A cikin 1970s, Honda ya ƙirƙiri wani sabon injin tare da pistons oval don yin gasa a cikin Campeonato Mundial na Motovelocidade, a halin yanzu MotoGP. Aikin NR500 ya nemi shawo kan manyan injunan bugun bugun jini tare da maganin bugun bugun jini hudu. Wannan yunƙurin ya fito ne daga mai kafa Soichiro Honda, wanda ya ƙi injunan bugun bugun jini biyu saboda yana ɗaukar su masu hayaniya da rashin aiki. Injin 500cc V4 ya karɓi pistons na oval don ba da damar bawuloli takwas a kowane silinda, jimlar bawuloli 32 da filogi takwas.
An fara fara wasan ne a Grã-Britain GP a shekarar 1979. Baburan biyu da suka shiga ba su kammala gasar ba kuma suna bayan abokan hamayyar su da bugun jini. Iyakan ƙa’idodin a lokacin sun taƙaita shi zuwa silinda huɗu da 500 cc, yana tilasta Honda don neman matsananciyar revs. Da farko injin ya samu kusan 100 hp a 16,000 rpm, amma burin ya kasance 130 hp a 23,000 rpm don dacewa da ikon masu fafatawa.
Kalubalen fasaha na aikin NR500
Pistons masu kaifi suna buƙatar zobba na musamman don cikakken hatimi mai siffar oblong. Machining yana buƙatar mafi ƙarancin haƙuri, tura fasahar lokacin zuwa iyaka. Cada piston yana da sanduna masu haɗawa guda biyu don daidaita motsi, ƙara nauyi da taro mai ma’ana. Dogayen fil ɗin sun sha wahala daga jujjuyawa a ƙarƙashin manyan juyi, haifar da matsalolin dorewa.
Honda ya ci gaba da haɓaka a cikin yanayi masu zuwa. A cikin 1981, direban Freddie Spencer ya sami sakamako mafi kyau, ya ƙare na biyar a Grã-British GP kafin ya yi ritaya saboda gazawar injiniya. Keken ya sami nasara a abubuwan da suka faru kamar tseren kilomita 500 Suzuka a 1981 tare da Kengo Kiyama. Apesar na ci gaba, ƙarin nauyin injuna mai rikitarwa ya hana daidaiton gasa.
Juyin injiniya da canzawa zuwa bugun jini biyu
Ingantattun nau’ikan injin, kamar 2X a cikin 1982 da 3X a 1983, sun sami 135 hp da 130 hp, bi da bi. Injiniyoyin sun haɗa ƙananan ƙarfe kamar magnesium da titanium don rage nauyi. Clitch ɗin siliki ya fito azaman sabon abu don sarrafa jujjuyawar juyi. Honda ya watsar da aikin NR500 a farkon 1982, yana mai da hankali kan silinda uku, NS500 mai bugun jini, wanda ya lashe taken duniya a 1983.
Sabbin abubuwan da suka dade a cikin babur
Aikin ya yi amfani da ingantattun fasahohin injina da manyan kayan aiki. Rikicin siliki da cokali mai yawo ya zama ruwan dare akan babura na zamani. Darussa daga NR500 sun yi tasiri ga haɓakar injunan Honda V4 a cikin gasa na gaba.
Sigar titin NR750
A cikin 1992, Honda ya ƙaddamar da NR750 a matsayin ƙayyadaddun bugu na hanyoyin jama’a. Produzida a kusan raka’a 300, babur ɗin ya yi amfani da pistons elliptical tare da lanƙwasa gefuna kuma ya kai 125 hp a 15,000 rpm. Babban farashi, wanda ya yi daidai da kusan dalar Amurka 60,000 a lokacin, yana nufin an ƙaddara shi ga masu tarawa. Hoje, samfuran da ba kasafai suke kaiwa ga tsada ba a gwanjo.
NR750 ta ba da girmamawa ga aikin tseren kuma ya nuna yuwuwar fasahar daga kan hanya. Zane ya haɗa da allurar lantarki da manyan abubuwa masu aiki.
Legacy na fasahar piston oval
Jajircewar Honda wajen ƙin yarda da ƙa’idodi ya nuna tarihin hawan babur. Apesar duk da rashin cin gasa, NR500 ya tabbatar da cewa sabbin abubuwa na iya haifar da ci gaba mai dorewa. Kwarewar ta yi tasiri ga tsararraki na injiniyoyi kuma ta ba da gudummawa ga rinjayen alamar daga baya a nau’ikan bugun jini huɗu.
