After introducing the four-cylinder CB750 in 1969, Honda 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 four-into-one exhaust system that snaked around the frame, converging into a single muffler on the right side of the bike.
The four-stroke CB400F did not have the acceleration of the competitions two-strokes 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.
