The Honda CX500- Classic motorcycles

"First into the Future!" Coming from anyone else, those words would just be more tired huckstering. But coming as they did from Honda's ad men announcing the new-for-1978 Honda CX500, they demanded at least a bit of attention.

Honda CX500

Claimed power: 48hp @ 9,000rpm

Top speed: 106mph (period test)

Engine type: 497cc overhead valve, liquid-cooled v-twin

Weight (dry): 441lbs

MPG: 45-55

Price then: $2,398 (1979)

Price now: $700 - $1,700

“First into the Future!” Coming from anyone else, those words would just be more tired huckstering. But coming as they did from Honda’s ad men announcing the new-for-1978 Honda CX500, they demanded at least a bit of attention.

In today’s world of massive, 1,800cc cruisers and 150-plus horsepower sportbikes, it’s easy to forget that middleweights once ruled the road. While there were plenty of big bikes around in the late Seventies, the middle ground of 400cc to 650cc machines was a hotly contested category where Japan’s Big Four pitched their wares to mostly newer, younger riders. By 1977, Yamaha offered four mid-sized machines in two- and four-stroke guise, Suzuki had no less than seven, Kawasaki six and Honda four.

The beefiest of Honda’s middleweights was the CB550 Four. A smooth, capable machine based on the Honda CB750 introduced in 1969, it was decidedly old-school and hardly the machine to entice a new generation of riders. Enter the Honda CX500.

Moving forward 

Keen to preserve its reputation as a pioneer in motorcycle design, a reputation garnered most notably by the CB750 and the water-cooled, horizontally-opposed GL1000 introduced in 1975, Honda assigned the task of designing a new middleweight to Shoichiro Irimajiri, the man responsible for the Honda GL1000 and, later, the legendary six-cylinder Honda CBX.

Working from a clean sheet, Irimajiri and his team came up with a machine that drew almost nothing from the past and instead looked to the future of motorcycle design. What they came up with was unlike anything ever built by Honda: a water-cooled, shaft-driven V-twin. Water-cooling was hardly new, but it had never been applied to a V-twin. The same with shaft drive, but so far Honda had only used it on the massive GL1000. Yet Honda had never produced a V-twin, and this was to be a twin like no other.

To begin with, while everyone was singing the praise of overhead-cam engines, the 48hp CX500 made do with simple pushrods. This kept the engine height low and dispensed with the complexity of running separate cam chains to each cylinder. To make things interesting, Irimajiri twisted the heads 22 degrees inboard to pull the carbs in closer to the middle of the bike and out of the rider’s way. This had the benefit of splaying the exhaust pipes out for a stronger visual statement of power.

To help lower the center of gravity, the counter-rotating (to fight the longitudinally-mounted engine’s twist under power) five-speed transmission was located just below and to the right of the engine. All of this was hung as a stressed unit from a spine frame, supported by standard telescopic forks at front and adjustable shocks at rear. Importantly, the CX500 was the first production bike equipped with tubeless tires.

Source: motorcycleclassics.com