Honda RC170 - RC171 350 Four cylinder

Racing Bikes Honda RC170 - RC171 350 Four cylinder
Class	Racing
Weight
Recommended Oil	Honda GN4 10W-40
Manuals	Service Manual

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Overview

Honda RC170 - RC171 350 Four-cylinder

Honda first competes in the 350 cc class on Man, with a 250 four cylinder bored out to 47 mm, giving 285 cc. The bike delivers 50 bhp at 13,500 rpm. Later, a new bike, designated RC171, with bore and stroke of 49 x 45 mm, giving a total capacity of 339.4 cc, is developed, used for the first time at the Ulster GP. Power output is 56 bhp at 12,500 rpm. Since there are some cooling problems, the bike gets an oil cooler behind the exhaust down pipes. Later, after some small changes, the engine is thermically OK, and the oil coolers are taken off again. The first appearance of a multi cylinder Honda 250 came at the end of 1959, when the Honda 125 made its debut at the Isle of Man Tourist Trophy. After that race Honda withdrew to its factory for a time. The prototype of the four-cylinder Honda 250 was a very coarse 35-h.p. vehicle that Japanese drivers tried out on dirt tracks. The cylinders of this motorcycle were perfectly vertical, and the distribution utilized a double overhead camshaft with bevel gear shaft. The look of the vehicle was then improved, resulting in excellent detailing. The engine was redone and the cylinders were inclined 30° forward. The new distribution was gear-operated. This four-cylinder Honda made its European debut in 1960, ridden by the Australian Tom Phillis and the Rhodesian Jim Redman. In 1961 Honda hired Mike Hailwood, and the championship was almost too easy for him with the four-cylinder 250. The following year Hailwood accepted MV Agusta's offer to ride its 350 and 500 models, perhaps hoping to have a more exciting season. This compelled Honda to fall back on Redman, who won the championship in 1962 and 1963 in the 250 class and chalked up two wins in the 350 class. Motorcycle: Honda 250-350 Four-cylinder Manufacturer: Honda Motor Co. Ltd., Tokyo Type: Racing Year: 1962 Engine: Honda four-cylinder, four-stroke, with two-shaft overhead geared distribution and four valves per cylinder. Displacement 249.3 cc. (44 mm. x 41 mm.—250); 339.4 cc. (49 mm. x 45 mm. —350) Cooling: Air Transmission: Six-speed block Power: 46 h.p. at 14,000 r.p.m. (250); 54 h.p. at 12,500 r.p.m. (350) Maximum speed: Over 135 m.p.h. (250); over 140 m.p.h. (350) Chassis: Double cradle above, tubular, suspended engine. Front and rear, telescopic suspension Brakes: Front, central drum, four shoes; rear, central drum, double cam