The CB500 production series was 1971 through 1973. In 1974 the machine was revised to a 550 and continued production through 1978. Why the change? Was it just a simple update?

1971 was of course just a couple years after the CB750's debut in 1969. Honda wanted a smaller four, which would be just their second one, and they wanted to make a splash, and do it quickly and do it cheaply. So they actually took already-existing parts from another model, the CB350 twin. This is how the CB500 came to have the same transmission and clutch as the 350. A few of the parts are even the same part numbers. The 350's trans was not the most sophisticated, not the smoothest shifting. And it seemed even less so in the 500 than in the 350 due to the 500's greater power and weight.

For 1974 Honda took the 350 clutch and trans out of the 500 and put in the 750 clutch and trans instead. Not the exact parts, but the same parts scaled down slightly; the same design. This made the CB550 a much nicer-shifting motorcycle. To draw attention to the new vehicle without saying anything about the 500's rubbery transmission, Honda took a cue from the car industry and used the new model name, made possible by a less than significant displacement increase, to present the machine as an all-new bike. And as far as the clutch and trans were concerned, it certainly was that.

The CB500's shifting is a little less sure than that of the CB550. It requires a bit more deliberation. However, if the parts are in good condition and everything is adjusted properly, and your shifting style looks like a firm, snap movement (not a jab, nudge or stomp), it shifts well enough. Few if any riders noticed any glaring shortcomings in the 175, 350 and 450 twin transmissions, after all.