In 1945, Japan needed an inexpensive, compact, practical mode of transportation. Company founder Soichiro Honda strove to meet the demand by attaching 500 war-surplus two-stroke gasoline engines to bicycles. By 1946, Honda had a factory in Hamamatsu building complete motorbikes. The bikes ran on turpentine, as gas was in short supply. The bikes sold well and the army surplus engine supply soon ran out, so Honda began to manufacture his own 50 cc engines.
Soichiro Honda built a modified two-stroke 50 cc engine based on the design of a small motor used by the Imperial Army to power generators. Honda built the 50 cc as an auxiliary bicycle motor and to run small personal transportation motor-bikes. The Honda Technical Research Institute perfected the engine under President Soichiro Hondas' guidance. The 1947 A-Type Honda motorbike featuring a 1/2-horsepower 50 cc engine was known as the "Chimney," as the engine smoked excessively from its turpentine fuel.
Honda motor-bikes sold very well and Soichiro founded the Honda Motor Company in 1948 to keep up with the increasing demand. In 1952, Honda introduced the F-Type Cub, outfitted with a 50 cc engine generating 1/2 horsepower. A year later, Honda was building 6,500 Cubs a month, producing 70 percent of Japan's motorized two-wheeler market. The 50 cc engine was sold as an attachment for push-bikes, or as the powerplant of the red and white Cub, called the Auto Bai by its Japanese riders.
The NS250R MC11 was introduced in 1985 and was the leading edge design destined to be the ultimate configuration for a twin cylinder 2-stroke motorcycle. It sported both an aluminium frame and swingarm, unheard of on a road-bike in it's day, along with Honda's trendy Astralight wheels.
The engine for the NS was closely based on the same design as the factory works machines, again Honda used the ATAC system similar to the MVX, but had now introduced a nickel-silicone carbide (Nikasil) coating on the cylinders for reduced friction and greater wear resistance.
1984 Honda NS 250R
The key to understanding the NS250Rs' behaviour can be found in Honda's brief history with the 250cc two-stroke streetbike class so hotly contested in Japan. Honda first entered the market two years ago with the MVX250, a V-Three patterned loosely on Freddie Spencer's 500cc GP racer.
The MVX was pleasantly torquey for a 250, but not as fast as the competition. Nor did it sell as well. So Honda reasoned that if a torquey, civilized, not-very-fast two-stroke wouldn't sell, the answer was to build the opposite- the NS250R.
1985 Honda NS250R MC11
The NS250R's design and styling was taken directly from the works RS250Rs of that era, a bike that was cleaning up in GP's and eventually allowed Freddie Spencer to win both the 250 and 500 World GP titles in the same season!
The NS250R is a flawed gem. On a racetrack or the right road, it sparkles; but on the average street, it has all the glitter of a fouled sparkplug.
The NSR 250 debuted on October 1st 1986 as a 1987 model in Japan for 559,000 Japanese Yen, dubbed the MC16 by the factory. It replaced the older NS 250 R that was getting out dated. Honda was winning with it's NSR racers so Honda released a replica version for the street. It was almost a complete replica of the factory racers. It was lightweight and quick. The engine was basically a NSR500 racer engine cut in half.
The first year NSR250's were the only 250 NSR's to have three spoke wheels. Available colors were fighting red and white at first until the release of the Terra colors in blue and white that went on sale in March of 1987. It was an amazing machine in it's day with nimble handling and awesome acceleration
Honda's 1985 NS400R was an homage to Fast Freddie Spencers' world championship in the premier (500cc 2-stroke) class. That Spencer captured the crown in 1983 was a little puzzling but that Honda made the new bike a 400cc machine was slightly weirder. No matter, the quickly became the class of it's class. And speaking of weird, the motor is a V3 with the middle cylinder being verticle and the outer two canted forward, giving the bike a slim and compact cross-section. With it's box-section aluminim chassis and Grand Prix race replica features, including a close-ratio 6 speed gearbox, and weighing only around 360lbs, this short-wheelbase unit handled beautifully, stopped well and had a smooth (for a 2-stroke) powerband owing to Honda's "power-valve" system. Truly a standout amongst the repli-racer classics.
Make Model; Honda NS 400R
Engine liquid cooled, 90°V-three cylinder, two stroke reed valve
Capacity 387cc Bore x Stroke 57 x 50.6 mm
Compression Ratio 6.7:1
Induction 3x 26mm Keihin carbs
Ignition / Starting CDI / Kick
Max Power 72 hp 52.5 kW @ 9500 rpm ( 59 hp @ t 8,500 rpm )
Max Torque 5.1 kg-m @ 8000 rpm
Transmission / Drive 6 speed / chain
Gear ratio 1st 2.500 / 2nd 1.714 / 3rd 1.333 / 4th 1.111 / 5th 0.965 / 6th 0.866
Frame Double cradle
Front Suspension Air assisted forks. adjustable anti-dive 120mm wheel travel
Rear Suspension Pro-link adjustable preload 100mm wheel travel
Front Brakes 2x 256mm discs 2 piston calipers
Rear Brakes Single 220mm disc 2 piston caliper
Front Tyre 100/90 -16
Rear Tyre 110/90 -17
Seat Height 780 mm
Dry-Weight 163 kg
Fuel Capacity 19 Litres
Consumption average 30 mp/g
Standing ¼ Mile 13.03 sec / 164.2 km/h
Top Speed 202 km/h