1965 proves to be a year of mixed results. The Honda Research
& Development Company (which covers the racing department, said
to contain at this stage 400 engineers, technicians and mechanics)
is still heavily involved in the development of the formula 1 car,
and the motorcycles might not get the amount of attention they need.
After Franchorchamps, halfway through the season, the mechanics
return to Japan and the care for Redman's bikes is left to Nobby
The works riders this year are Jim Redman, as usual also acting
as team captain, Luigi Taveri and Ralph Bryans. Honda skip the first
GP of the season, Daytona, where Suzukis win the 50 and 125 cc classes,
and Read on the Yamaha the 250 cc. In the end, it makes no difference
for the results.
In the 50 cc class, Hondas win 5 of the 8 rounds, and Bryans
becomes world champion, with Taveri second and Anderson (Suzuki)
third. Honda also wins the manufacturers' title.
The 125 cc class is a total disaster this year. Honda start
the season with last year's 2RC146; they retire in Germany and Spain
and end up down the field in France. On the Isle of Man, the 4RC146
makes its debut. Taveri comes in second in Man, the best place of
the season(!), and comes in 5th in Holland. In East-Germany and
Czechoslovakia the Hondas don't start, in Ulster Bryans finishes
4th, in Monza again no Hondas. In the last GP of the season in Japan,
the new 5 cylinder 125 cc is unveiled, and though the bike is streets
faster than the Suzukis, Taveri has to retire with an oil leak while
Hugh Anderson (Suzuki) becomes world champion, with Frank Perris
(Suzuki) second and Derek Woodman (MZ) third.
In the 250 cc and the 350 cc, it's Jim Redman who has a disastrous
season. No start in Daytona, in Germany he falls off the 350 in
the rain while chasing Agostini on the new and very fast 3 cylinder
MV and breaks his collarbone, which prevents his start in the 250
and his participation in Spain. In France Redman retires in the
250 with gearbox trouble while leading from Read. On Man everything
goes well, and Redman wins both the 250 and the 350 ahead of Read
(Yamaha). In Assen, in the 250 it's Read ahead of Redman, in the 350 Redman
ahead of Hailwood (MV). In Belgium the 250 is for Redman, Read is
second, and it's the same in East-Germany, where Redman also wins
the 350 cc. In Czechoslovakia in the 250 Redman is third behind
Read and Duff (Yamaha), he wins the 350. In Ulster Redman falls
off in the 350 and breaks his collarbone again, and again it prevents
his participation in the 250, which is duly won by Read. Honda tell
Redman that there is no bike for him at Monza, so Redman stays home
in Rhodesia. Later it transpires that there was a bike waiting for
him – a mighty Honda blunder. In the 250 cc class Read uses here
for the first time a four cylinder Yamaha. All this bad luck for
Redman has brought Agostini on the MV, who wins easily in Finland
and Italy, so close in the 350 cc class, that the last GP in Japan
must bring the decision. When Redman puts his goggles on for the
decisive 350 cc race on the Suzuka course, a bee slips in and stings
him over his eye, that swells completely shut. To make matters worse,
only 4 of the 6 speeds of his bike are home. But a contact breaker
spring (of all things!) of Agostini's MV breaks, and Redman comes
in second behind Hailwood (MV) which is enough for the title, while
Mike Hailwood wins the 250 on a Honda six. Read becomes 250 cc world
champion, with Duff second and Redman third, Honda is second in
the manufacturers' world championship. In the 350 Redman is world
champion, with Agostini second and Hailwood third.
The RC115 has a completely new engine. See images below
Bore and stroke are now 34 x 27.4 mm, giving a total capacity
of 49.75 cc. The enclosed valve angle 72 degrees for the RC114,
it is now 56 degrees, with 24 degrees for the inlet valves and 32
degrees for the exhaust valves.
Drive to the camshafts is still with a gear train on the right
hand side, but is now taken from the clutch drive instead of from
a gear on the crankshaft, as can be seen in the first Engine picture.
What also can be seen in this picture, is that the megaphones are
not welded to the down pipes as usual for Hondas, but slipped over
them – necessary because they're made of aluminium, to save weight.
Carburettors have the flat slides.
Power output is a healthy 15 bhp at 20,000 rpm. Lubrication is by wet sump; there are nine speeds in the gearbox.
Dry weight is 50 kg – compare that with the 61 kg of the single
During the season, both high level exhausts and the normal low
level exhausts are used. The high level exhausts have the advantage
of a smaller frontal area, because the fairing can be kept narrower,
which gives less air drag. See opposite image
1965 RC115 Honda Engine
1965 RC115 Honda Engine
cc 4RC146 & RC148
1965 RC115 Honda
The 4RC146 is an improved version of the 2RC146, and nearly
identical to it – the only external difference are the shorter exhausts
of the 4RC146 (see pic 4RC146).
Power is now 30 bhp at 17,000 rpm. In actual practice, the engine
hardly ever runs well, with continual Carburation and ignition problems.
Some interesting data: the piston, as usual for Honda with two
compression and one oil scraper rings, weighs 34 g without the pin
and rings. The pin, with a diameter of 11 mm weighs 11 g. An inlet
valve has a head diameter of 14.5 mm and a stem diameter of 3.8
mm and is 74.4 mm long. Weight: 9 g. Two valve collets and the retainer
weigh 1 resp. 3 g. Nobby Clarke said they used tweezers to put the
Honda valve gear together.
The RC148 is the great surprise of 1965.
It is a five cylinder, in principle two and a half 50 cc twins.
Bore and stroke are 33 x 29 mm for a total capacity of 124 cc.
Drive to the camshafts is by gear train between the third and
fourth cylinders. Power is 34 bhp at 20,000 rpm. There are eight
speeds in the box, and the engine has wetsump lubrication.
The four exhausts of cylinders 1, 2, 4 and 5 sit in the normal
place, left and right of the bike, the exhaust of cylinder 3 sweeps
up and around the lefy hand side of the engine, crosses through
the frame, to end up under the right leg of the rider.
Dry weight is given as 85 kg.
1965 4RC146 Honda
1965 RC148 Honda
cc 3RC164 & RC165
The six cylinder, used in the Monza GP of 1964, was called the
3RC164 – a strange name, because the RC164 part refers to the four
cylinder. The same bike is used in the beginning of 1965 (see pic
It has two three cylinder crankshafts, coupled in the centre
of the engine. The general construction of the engine follows the
usual Honda practice.
Bore and stroke are 39 x 34.8 mm, for a total capacity of 249,43
cc. Valve angle is 75 degrees, 34 degrees on the inlet and 41 degrees
on the exhaust side. Spark plug size is the by now familiar 8 mm.
Of course the ignition is by transistorised system – since 1964
the contact breakers are obsolete on Honda racers. Lubrication is
by wet sump system.
The gearbox contains an eight speed cluster. The engine is no
wider than that of the RC161 four cylinder. Pic 3RC164-2 shows the
bike with the larger tank for the TT of Man in the Honda workshop
in the Castle Mona hotel on Man.
The RC165 is virtually identical to the 3RC164, but power output
is now 56 bhp at 16,500 rpm, with a red line at 17,000 rpm – short
excursions to 17,500 rpm are allowed.
The 2RC172 is practically identical to
the RC172, with detail modifications. Although the basic design is
now already several years old, the new MV-3 is still no match for
it as regards speed and acceleration.