VOL. 53 ISSUE 34 AUGUST 30, 2016 P105
In 1965, Honda unveiled an incredible machine,
one that demonstrated just how far Honda engineers
could reach beyond convention to produce a
winning design. Boasting five cylinders with a bore
measuring a miniscule 34.0mm and a stroke of
just 27.5mm, this machine had one of the smallest
cylinder bores Honda had ever attempted, and it
revved to an unheard-of 21,000-rpm redline. Into this
1.33 inch diameter cylinder Honda stuffed four tiny
valves and a centrally located spark plug. The next
year, Honda engineers made minor changes to the
bore/stroke figures, raising the redline to 21,500 rpm
and creating the RC149 shown here.
Team technicians noted that these engines were
among the most challenging of all Honda race
bikes to wrench on, not because they weren't built
well; they were incredible. The problem was they
were so small your fingers felt like huge sausages.
And if you tried to lap a valve the usual way, you'd
twist the valve head right off.
With 34 horsepower sent through an eight-
speed gearbox, the RC149 was good for more than
130 mph. In 1966, Honda won at Hockenheim in
West Germany, Sachsenring in East Germany, Brno
in Czechoslovakia, Dundrod in Ulster and Monza in
Italy, beating the two-stroke-mounted competition
for the world championship. That may have defined
the four-stroke versus two-stroke argument, but the
debate raged on for one simple reason: That was
the last year Honda's exotic works bikes contested
the 125 Grand Prix class.
Sponsored by Honda Financial Services. Learn how to finance your next Honda powersports product at hondafinancialservices.com.
"IN 1961, 1962 AND 1964, HONDA
FOUR-STROKES WON THREE 125CC
WORLD TITLES, BUT BY THE MIDDLE
1960S TWO-STROKES HAD EVOLVED
INTO AN UNDENIABLE FORCE."
