He was a fiery automotive industrialist, who raced briefly in Formula 1, owned a motoring empire and even dabbled in a little coup d’état on the side. Alejandro De Tomaso was anything but boring and although he is best known for his De Tomaso sports cars, at one time he also owned Maserati, Ghia, Benelli and Moto Guzzi among other famous Italian household names. When he purchased Benelli, the motorcycle company was on its knees and in dire need of a solution to the multi-cylinder attack coming from the Japanese big four. His methods were questionable, but the bikes were beautiful and when an engine and frame from the De Tomaso era arrived at Unik Motorcycles in Portugal, the team had to work their magic. What they’ve created from the scintillating six-cylinder, is both an ingeniously engineered and an utterly beautiful Benelli Sei 900.
When De Tomaso took control of the motorcycle company in 1971, the Japanese manufacturers had come out swinging with their lightweight multi-cylinder machines and the Brits and Italians were on the back foot. As we now know, many previous powerhouses of the industry would not survive as they failed to engineer motorcycles for the new era. So, De Tomaso took a different approach, he purchased a Honda CB500 four-cylinder and instructed his engineers to “take inspiration” from what they saw; which they did, from crank to covers. And what do you know, the Italians were back in business with not only a four-cylinder engine, but a six-cylinder 750cc, the first production six brought to market.
It’s true that a number of other factories had built sixes in the past, but those were race bikes with engines completely unsuitable for commercial sale. By the time 1979 rolled around and this particular Benelli Sei 900 was sitting on a showroom floor, most of the problems associated with copying and pasting someone else’s work had been resolved.
But for Tiago and Luis of Unik, their work was just getting started, with only a bare frame and engine sitting before them. The Benelli name and the smooth symphony that is the six-cylinder engine that gives the bike its name, ‘Sinfonia’ demanded something more, and having drawn up their design, the guys knew they could deliver.
The factory frame of the Sei was actually an excellent piece of kit in its time, but fifty years since it was first developed, Unik wanted to improve it. The big issue is the back end and to solve that problem they undertook the massive task of adapting a modern single-sided swingarm from a Ducati S4R. You can’t simply bolt one in, you’re going from a twin shock setup to a monoshock, a 120 section tyre to a 190, and aligning a rear sprocket position designed for a narrow L-Twin to one now running via a super wide transverse six. But having been in the game for years, the guys have done an expert job at tackling every problem and finding a brilliant solution.
To bring the front end up to the same standard, the already super strong headstock has been given a treat with all-new bearings to swing a set of modern sport bike USD forks. The adjustable units are clamped by a massive three-bolt lower tree and the upper has been retrofitted with a set of risers and LSL bars. Braking is always going to be an issue with such a weighty engine onboard, but six-piston calipers and twin disc rotors, sent power from a radial master solve those problems. Finally to get the big Benelli rolling the guys didn’t skimp on the wheels and optioned up a beautiful set of Kineo spoked items.
The intention was always to build a monocoque-style body, but before they could begin, the factory subframe was cut off and a new shorter and more precise item was fabricated and welded to the main chassis. “We wanted to use the original tank or part of it, but in reality nothing was used, only part of the tank cover (fairing) was used,” Tiago explains. And when he says fairing, that’s what he means, as the factory bike utilised a tank cover and separate fuel cell; very ahead of its time. The rest of the bodywork the boys beautifully beat from aluminium, and from the gorgeous lines to the oil tank and Monza filler, it is simply a work of art.
The six-cylinder engine might just be a Honda Four with two extra pots, but its smooth power as the revs climb is intoxicating. By ’79 the small clutch surface intended for a 500cc engine had been fixed with better materials and heavier springs and the bank of small Dell’Orto carbs mean that power isn’t huge, but linear in delivery.
To spice this up the guys reduced the restriction of the factory airbox with pod filters and equipped the ignition with modern components. But the pièce de résistance is that incredible full stainless exhaust system with equal-length headers and a set of up-swept triple pipes on each side.
To run the whole show and keep things high-end, there was only one place to go, and the boys unleashed the Motogadget catalogue on the bike. To house the motoscope dash and the LED headlight, it was over to modern technology as a 3D drawn and printed solution was created to produce a marvellous front mask.
The paintwork could make or break the bike and the decision to go with colours inspired by Benelli, Italy and the “cafe racer culture” has produced a truly stunning finish. The look has been transferred onto the front guard, rear shock and wheels and it’s all topped off with a minimalist leather seat. Unik Motorcycles have more than lived up to their name and you have to think that De Tomaso himself would be smiling down with his charming nod of approval.
[ UNIK Motorcycles | Photography by Tiago Almeida ]