Cycle News - Archive Issues - 1980's

Nigel Gale and his teammates rode a Harley-Davidson FX in the WERA 24-HourWestat Willow Springs last June, finished 11th overall. The bike performed flawlessly with no engine problems. 66 junction with the primary oil bath. Since the clutch bousing is made of aluminum and immersed in the primary oil, the new clutch also runs cooler than the. old dry clutch. But the big news in the clutch department is that the cl utch plates are actuated by a large diaphragm spring, rather than the bauery of coil springs used previously. Not only is the diaphragm strong, but it's easier to operate and has a much lower lever pressure. Characteristic of the diaphragm spring is that the greatest clutch lever eHort occurs in the middle of the lever stroke - about 19 pounds of holding eHort. Surprisingly, holding the lever in all the way (like silting at a stop light) requires only nine pounds of holding effon. Harley's new clutch is smooth, strong and easy 10 operate; a definite improvement over the old models. In the FXRS, this new clutch drives Harley's latest five-speed transmission. Shifting is much improved over the old four-speed' box, though still substandard when compared to the latest oHerings from the Orient. Neutral is easy 'to locate - thanks largel y to the minimal drag imparted by the new clutch. Though the layout and ratios are the same as used on recent five-speea boxes, the 1985 Low Glide's transmission is encased in an entirely new housing, required due to the extra width of the belt-drive. Belt-drive. Wby botber with a beltdrive in the first place? According to Harley-Davidson, this system aHords the advantages of low maintenance, light weight. no chain-lube me s, and greater efficiency than a shaft drive. Additionally, the negative handling aspects inherent in shaft drive systems are sidestepped. But probably most important: the belt system was easy to adapt to Harley's existing designs. The advantages of the belt-drive could be realized witbout expensive engineering and retooling. . Harley began experimenting with the belt-drive system as early as 1975, inan eHort to modernize their chaindrive motorcycles. The belt concept represented a considerable gamble on behalf of Harley-Davidson. Reliability was obviously a question - and at that time, Harley-Davidson had more than their'share of reliability trouble. Public acceptance was also a question mark; how would people take to . the notion of their motorcycle being driven by a .rubber band with teeth? To hedge their befs, the belt was introduced on the Sturgis; a model that was nei ther advertised nor pro- Evolution Harley-Davidson engine in our test bike was oil tight; but the case for the chain primary drive leaked oil on the drive belt, which threw it all around the bike. Belt final drive typically lasts 50,000 miles, but gear ratios can't be easily changed. moted by the factory for more than a year after its introduction. If the peltdrive proved, for any rea on, 10 be a failure, the Sturgisand its controversial drive sy tem could vanish quietly as a curious footnote in Harley's history. The past four years have proven those fears to be unfounded. Typically, the belt-drive Harleys take an initial adjustment at 800 miles, followed by IO,OOOmilecheck-ups. Total service life is commonly in excess of 50.000 miles. The drawbacks' Replacing the drive belt involves removal of the swingarm - not an easy roadside fix. For short-range emergenci s, a roadside repair kit is available that's good [or about 200 miles; hopefully. farenough to find a dealer for a new belt. Drive belts are also especially susceptable to damage from rocks and road debris. To minimize chances. of such damage, 1985 Harleys are fi lted wi th a rock shield atthe'junction of the belt and the rear sprocket. . As far as the owner is concerned, the only, worry for the drive belt has to do with adjustment. Since the belt engages over a width of I Y" inches, rear wheel alignment is critical. If the rear wheel is cocked to one side, a narrow strip at the edge of the belt ends up carrying the drive loads - not good for belt life. Another concern is that gear ratio can't be changed by wapping sprockets. Harley doesn't currently offer the belt sprockets in any sizes other than those provided as stock. No big deal... for that malter, there's no easy way to change the drive rauos on a shaft-drive bike either. The entire powertrain of the FXRS Low Glide (engine, transmission, swingann and rear wheel) is isolated from the rest of the frame by a, system o[ rubber bushings. Pioneered on the touring FLT in 1979, this system effectively absorbs engine vibration and isolates the rider [rom the beating and thrashing of the 80 cubicinch V-twin powerplant. Why the enure drive train and not just the engine? If only the engine were suspended in the mounts. the high frequency engine vibration would translate into a constant tugging on the drive chain (or belt). Such tugging, coupled with the tension of driving the motorcycle, would quickly pulverizeachain or belt. With the entire drive system isolated, all the components from the rear wheel forward can assume the vibration frequency of the engine without any additional stress on the belt or chain. And the rider can go about his business undislUrbed by the vibes that made Milwaukee famous. Supporting this rubber-isolated drive train is a new cO'mputer-ilerived frame, made of welded tubular steel. Gone is the welded lug frame from the days of old - and all the extra weight and flexing inherent in that design. Harley's new frames are strong, light, and every bit as modern as those produced on other continent . This new high-performance frame was first incorporated on the FXRS, introduced as a 1982 model. Harley wanted it made clear that this frame and rubber isolation system represented a departure from their traditional designs - and welit so far as to call the FXRS the "Super Glide II." To emphasize' the handling powers of this new 'Glide, the inaugural FXRS was fiued with a sporting (by Harley's standards) suspension. Cornering clearance was surprisingly" good, and it took dedicated canyoncommando tactics to drag any biLS of the undercarriage. But the bike didn't sell. Feedback from the dealer level indicated tbat the FXRS felt "taller" than other biginch Harleys, -and needed a lower profile to be successful. Harley agreed, and responded by changing the name to "Low Glide," and dropping the seat height lOa low-f1ying26.8 inches. Predictably, this was achieved by chopping the suspension: shortening the front forks by two inches, and trimming the rear shock travel by 0.7 inche . For the new FXRS, handling remained about the same, but corneringclearance was impaired due to the lowered su pension. Even moderate cornering gymnastics resulted in .the decisive scrape of metal on asphalt, [ollowed by a shower of sparks. For 1985, a compromise has been reached. The name "Low Glide" is still with us, but this year the same bike can be ordered with the suspension introduced in 1982. The "OptionaI Performa nce-S us pens ion Package" includes the suspension bits from the previous FXRS, as well as an extra disc brake on the front wheel '(dual dis s are "in" for performance bikes, you know). Of course the front brake master cylinder has revised hydraulic ratios to suit the extra disc. The perforrnance.package adds about 10 pounds to the overall weight of the FXRS Low Glide -due primarily to the additional brake disc and caliper. ••••• There's no mistaking the overall intent of the Harley-Davidson FXRS Low Glide. The pulled-back handlebars. soft, stepped seat and highway pegs define this motorcycle as a mem bel' of the Street Cruiser fraternity. Styling is pure American Custom, because... well, dammit, that is an American Custom motorcycle. Our test FXRS came equipped with the Optional Performance-Suspension Package. which did nothing to detract from the classic lines of this machine. In spite of the taller suspension, our test bike wore the name "Low Glide" well. The seat height is a mere 27.5 inches - which just a few years ago would have made this the lowest flying street bike on the market. If a lower saddle is more salable, it's debatable as to whether it's more desirable: This is especially true when the

• Cover