Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/126293
Te,t: loftda CIX ~g~7cc-6 p,ototyp. DQ IWATA,JAPAN, AUG. 5, 1977 A group of journalists meets with Yamaha Motor Co. engineers to discuss the XS 11, a motorcycle the' writers had all ridden for the first time that morning. Several complain of an annoying drive train lurch whenever the throttle is opened or closed at slow speeds. Mr. S. Tanaka , director of four -stroke motorcycle engineering, shrugs his shoulders. "W hen we tested our prototypes," he explains , "t here was no problem. But when we started the production line , suddenly this condition appeared . We are working on the solution." The exchange ~llustrates a known fact : production machines rarely work as well as hand-built prototypes. A skilled machinist can make a more precise transmission gear out of solid metal than can an automated gearcutting machine fed forged blanks. However, in the time the machinist makes one gear, the machine produces 100 . Productivity demands greater tolerances, . ROSAMOND , CA , OCT. 24, 1977 Before sunrise, two journalists and two 6 photographers from America's largest monthly motorcycle magazine arrive at Willow Springs Racew ay . They have come to this desolate desert location to test the prototype Honda CBX , months before the giant Japanese manufactu rer will even admit to other publications that such a machine exists. The motorcycle is dominated by its massive engine. Six cylinders. 1047cc. Double , dual-piece overhead camshafts. Twenty-four valves . Six 28mm constant velocity carburetors, with accelerator pump. The CBX is like no other street motorcycle ever seen. It 's not just the basic type and configuration that sets the bike apart. It's also the obvious clues that this motorcycle has been hand made, a pre-production test model. The clutch cable adjuster lock nut, for example , is shaped and lightened, a part straight off a Honda works road racer. The engine castings are all rough from the sand which formed them . The aluminum fork cap nuts bear machining marks. The gas tank has imperfect contours, the product of an unfinished press mold. A former editor of Cycle News West,John Ulrich left hispost in August 1977 to become an associate editor of America's largest monthly motorcycle magazine. In December 1977, Ulrich was discharged in a storm of controversy related to the magazine's "exclusive, first test " of the prototype Honda . CBX. This is the story of that test - and of the most exciting street motorcycle ever built. It's likely that the same is true of the engine internals. Every part painstakingly fitted to every other part. And it's likely that this CBX will - run and handle and work like no CBX ever to follow . If that fact worries the editor who has negotiated this "exclusive test, " he doesn't show it. Instead, he is ecstatic, overflowing with graciousness towards the Japanese executives and mechanics who ha ve accompanied the CBX from Japan. The editor ca lls his arrangement of this test " t h e highpoint of my IO-year career with the magazine. " It takes months for a magazine story to travel from typewriter to newsstands. In order to insure that his magazine would be the first to feature the CBX . the editor had to test the machine long before the bike was to be introduced to other members of the press . And since weekly publications like Cycle News -h a ve much shorter lead times , absolute secrecy had to be maintained. But Honda could not supply a production model CBX for testing that early. The only alternative - and the alternative agreed upon by both Honda and the' magazine - was to test a prototype. The implications were obvious , and no one dared mention them . There was another problem. Honda needed the only prototype US-market CBX to film 'a promotional movie to be used to introduce 1978 models to Honda dealers. As part of the deal , the editor would ride the CBX in the Honda movie , filmed at Willow Springs. Movie cameras whir as scene after scene is staged and photographed. Between takes, the journalists ride the CBX - a street bike - around the road racing circuit. " he bike sounds like a POTSChe, emitting a smooth, six-cylinder snarl with each blip of the throttle. In spite of the chill fall weather. the Honda starts easily and settles into an idle at less than 500 rpm . A rider climbs aboard. and gazes down at the cylinders sticking out beyond each side of the wide gas tank. Now warm, the six idles , at 1000 rpm . From 1000 rpm the CBX will pull away from a stop. The engine is torquey. and nowhere in the rpm range - from idle to the 9500 rpm redline - is there significant vibration. The CBX isn 't as glass-smooth as the watercooled GLlOOO Gold Wing, but it's smoother overall than any other motorcycle . . At 6500 rpm the CBX delivers a noticeable horsepower "kick ." but the engine makes power over such a broad range that the bike seems slower than it actually is. Even above 6500, the motorcycle seems to lack the punch of a Yamaha XSII or a Suzuki GSlOOO. More than smooth, the CBX is taut. Driveline snatch is nonexistent. The rider can slow the CBX down to 1500 rpm in fifth gear , slam open the throttle . and smoothly. quietly , steadily accelerate up to as fast as he