1966 becomes the absolute top year for Honda. They win the manufacturers' world championship in all five classes, for this year they also compete in the 500 cc class, and individual world championships in three classes. It is a unique fact, a record still standing today. Although during the years 1958-60, MV also won the manufacturers' title in all the classes they contested, there were only four classes then – and the competition of the MVs was weak, not to use the term non-existent.
This year Mike Hailwood, arguably the greatest motorcycle racer ever, joins the Honda team as a works rider (his participation and resulting first world championship 250 cc in 1961 was as a privateer, with the Hondas on a loan basis). After Redman's retirement, Stuart Graham, son of the famous Leslie Graham, joins the team to assist Hailwood.
In the 50 cc there's fierce competition between Taveri and Bryans on their Hondas, and Anscheidt, after the withdrawal of Kreidler, on a Suzuki twin. After the one but last GP of the season, the Isle of Man TT (this year one but last because strikes in
In the 125 cc class, the competition for Honda this year comes from Phil Read and Bill Ivy on Yamahas, not from Suzuki. Taveri takes the title, with Ivy second and
In the 250 cc class, Redman and Hailwood have to defeat the Yamaha four cylinders of Read and Ivy. Although the Yamahas are slightly more powerful with 60 bhp, the combination of Hailwood and the Honda six is so superior, that Hailwood wins the first seven races and is already world champion halfway through the season. In total he wins 10 of the 11 races this year. Read is second and Redman, who breaks his arm in Franchorchamps and retires from racing, is third. In the manufacturers' standing, Honda is first, followed by Yamaha, MZ and Bultaco.
In the 350 cc class, Hailwood wins the title with six victories, Agostini is second with three wins, and Renzo Pasolini (Aermacchi) is third. Honda wins the manufacturers' title, followed by MV Agusta, Aermacchi and Jawa. The 500 cc becomes a different story. Redman, who has decided that this will be his last season, wants to round off his career with a 500 cc world championship, so Hailwood will concentrate on the 250 and 350 cc, and Redman on the