Before the advent of the CB750, the bike that changed for ever the way we think about motorcycles, Honda made its name with a succession of jewel-like four-stroke twins.
The 250cc CB72 and the 305cc Dream revved to five figures, started every time at the push of a button even in the depths of an English winter, didn't leak a drop and (in a straight line, at least) could run away from any Brit bike under 500cc.
Thirty years later Honda twins are still in production: the CD200 delivery bike, the CB250 commuter and the stylish CB500 featured here. However, while the older, air-cooled designs are served by a single overhead cam and two valves per cylinder, the 500 has water jackets around the top of the motor, twin cams and eight valves.
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Still, its heritage shows clearly in the familiar clean line of the horizontally split crankcase. From the right, especially, the motor looks surprisingly similar to the CB175 on which I learned to ride in 1969.
The power is concentrated in the top half of the rev-counter. It's an oversquare (73x59.6mm bore and stroke) parallel twin, red-lined at a dizzy 10500rpm. There's no real power band, no clearly defined point at which the motor comes "on cam", but the power is concentrated in the top half of the rev-counter dial.
It's rated by the factory at 43kW at 9500rpm with maximum torque of 47Nm at a high 8000. It'll rev well past 10 000 with no ill effects and only a tingling vibration through the foot-pegs to remind you that the CB's motor is working hard.
But such is the finesse with which this motor has been set up that it will pull, gently but evenly, on part throttle from 2500rpm in the lower gears and it will hold 55km/h in top gear at just under three.
From there it will pick up, pulling with surprising authority from 6500rpm to top out at a measured 181km/h under perfect conditions with the rider prone and 9000 revs on the clock.
It's a superb example of what can be done with a sound basic design and a little finesse.
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