Ducati 450 R/T
Rare Ducati dual purpose desmo single
Engine number: DM450 454137
Although we now associate Ducati with state-of-the-art sports bikes, fifty years ago things were very different. Ducati’s largest capacity motorcycle in 1970 was a 450 and their most popular model the Scrambler. As a result, Ducati saw their competition future as much in enduro competition as in road racing. Throughout the 1960s and early 1970s the US distributor Berliner largely dictated Ducati’s line-up, and following the poor sales of the 450 Mark 3 street bike Berliner was convinced the future lay in off-road motorcycles. And while the 450 Scrambler was a reasonably successful attempt at creating a dual-purpose motorcycle with street orientation, Berliner wanted a more effective dirt motorcycle to take on motorcycles like the BSA 441 Victor. During 1970 Berliner persuaded Ducati to develop the 450 R/T, and it was sold in the US as an off-road machine, with a kit providing street equipment.
The 450 R/T engine was the same 86x75mm bevel-drive overhead camshaft desmodromic unit as fitted to the 450 Desmo. This included the same quality components such as polished valve rockers. The compression ratio was 9.3:1 but setting the R/T engine apart from other Desmos was a compression release valve on the right, behind the bevel gear camshaft drive. The rear oil return line was kinked around the compression release. The 6-volt electrical system included a flywheel magneto, with points and coil ignition, and carburetion was by a Dell’Orto VHB 29 A carburettor. The standard exhaust was an open high-rise pipe, barely street legal anywhere but a single or dual muffler (as on the ISDT bikes) was also available. The power was 38 horsepower at 6,500 rpm.
A completely new frame was designed for the R/T, this sharing several features with the 750 GT frame developed at the same time. While retaining a single downtube like the other singles, two horizontal tubes from the subframe reinforced the backbone and steering head, much in the manner of the Norton Featherbed that Ducati’s engineer Fabio Taglioni so admired. Four upper shock absorber mount points were provided, the most rearward placing the units almost vertical and providing the most forward weight bias. Moving the upper mount forward angled the shock more, providing more leverage and a softer action. Chain adjustment was by a unique snail cam rear wheel adjuster and also included was a chain oiler, consisting of a plastic bottle with a valve, mounted to the frame tube above the chain. The front suspension was a longer 35mm Marzocchi fork with a pair of Marzocchi shock absorbers at the rear. Other specific components included 21 and 18-inch aluminium Borrani wheels rims, and the small 160mm Grimeca brakes of the 160 Monza Junior. Although suffering from a long 1,450mm wheelbase and hefty 128kg dry weight, the 450 R/T was a much more effective off-road motorcycle than the Scrambler.
As delivered from the factory in 1971 the 450 R/T was rather idiosyncratic. The delineation between racing and leisure use was blurred and even when fitted with street equipment the rudimentary electrical system didn’t include an engine stop or ignition switch. The method recommended in the owners’ manual was suitably vague, stating, “To stop the engine, incline the motorcycle.” But the new frame and improved suspension allowed the 450 R/T to be the best handling off-road Ducati yet, and a genuine alternative to the BSA 441 Victor. The R/T was elegant and impressively styled, but was primarily only available in 1971 and 1972. With only 422 manufactured, most of these sold in the US, it is a very rare model.
This 1971 Ducati 450 R/T is a US import and is presented in very original condition. In the interest of safety an engine kill switch has been fitted, while street equipment includes a headlight and taillight. The exhaust has been wrapped to prevent leg burns, the decompressor works, the carburettor includes the correct jets and the engine has been checked for spark and compression. It was running before storage a few t=years ago. The fin on the bottom left of the sump is chipped. We are informed by the vendor the bike is in good running order.
This motorcycle is sold unregistered.
