieter silencers and a metal (rather than fibreglass) petrol tank as standard. There were then cosmetic additions like side panels, a new gearbox, and eventually – and to many a rider’s relief – a hydraulic clutch. The MHR was rebranded the 1000 Mille in 1984 and this was the last bevel drive Ducati twin, surviving until 1986, and a great way for the bevel twin to bow out.