I have seen quite some variations on engine design in my search for data, but this is something that stopped me in my tracks. When I was looking for some specs, I stumbled upon a picture that at first look seemed a trick made in Photoshop. But to my amazement, it is legit! Honda made for the Honda NR750 oval pistons!
In the picture above you see the oval pistons in question. This is one of four (!) pistons in this engine block which you can see in the picture below.
The Big Four of the Japanese motorcycle industry (Yamaha, Kawasaki, Suzuki, and Honda) are engaged in a bitter struggle for technological supremacy . The majority has chosen to produce mass-market: Yamaha offers the FZR1000, Kawasaki has its ZX-7RR and Suzuki-with models like the RGV250 -markets replicas of its Grand Prix racers. Honda, on the other hand, has chosen a different route by opting for more realistic mass-market models while building its high technology superbikes in homologated limited editions.
After the fabulous RC30, a 750cc replica of its victorious endurance racers, the latest in this vein is the NR750, the most advanced superbike ever built. Its story started back in 1979 when Honda returned to Grand Prix racing with a four-stroke bike.
That original NR was a failure, despite Honda's determination to make it work, and it was replaced by a two-stroke racer. The idea of a V4 with oval pistons was conceived by the brilliant engineer S. Irimajiri, who had earlier created the 1966 RC166 250cc GP racer and the 1978 CBX1000 production six-cylinder. Irimajiri returned to the idea in 1990 with the NR750,the ultimate V4. It combined Honda's most advanced technology with the wide use of exotic materials.
In 1992 Honda produced around 300 street versions of a 750cc model, the NR (often mistakenly referred to as the NR750), with a 90-degree V angle, the bike became the most expensive production bike at the time when it was selling for $50,000 and with the rarity, they nowadays rarely change hands.
Goldie 2013-11-02 19:17
Ik heb vroeger nog zo'n ding, nieuw, zien staan bij Safe Rotterdam, was altijd leuk om daar te kwijlen. Zijn al een tijdje failliet volgens mij. Groet