Challenged by fast-changing times Honda responded with a series of small-cube bikes like the Honda CB175 that would set the factory’s tone for decades.
When Honda first started importing motorcycles into North America at the end of the 1950s, the bikes looked quite unlike the British and American machines of the day. Honda made extensive use of pressed steel in the construction of its frames, fenders and leading-link forks. The early Benlys and Dreams even used a single pressing as a combined backbone frame and rear fender. To Joe Biker, who was used to frames and forks made of steel tubes, the aesthetics of the early Hondas were…challenging.
Honda soon realized that their premium sporting bikes needed to get with the program, and the first of their motorcycles to use a pressed steel spine (mostly hidden under the gas tank) and more conventional frame tubes were the CB72 and CB77 “Superhawk” of 1961. And while pressed-steel continued to be the frame of choice for Honda’s touring CA range and smaller displacement machines, the future looked to be in bent tubes.
So when the sporty CB160 twin arrived in 1965, some of the frame technology (and many other key features of the bigger bikes) was incorporated in the smaller capacity sports range. It was the beginning of a dynasty that would last until the end of the 1970s.
The CB160 set the course with a stroke of 41mm, a dimension that would endure through the Honda CB175 and CB200 until 1979. The CB160’s pistons ran in 50mm bores for a capacity of 161cc, fed by a single overhead cam operating two valves per cylinder, and driven by a central chain.
The 360-degree crankshaft ran on four main bearings, and with a compression ratio of 9:1, the CB160 would spin to 10,500 rpm for a maximum output of 16.5 hp at 10,000 rpm. The crank drove a spur gear primary with a wet clutch and four-speed gearbox to a chain final drive.
The engine was still suspended from a pressed-steel spine, but the rest of the frame and sub-frame were now built-up from tubes. A conventional telescopic fork replaced the leading-link design of the touring Benlys, and the rear swingarm was now also fabricated from steel tubes instead of pressed from sheet and welded. The CB160 ran on 18-inch wheels with a twin leading shoe front brake. With a dry weight of under 300 pounds, the CB160 would cover the standing quarter in under 19 seconds and run on to an estimated 75 mph.
But more cubes (and more power) are always better. So for 1968, Honda announced a 175cc version of the “Chicken Hawk,” as it had become known. Their first attempt at the 175 was little more than a CB160 bored out to 52mm and with five gears instead of four, 9:1 compression and a pair of 20mm Keihin carburetors. But the K0 retained the smaller bike’s forward-leaning cylinders. The Honda CB175 K0 was sold in Canada, Europe and Australasia as a 1968 model, but never made it to the US (though a CL175 K0 street scrambler was sold in the US). Instead, Honda revamped the styling of the CB175 twin, starting with the engine. The result was the 1969 CB175 K3.
Although the K3’s internals were common to the K0, the crankcase had been reconfigured so that the cylinders were more upright. Styling was considerably revised too: the CB160’s characteristic “toaster” gas tank was replaced with a more modern looking squared-off teardrop shape; gone was the headlight nacelle and integrated tach/speedo in favour of paired instruments mounted on the top triple tree; and straight tapered mufflers replaced the cigar-shaped items from the earlier bikes. Fenders and chainguard were chrome plated instead of painted.
The powertrain slotted into a new frame with a pressed-steel spine and a single front downtube that split into a dual cradle underneath the engine. Finished in a choice of Candy Blue or Candy Orange with white paneling, the K3 looked the business.
During 1969, two slightly different versions of the K3 were produced: the early version featured the brand name in the lower, white-painted panel on the gas tank; the later version had “Honda” in a larger colour-contrast panel. And the later versions also got a pleated rather than plain-topped seat.
The CB175 was quick too, boasting 20 hp at 10,000 rpm and at just 264 pounds dry it would accelerate to 60 mph in under 10 seconds and go on to more than 80 mph, while returning fuel consumption that could better 60 mpg. It’s not surprising that when the oil crisis hit in 1973, fuel-starved drivers snapped up Honda CB175s as alternative transportation.
The CB175 received minor cosmetic changes over the next four years, especially with the 1972 K6 model, which received a new gas tank and side covers. But the K7 would be the last of the 175s. In 1973, the Honda CB175 was phased out in favour of the CB200.
Running alongside production of the CB160 and CB175 were “street scrambler” versions, the CL160 and CL175. Mechanically, the CL160 was identical to the Super Sport street version except for the omission of an electric starter, but with cosmetic and ergonomical changes, such as high-level exhaust with heat shields on the left side of the bike, and cross-braced motocross style handlebars. The CL versions were heavier than the CBs, and so performance was marginally compromised.
Like the Honda CB175, the CL175 was produced for 1968 as the K0 with the forward-leaning cylinders of the CL160, but unlike the CB175 K0, the CL was imported into the US. For 1969-70, the K3 model sported a high-level front fender, but this was deleted on the K4.
Like the CB175, the CL ran until the K7 model of 1973, by which time, the CL had also adopted the CB’s electric starter. A limited edition run of the CL160 (CL160D) with electric start was produced in 1977-78.
The final iteration of the CB 125/160 line was the CB/CL 200, which ran from 1973-79. A further stretch of the bore to 55.5mm gave 198cc, and the front brake became a mechanically-operated disc. All CB and CL200s had electric/kick starting. With little extra weight (still under 300 pounds at the curb) and a claimed crankshaft output of 20 hp, the CB200 was capable of over 80 mph, would cruise comfortably at 60-70 mph while still returning over 55 mpg.
By Robert Smith Canadian Biker Issue #329