Restoring and riding a 1969 CB175K3, the successor to the well-known Honda CB160.
1969 Honda CB175K3
Claimed power: 20hp @ 10,000rpm
Top speed: 80mph (est.)
Engine: 174cc air-cooled OHC parallel twin, 52mm x 41mm bore and stroke, 9:1 compression ratio
Weight (w/half tank fuel): 297lb (135kg)
Fuel capacity/MPG: 2.4gal (9ltr)/60mpg (est.)
Price then/now: $650 (est.)/$500-$2,500
Remember Trickle-Down? The theory of supply-side economics that became popular during President Ronald Reagan’s administration? That phrase could also be used to describe the development of Honda’s immensely popular range of sub-200cc twins from the 1960s and 1970s.
When Honda first started importing motorcycles into the U.S. at the end of the 1950s, the bikes looked pretty weird alongside the British and American bikes 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.
Those pressed steel frames also made their bikes seem cheap, and Honda soon realized their premium sporting bikes needed to get with the program. The first Honda motorcycles to dispense with pressed steel in favor of a more conventional tubular frame were the CB72 and CB77 Superhawk of 1961. While pressed steel continued to be the frame of choice for Honda’s touring CA range and smaller displacement machines, the future for its large bikes looked to be in bent tubes.
When the sporty CB160 (and the non-U.S. CB125) twins arrived in 1965, some of the frame technology and many other key features of the bigger bikes had “trickled down” to the smaller capacity sports range. It was the beginning of a dynasty that would last until the end of the 1970s.
The CB160 and CB125 set the course of Honda’s small twins with a stroke of 41mm, a dimension that would endure through the CB175 and CB200 until 1979. The CB160’s pistons ran in 50mm bores for a capacity of 161cc, with 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 the crank drove a spur gear primary with a wet clutch and 4-speed gearbox to a chain final drive. With a compression ratio of 9:1, the CB160 had a claimed output of 16.5 horsepower at 10,000rpm.
The engine was still suspended from a pressed-steel spine, but the rest of the frame and subframe were now built up from tubes. A conventional telescopic fork replaced the leading-link design of the touring Benlys, and the rear swingarm was fabricated from steel tubes instead of pressed and welded sheet steel. The CB160 ran on 18-inch wheels with a twin-leading-shoe front brake. With a dry weight of less than 300 pounds, the CB160 would cover the quarter-mile in about 19 seconds and run on to 75mph.
More cubes 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. The CB175K0 retained the smaller bike’s forward-leaning cylinders. The CB175K0 was sold in Canada, Europe and Australasia as a 1968 model, but never made it to the U.S., although a CL175K0 street scrambler was sold here. In 1969 Honda revamped the styling of the CB175 twin for the U.S. market, starting with the engine. The result was the CB175K3.
Although the K3’s internals were common to the K0, the crankcase had been reconfigured so that the cylinders of the K3 were more upright. The styling was also considerably revised. 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 tachometer/speedometer in favor of paired instruments mounted on the top triple tree. Straight tapered mufflers replaced the cigar-shaped items from the earlier bikes and the fenders and the chain guard were chrome plated instead of painted.
The powertrain slotted into a steel tube frame with a single front downtube that split into a dual cradle underneath the engine. Finished in 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 color-contrast panel. The later versions also got a pleated rather than plain-topped seat.
The CB175 was quick, too, boasting a claimed 20 horsepower at 10,000rpm, and at just 264 pounds dry it would accelerate to 60mph in under 10 seconds and go on to more than 80mph, while getting better than 60mpg. It’s not surprising that when the oil crisis hit in 1973, Honda CB175s were snapped up by fuel-starved drivers 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 1973 K7 would be the last of the 175s. For 1974, the CB175 was phased out in favor 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 ergonomic changes, such as a 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 CB175, the CL175 was produced for 1968 as the K0 with the forward-leaning cylinders of the CL160. Unlike the CB175K0, the CL175K0 was imported into the U.S. For 1969-1970, the K3 model sported a high-level front fender, but this was dropped on the K4, which had a standard road-type fender. The CL175 ran until the K7 model of 1973, by which time the CL had also adopted the CB’s electric starter.
The final iteration of the CB/CL125/160 line was the CB200, which ran from 1973-1979. A further stretch of the bore to 55.5mm gave 198cc, and the front brake became a mechanically operated disc. A CL street scrambler was also offered, and all CB and CL200s had electric and kick starting. With little extra weight (under 300 pounds) and a claimed output of 20 horsepower, the CB200 was capable of over 80mph, and would cruise comfortably at 60-70mph.
In 2004, Brian King of North Hollywood, California, had a hankering for an antique motorcycle, but didn’t know what he wanted. “A friend of mine told me about a Japanese salvage shop about an hour away,” he recalls. “It was an old barn just full of bikes. I walked in there and said I was looking for a restoration project. The guy gave me a flashlight and said, ‘Go look around.’”
What King spotted was a sad-looking CB175. “I didn’t know anything about it, but it was all together, all there. It needed a lot of work,” he says, adding, “I got carried away when I brought it home and pulled it apart the first night.”
Why the CB175? “The ’69’s are an enigma,” King says. “It’s a bike that almost doesn’t exist. You can’t find anything about them. All I know that I’ve read is that they started production in June 1969. It was only a six-month run. They didn’t make that many of them. They’re a pretty rare bike.”
Eventually, King found a sales brochure for the K3, which gave him some clues as to how the bike should look. A first restoration was completed in 2004, though he wasn’t happy with the paint. “In 1969 they had candy colors, and I’d never painted candy before,” he says. Instead, King chose a plain orange finish. “I never liked it. It just didn’t look right. I ended up doing a repaint in 2009 to what it is today.”
Parts for the one-year-only K3 are hard to find, King says. “It took me a year and a half to find the gas tank. They made the CB175 for four years, but every year the parts are different. The front fender, the gas tank, the side covers, they’re all that one-year-only and they’re very hard to come by, although engine parts are about the same for all years.”
King found the engine ran well, so he decided not to strip it down. Unfortunately, while conducting a routine carb clean one year, he lost a washer. “I thought, ‘No big deal, I have plenty of washers.’ I put the bike back together again and started it, and realized the washer had fallen down the intake. It ruined the valves, ruined the piston, so it was time for a top-end rebuild.”
King has put about 8,000 miles on the K3 since that rebuild, and he’s clearly pleased with the results. “It just does everything like it’s supposed to,” he says. “It stops right, it handles right, it goes right, it never breaks down. It just goes and goes and never lets me down. The bike’s bulletproof.”
The engine thrives on revs, and King likes to fully exploit the powerband. “They only have 20 horsepower to begin with,” he says, “and the 20 horsepower is all at redline, so you have to rev it to get any power out of it. And they take it. The sound it makes is very intoxicating. At 10,000rpm it’s like a mini Grand Prix bike!”
King has seen very few K3s for sale, something he puts down to them being cannibalized for the CB160 racing class, especially the 5-speed transmission. “The ’69 was a transitional bike,” King says. “A lot of the parts on the bike are just bolt-on CB160.”
Another part of the bike King really likes are the brakes, which he says are particularly effective. “The 175 stops on a dime; it’s amazing how well it stops,” he says. “The CB200, which was the next model in this range, had a disc brake. But it was cable operated. Apparently it was so bad that people transplanted the drum brake from the CB175.”
How about the suspension and handling? “It works for me, but there’s not a whole lot of travel,” he says. Even so, of the bikes he’s owned, the CB175 is King’s favorite. “I’ve also had a 1969 CB350, a 1971 CL450, an S90 and a Super Cub,” he says. “But I love that little bike. It’s always been good to me. I just can’t see parting with it. It still draws crowds and it puts a smile on my face whenever I ride it, so it’s mine forever!” MC