After introducing the four-cylinder CB750 motorcycle in 1969, Honda Motor Company followed with a string of lighter fours featuring engines as small as 350 cc (CB350 Four, CB500 Four), and the CB400F 408 cc Four, produced in 2 models from 1975 through 1977.
For the most part, the CB400F was simply an upgraded version of the 350 model from the previous year. The most striking change was the swoopy four-into-one exhaust system that snaked around the frame, converging into a single muffler on the right side of the bike. Also noticeable were the angular fuel tank and flat cafe-style handlebars, all of which gave the bike a more racer-like look and feel than the rather pedestrian 350.
Although aimed at the sporting segment of the market, the four-stroke CB400F did not have the acceleration of the competition's two-strokes, particularly the triples from Kawasaki. But what the CB400F engine lacked in power it made up for in refinement, the small-displacement four-stroke being smoother, quieter and much more economical than the two-strokes. To help keep the engine in its power band, Honda employed a six-speed transmission—something of a rarity at the time.
The CB400F was a very successful motorcycle in club or privateer racing. Kaz Yoshima and other racers were able to take Honda's little 408cc engine up to 490cc and with the addition of other racer options, this small bore was considered a 'giant killer'.
The most noticeable difference between the two models is that the earlier one had the pillion foot-rests on the swinging fork rear suspension, whereas the F2 had them on tubular brackets attached to the frame. The later model had stripes on the tank.
|Engine||408cc transverse four|
|Bore & Stroke||51mm x 50mm|
|Compression Ratio||9.4 : 1|
|Carburetors||Four 20mm Keihin (piston valve)|
|Ignition||Kettering- coils, points, and condensors|
|Starter||Kick and Electric|
|Wheelbase||53.3 inches (1355mm)|
|Seat Height||31.1 inches (790mm)|
|Fuel Capacity||3.7 gallons, including 0.88 gallon reserve|
|Wheels||18in. Spoke Type|
|Tires||Front: 3.00S - 18 tubed
Rear: 3.50S - 18 tubed
|Brakes||Front: Single disc
|Weight||Dry: 375 pounds (170 kg)
Wet 390 pounds (178 kg)
In 1989, a new 400-four appeared, the Honda CB-1. It had nothing in common with the original except for the near 400cc displacement and inline-4 cylinder configuration.