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Saw this bike in a book I just got for x-mas. Never heard of it. V-4, oval pistions and eight valves per cylinder.
http://www.youtube.com/watch?v=M__p0LjSOOA
This video is in German, but has great views of the engine.
http://www.youtube.com/watch?v=fW8KmTA8jfA
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I believe it has two-con rods per piston too. At the time it was sold it was the most advanced, and expensive motorcycle in the world. By a considerable margin..
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Came out of MotoGP racing development. When Honda was limited by rule to only 4 cylinders, they just made the cylinder bores oval, with oval pistons, and enough valves to be equivalent to 8 cylinders, but still technically only 4. I think ring sealing was an issue an other than Freddie Spencer winning a couple championships with the technology, it never went any further. This is by memory now, and a long time ago, so please forgive if I got some info wrong. I can research it if you like one of these days, but it was mighty Honda showing just how technological they could be if necessary.
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(12-25-2013, 03:55 AM)The ferret_imp Wrote: Came out of MotoGP racing development. When Honda was limited by rule to only 4 cylinders, they just made the cylinder bores oval, with oval pistons, and enough valves to be equivalent to 8 cylinders, but still technically only 4. I think ring sealing was an issue an other than Freddie Spencer winning a couple championships with the technology, it never went any further. This is by memory now, and a long time ago, so please forgive if I got some info wrong. I can research it if you like one of these days, but it was mighty Honda showing just how technological they could be if necessary.
In 1980, Honda was determined to be competitive w/ their 4 strokes against the dominating 2 strokes and the Grand Prix NR500 was the unsuccessful result. The paddock joke was that NR stood for "never ready" because it had multiple breakdowns before and during races. It won exactly 1 race; too heavy and too much experimental technology made for an early retirement in 1983. The street version NR750 was released in 1990 or so and extremely rare, collectable and expensive ($75,000 new).
It's my all-time pipe-dream to own.
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If I was a millionaire, I'd have an NR750 in my livingroom.
If I was a multi-millionaire, then in addition to the bike in the livingroom would be an exposed cut-away engine, showing off the pistons and valves.
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Hmm I guess Freddie won on it's replacement the NS500 two stroke.
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jeezalou, can you imagine?
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If you want to see one in flesh there is one in the Barber Museum.