NR technology, the failure that HONDA presented as success!!...
In 1992, HONDA launched the NR 750. This model has the unique feature of featuring an engine (750cc) with "oval" pistons and was promoted by the brand as the ultimate exponent of technology. Interestingly, at the very moment when HONDA announced the limited production, between 300 and 800 units, according to the sources, it assumed that the NR adventure was over. I have always been of the opinion that good solutions are copied!... "Oval" pistons are such a good technology that even HONDA, who created it, doesn't want it... This motorcycle was sold for 50,000.00 USD + taxes. Selling at this price a 750cc motorcycle, with about 120 hp, dry weight of 223 kgs, only seat for the driver (a racing characteristic...) and a dynamic behavior very similar to the HONDA VFR 750 of the time, regardless of the pages written in favor of its - abandoned - technological vanguardism, it always seemed to me like a twisted 'marketing'... Unlike the original engines, the pistons on the commercialized motorcycle had a slightly elliptical shape, while in the competition prototypes the pistons were made up of two straight segments with two semi-circles at the ends.
The origin of NR (or "never ready"...)
HONDA started its presence in the World Championship in 1959 and from then until 1967, inclusive, it has positioned itself as one of the leading brands in the world sports scene. Until 1967, inclusive, the technical regulations of the various classes were quite permissive with regard to the number of cylinders and speeds that the engines could have. So, in the pursuit of performance, it was a good strategy to increase the number of cylinders and speeds. From 1968 onwards, the maximum number of speeds allowed became 6 ratios and the maximum number of cylinders became 4 for the 500cc. Thus, 2T engines gained prominence: they reached a greater specific power, were lighter and cheaper to produce. At this point, HONDA refused to adapt to the new circumstances and abandoned this championship as it understood that the development of 2Ts should not be favored. This option was also commercially justified, since, unlike HONDA, other Japanese manufacturers were more committed to 2T engines than to 4Ts, mainly in smaller capacity engines. Accusing the lack of sport promotion at this level, in 1979 HONDA returned to 500cc, stubbornly with a 4T engine... The logic behind the design of the pistons is justified by the fact that with this format, in each combustion chamber there is an available area corresponding to that of two pistons... So the intention of the design was to produce a fake 8 cylinder, or an 8 cylinder disguised as a 4 cylinder (two connecting rods per piston and 8 valves per cylinder)... What on paper seemed like a great idea, in practice was a disaster that, after a lot of investing, HONDA abandoned and, since then, nobody wanted to take it anymore!...
In this regard, Toshimitsu Yoshimura (one of the designers of this technology) said: "When I look back, I'm not sure if we were working on cutting-edge technology or just obsessed with crazy ideas." As if the engine's beak wasn't enough, in the initial project the bike also featured a revolutionary monocoque chassis that also proved to be a fiasco. The NR 500 in two different versions regularly participated in the World Championships between 1979 and 1981. In 1982 there was a third version that never got to compete at the highest level. Takazumi Katayama's 13th position in the 1981 Austrian GP was the most relevant result of a bike that many riders passed through without any being able to prove the HONDA's logic. The bike also participated in some non-championship competitions, Freddie Spencer played the most relevant role at this level, leading for a few laps a qualifying heat at Laguna Seca/USA in 1981, in the same year Kengo Kiyama won a national competition at Suzuka /Japan. From 1982, HONDA produced, like the other competing brands, a 500cc/2T that immediately proved to be competitive (the NS 500 3 cylinders 2T). From that time, a 750cc prototype was produced, aesthetics and chassis very similar to the RC30, with this technology that running in tests, during the 80's, of the Japanese Endurance Championship, without being able to score for the championship because it is not derived from series as required by the regulation of this modality, he managed, in this scenario, prototype versus series, some victories at the national/Japan level. In 1993, with a motorcycle derived from the NR 750 series, Loris Capirossi set, in Nardò, the record for the km launched with the mark of 299.825 km/h and the record for the 10 kms with a stopped start with the mark of 283.551 km/h. These records are still in force in a sport where the dispute is not, at the moment, very close.