F1 tech in MotoGP: The Aprilia RS3 Cube

Looks cool, eh? Pity the RS3 Cube never worked...

First seen at the Bologna Motor Show in Italy, in December 2001, the RS3 Cube marked Aprilia’s ambitious entry into the tempestuous world of MotoGP. Powered by a four-stroke 990cc three-cylinder engine fitted with pneumatic-valves, the 240-horsepower RS3 was supposed to be one of the most powerful MotoGP machines of its time.

Raced from 2002 to 2004, the Cube’s performance was less than exemplary. There were problems with the bike’s suspension, and its computer-controlled fly-by-wire throttle system was deemed unpredictable by riders Colin Edwards and Noriyuki Haga, with the latter crashing the RS3 Cube all of 28 times in a single season, in 2003! (Unless Haga-san was crashing the bike twice in almost every race, we suppose that figure includes crashes during practice and qualifying etc.)

So what went wrong? The RS3 Cube’s inline-three was designed by Aprilia in a technical collaboration with British engine specialists, Cosworth, who had earlier also worked with Aprilia on the RSV1000’s v-twin. ‘We chose a three-cylinder engine for several reasons. The first was that I was sure the Japanese wouldn't make a triple, and it was important for Aprilia to have something different from the others,’ said Aprilia racing team boss, Jan Witteveen, speaking to Motorcyclist magazine.

‘MotoGP rules favor three- and five-cylinder machines, and historically, the triple is more a European concept. A 990cc triple has a 330cc cylinder capacity, which is very close to the dimensions of a 10-cylinder 3.5-litre engine of an F1 car. This way, I could use a lot of technology and parts from Formula 1, which would save some development time,’ said Witteveen.

Noriyuki Haga and Colin Edwards found the RS3 Cube a right handful...

At one time, Aprilia even had plans of building a street-legal replica of their three-cylinder MotoGP machine, but when the RS3 Cube failed to do well in competition, all those plans went out of the window. A lot of the problems with the bike were down to its complex engine management and traction control systems – riders did not like the way these ‘interfered’ with their ‘normal’ way of riding.

Also, the Cube’s chassis and suspension combo did not work very well. The bike’s twin-spar aluminum frame, Ohlins shock, and 45mm Ohlins fork may have been top-spec components individually, but did not work with each other – the RS3 was prone to pulling wheelies, and there was often lack of adequate traction at the rear, a problem which was actually further compounded – rather than helped – by the Cube’s traction control system.

‘The RS3 pulls strongly from 8,000rpm and goes mental when you crack the throttle hard open anywhere above 10,000rpm grand, accelerating unbelievably fast. Your arms are yanked in their sockets and the Cube just takes off. Anywhere from 11,000rpm upward in the bottom four gears, the front wheel starts pawing the air as you shift seamlessly through the gears,’ said Alan Cathcart, when he tested the bike for Motorcyclist.

Cathcart actually liked the motorcycle, saying that ‘This is very far from being the unruly and remote-feeling rolling-laboratory-cum-two-wheeled-Formula 1 car I was expecting. Instead, it felt like a conventional race bike, but with genuine added value obtained from real-world applied electronics-with-a-purpose.’

However, Colin Edwards, who actually raced the bike in 2003, had a very different opinion of the RS3 Cube. ‘Too trick, possibly. Actually, I would not say too trick. I'm just not convinced that car technology works on motorcycles,’ he said, speaking to Superbike Planet.

Well, almost five years after Aprilia pulled the plug on their MotoGP effort, it’s perhaps too late to contemplate whether F1 tech could have worked in MotoGP, had Cosworth tried a bit harder. What matters is, Aprilia haven’t given up – they hope to be back in MotoGP by 2010 with an all-new bike. Now if only they can get Stoner to ride for them…