This text was initially printed within the August-September 1998 problem of Cycle World’s Large Twin journal.
Each mannequin Harley ever launched, besides the primary, upset the followers of the earlier mannequin. The 61 E Knucklehead would be the most worshiped bike The Motor Firm ever constructed, however the legions of followers impressed by the 1948-65 Panheads are elated that Harley canned the Knuck.
The primary Panhead—or mannequin FL, accessible in each 61- and 74-cubic-inch fashions—arrived in sellers’ showrooms in 1948, simply in time to be a significant a part of the postwar bike increase. A era of younger servicemen had grown up on the battlefield, a few of them having ridden Harley’s WLA 45-inch army mannequin in fight. Although gradual as molasses, the massive, low-powered twin captured the imagination of most of the troopers who rode it, whereas stirring pangs of jealousy in most of the foot-slogging infantry.
When the conflict was lastly over, the GIs got here again to a quickly enhancing nationwide freeway system. The brand new riders had the earnings to pursue touring and leisure on two wheels, and the will to do it on Harley-Davidsons.
With its cast-iron heads, which offered meager heat-dissipation capabilities, the Knuckle discovered it robust to outlive on the newer, straighter highways, roads that inspired quicker speeds and for much longer journeys: You would simply experience from one finish of the nation to the opposite, needing to cease just for gas and meals.
That first FL in 1948 was based mostly on the dependable transmission and bottom-end of the EL, however the “Knuckleheads” have been changed with massively finned cast-aluminum heads that might radiate and dissipate warmth far more effectively. The brand new engine additionally was outfitted with an uprated oil pump to enhance cooling and lubrication. And, in hopes of ending cylinder-head oil leaks all the time, Harley’s designers enclosed the rockers and valve springs underneath one large, pie-pan-shaped cowl—therefore, the “Panhead” nickname.
Modifications introduced challenges. Because the engine warmed, the brand new alloy cylinder heads expanded and grew far more than the previous cast-iron heads; and due to the Large Twin’s practically four-inch stroke, the quantity of growth was appreciable. As the top grew away from the cylinder base, elevated valve lash would have resulted, have been it not for the incorporation of hydraulic tappets that mechanically maintained valve clearances. Although these tappets initially have been problematic till 1953—when their location was modified from atop the pushrods, the place they have been starved of oil, to the underside, the place they bought ample lubrication—they meant that valve adjustment was without end crossed off the H-D rider’s checklist of frequent upkeep chores. Only one yr later, in 1949, a hydraulically damped telescopic fork changed the venerable springer entrance finish, and the FL was aptly given the Hydra-Glide identify. The mile-eating qualities of the Panhead grew to become apparent when Harley-Davidson began its Mileage Membership in 1951; inside simply 4 years, 73 riders had earned their 100,000-mile pins, many on Panheads. The Panhead grew much more comfy but when the 1958 Duo Glide launched rear suspension. That yr additionally was the final through which hand-shift/foot-clutch was accessible, and even then, it solely might be had as an choice.
Hydraulic drum brakes additionally arrived in 1958, and for good motive: At round 700 kilos, Panheads weighed twice as a lot because the imported British competitors whereas producing comparable peak energy. They’d by no means win any races, however the H-D Twins had endurance, and sufficient torque to eat up mountain passes in excessive gear. The plush new fork, mixed with a long-travel sprung seat and huge, comfy footboards—to not point out the aforementioned change to a hand-operated clutch and foot-operated gearchange—mixed to make a roadburner that was troublesome to beat over the lengthy haul. And with the 1965 Electra-Glide got here 12-volt electrics and the posh of pushbutton beginning, rendering the kickstarter out of date—though it continued as an choice for an additional 20 years.
All through the Panhead’s 18-year existence, oil pumps and bearing sizes have been virtually frequently uprated, as a result of serpentine oil passageways of the FL and the ever-increasing energy calls for being positioned on Large Twins. By 1960, claimed output was as much as 60 horsepower. These upgrades, along with the adjustments essential to accommodate electrical beginning, meant that the Panhead used six totally different crankcases over its lifespan.
However the yr through which electrical beginning first appeared, 1965, additionally was the Panhead’s swan track. The leaner, more-powerful Shovelhead would exchange it in 1966.
Within the Sixties, the prepared availability of used Panheads was a boon for the chopper motion. Certainly, the Pan’s best fame would come as a chopper, because the “Captain America” bike within the film Straightforward Rider.
Some Panhead followers, nonetheless, favor to guage these bikes strictly on their deserves. The lifespan of the Panhead was one among fixed enchancment; however for a lot of fanatics, the 1949-57 rigid-rear Panheads, with their traditional mixture of operate and pure American model, stay inconceivable to beat.
So, whereas the period of the Pan could also be lengthy gone, the bike itself has by no means been forgotten.