Sheep in Wolf’s Clothing: 1979-1982 Moto Guzzi Le Mans CX100

The original Moto Guzzi 850 Le Mans of 1976 was not much more (or less) than an endurance racer with turn signals. The 844cc engine featured filterless, bell-mouth 36mm Dell’Orto carburetors, a 10.2:1 compression ratio, and a sports exhaust for a claimed 81 horsepower. The Le Mans made little concession to creature comforts, but provided sparkling performance and handling for the sporting rider. It was a critical (and commercial) success in both Europe and North America.

The specification stayed largely the same until 1979, when the story got more complicated. That year, European markets got a MkII 850 Le Mans with similar specification but revised bodywork. The U.S. version, however, got the new 1000SP’s quieter, cleaner and somewhat detuned 949cc engine. Several sources have suggested this was a response to ever tightening noise and emission regulations, but Greg Field’s book Moto Guzzi Big Twins quotes Mike Berliner of U.S. importer Berliner Corporation saying it was simply a response to American dealers’ belief that bigger was better. Thus was born the U.S. market CX100, which was essentially a touring 1000SP Strada with MkII Le Mans bodywork.

The 949cc 90-degree air-cooled, overhead valve, wet sump, V-twin engine was fitted into the same Tonti dual cradle frame as before. Two Dell’Orto 30mm carbs (now with proper air filters) fed the iron-lined alloy cylinders running a 9.2:1 compression ratio, while a 280-watt alternator at the front of the engine ran the electrics. Power was transferred through the automotive-style twin-disc dry clutch to a 5-speed gearbox with shaft final drive, the final drive casing forming the right side swingarm tube. Three-position preload adjustable shock absorbers located the swingarm to the frame.

Both front and rear wheels were cast alloy, the front attached by Guzzi-designed, hydraulically-damped spring forks, and both wheels were 2.15-inch (WM3) section by 18-inch diameter. Tires were 110 section rear and 100 front.

The CX100 carried over Guzzi’s linked braking system: Pushing down the right-mounted foot pedal activated both the single Brembo rear disc caliper and one of the two front calipers at a ratio of 70 percent front, 30 percent rear; squeezing the hand lever then gripped the other front disc. Though many riders were suspicious, Rider concluded the setup worked well in their tests: “…the integrated system allows safe cornering on slick surfaces or for non-skid stopping beyond that of conventional brakes.” Stopping was “shorter and more stable,” they said.

The U.S.-spec Le Mans CX100 (the U.S. press referred to it as both the CX100 and simply the Le Mans), made approximately 80 horsepower, claimed Rider magazine, though in other sources it was quoted in the 70-80 horsepower range. And while 17 pounds heavier than the 850, performance was still quite adequate, with 13.5 seconds to complete the standing quarter at 98.5mph versus 13.1 @ 103mph for the 850.

Once Rider’s testers got used to the low-rev power pulses from the big twin, they said they enjoyed “how the Le Mans lifts itself through the rpm range so easily, smoothly and effortlessly.” They also liked its handling, praising how it “sweeps, instantly dodges and hangs into corners with utter safety, stability, and a very eerie self-steering stabilizing effect.” Cycle found the Le Mans CX100 “extremely stable in every kind of cornering except going flat out in bumpy sweepers,” which was the only time they found the adjustable steering damper “can provide a useful steadying influence … most riders who throw a leg over the Moto Guzzi will use up their riding skills long before the bike’s abilities are exceeded.”

However, the riding position required a long reach to the bars from the firm, narrow seat: “In the city, no one is likely to feel too comfortable on the Le Mans,” Cycle commented. However, they liked the CX100’s wind-tunnel developed fairing better than the 1000SP’s (“[the] wind just brushes your shoulder”) while Rider liked the instrument panel, calling it “a true pilot station with a full spread of gauges, dials and even a quartz clock.”

Some issues did arise: Checking the screw-adjustable tappets every 1,800 miles required removing the side panels; changing the oil filter meant removing 14 bolts to drop the oil pan to gain access; and the sealed beam headlight was, Cycle said, “a joke.”

Summing up, said the same magazine, “… if you appreciate craftsmanship, aesthetics and function, you should be drawn as if by magnets to the Moto Guzzi Le Mans. It is one of a special few.” And it still is. MC

Sport-touring rivals to Guzzi’s CX100

1980-1984 Hesketh V1000
Claimed Power: 82hp@6,800rpm
Top Speed:130mph
Engine: 992cc air-cooled DOHC V-twin
Weight: 551lb (wet)
Fuel Capacity/MPG: 20-40mpg
Price Then/Now: $10,500 (1983)/$10,000-$20,000

Want to make a small fortune in low-volume motorcycle production? Then start with a large one. Just ask the Right Honorable Lord Thomas Alexander Fermor-Hesketh. After dabbling in the even-spendier world of Formula 1, the Third Baron Hesketh decided he would revive the British motorcycle industry. The V1000 was the result. Sadly, it never became the sum of its parts. Built around a Weslake-based V-twin with Cosworth-designed DOHC 4-valve cylinder heads, the Hesketh should have been a British Ducati, but the power delivery was rev-happy, lacked V-twin grunt and didn’t suit Hesketh’s grand touring ambitions. The gear-driven 5-speed transmission was also clunky, and the Rob North-inspired Reynolds 531 steel tube frame created a high center of gravity while limiting ground clearance.

The kicker was the mechanically harsh engine was unable to meet European and U.S. noise regulations, and fuel consumption could drop into the 20s and even teens! Top quality components from VDO, Brembo, Marzocchi, Denso, Astralite and Dell’Orto couldn’t save a flawed design. Nor could gleaming paintwork, radiant nickel plate, lustrous alloy casings and meticulous fit and finish. Hesketh pulled the plug — twice — after fewer than 200 bikes were built. Ex-Hesketh employee Mick Broom continued limited production until 2010 and the brand has recently been reborn, but that’s another story.

1977-1984 BMW R100RS
Claimed Power: 70hp @7,250rpm
Top Speed: 108mph
Engine: 980cc air-cooled OHV horizontally-opposed twin
Weight: 535lb (wet)
Fuel Capacity/MPG: 42-50mpg
Price Then/Now: $7,275 (1981)/$3,500-$7,500

The BMW R100RS’ unique selling point was its all-enveloping fairing, developed by Hans Muth (who designed the Suzuki Katana) in the Pininfarina wind tunnel. The fairing improved fuel consumption over the naked R100/7 by 4mpg at 62mph, and — almost as important — reduced lift on the front and rear wheels by 20-25 percent for added stability at high speeds.

The RS arrived in 1977 with wire wheels, dual front discs and a drum rear brake. By 1978 it had gained BMW’s “snowflake” alloy wheels and a rear disc brake. Improvements over its life included gearshift enhancement, a new crankshaft, lighter clutch and flywheel, an oil cooler and Nikasil plated cylinders. Although the K100 was in development and ready to replace it, the air-cooled Boxer engine continued in the GS series until the mid-Nineties.

Some testers found the riding position — quite forward with narrow handlebars — uncomfortably heavy on the wrists, absent the balancing airflow of a naked bike. The brakes were criticized for being too stiff and they also noted head-level turbulence from the windshield.

The suspension was also criticized as being too soft for good handling, though the ride was “simply first rate,” said Cycle. The RS was perfect for “those who enjoy its composed nature, its swiftness over long distances, the crispness of its controls, and its full-fairing shelter without cross-wind susceptibility.”