The Evolution of the Ducati Desmo !

Ducati’s first Desmo V-twin was the air-cooled SOHC bevel-drive design that powered Paul Smart to victory in the 1972 Imola 200.That was its competition debut.

It also took Mike Hailwood to his legendary comeback win in the 1978 Isle of Man TT. Replaced by the belt-driven sohc Pantah motor, the Desmo ceased production in the early 1980s. Since then, parts for the thousands of bikes built with this engine have essentially dried up.

Now the world’s leading Ducati bevel-drive engine specialist – Vee Two Australia in Nannup, WA – has addressed the issue by developing a brand-new air-cooled bevel-drive Desmo V-twin engine. Unveiled by company owner Brook Henry and Vee Two’s general manager Andrew Cathcart at Australia’s annual Broadford Bike Bonanza; when fired up the prototype drowned out the circuit’s pits with its incredible sound.

Built From Original Plans

The Vee Two Ritorno Twin (Italian for ‘comeback’) measures 88mm x 74.4mm for a capacity of 904cc, and in racing form is expected to deliver around 120bhp with 63lb-ft of torque. It is in fact a modern re-creation of the ultimate bevel-drive Ducati Desmo V-Twin engine, re-manufactured for sale using the original drawings supplied with the approval of the Ducati factory.

It’s an externally faithful reproduction of the factory NCR race motor used by Mike Hailwood to win the 1978 Isle of Man TT, with the crankcases and other major components sandcast in high-strength heattreated aluminium, with the many external covers cast in magnesium.

While the engine is historically authentic externally, all the internals have been manufactured using modern materials and up-todate design technology,” says Andrew Cathcart.

“But all parts are interchangeable with existing bevel-drive engines, so Ducatisti around the world whose bikes are off the road because they can’t source spare parts for them, will now be able to do so from Vee Two Australia. This design is the ultimate evolution of the bevel-drive Ducati race engine.”

We have put together this first prototype engine as a mule to allow us to commence our testing regime,” says Brook Henry.

“Over the next 12 months we will extensively develop the motor with the aim of providing both reliable interchangeable streetbike components, and an excellent platform to go racing in the Post- Classic Period 5 class here in Australia, or in Vintage Superbike and the air-cooled Pro Twins class in the USA, Japan and Europe.”

The History of the Project

After the desmo V-Twin’s successful debut in 1972, the new government-appointed manager of Ducati, Cristiano de Eccher, shut down the factory race operation as an unnecessary luxury. Eager to continue his policy of using racing as a means of developing new customer streetbikes, Ducati technical chief Fabio Taglioni skirted this by designating the nearby NCR tuning shop – recently opened by former Ducati GP race mechanics Giorgio Nepoti and Reno Caracchi – as Ducati’s satellite race team, although all the engines used in NCR racebikes were the product of the Ducati factory’s technical department.

After Steve Wynne – owner of the UK’s largest Ducati dealer, Sports Motor Cycles – persuaded Mike Hailwood to race a Ducati at the 1978 Isle of Man TT after a six-year absence, he requested the Ducati factory’s support. He was supplied with two prototype motors – an evolution of the existing production engine – manufactured by NCR to the drawings supplied by Ducati that form the basis of the Ritorno design. Hailwood duly won the race with one of these engines, and on the back of this success Ducati management decided to bring it to production as an updated replacement for its existing bevel-drive motor.

A pattern maker was commissioned to start making the requisite moulds for the new engine castings, again using these drawings. But before this could be completed, the government managers then running Ducati decided to start winding down motorcycle production in favour of diesel motors, and this new engine project was scrapped in favour of maintaining the current production bevel drive design in the short term.

That’s one reason why Mike Hailwood’s 1979 Ducati TT F1 racer – on which he finished fifth in the TT after a troubled ride – was fitted with a less powerful modified wet clutch streetbike motor.

However, these partially finished moulds were discovered in the early 1990s by a retired Italian engineer who wanted to create a totally faithful replica of the Hailwood TT bike for his own personal satisfaction.

He struck up a deal with Ducati management to obtain an official copy of the factory drawings, signed out by Ing. Gianluigi Mengoli, Ducati’s head of engineering at the time. In due course the company acquired the complete replica Hailwood bike that resulted, in return for which he was permitted to use the engine drawings for commercial purposes.

Some years later, Vee Two Australia purchased the entire project including patterns, moulds, drawings and various sets of proof castings, and has now developed the Ritorno replica motor based on this design.