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THE CHOPPER evolved from the race-influenced bobber into the apehangered chopper in an imprecise way. It wasn't as if the clock simply stopped on one style then started another. Styles simply
metamorphosed from one thing to another in the manner of a kaleidoscope and given the counter-culture, the summer of love
and the psychedelic times that the Sixties were reputed to be, it's an appropriate analogy. In 1960, there were relatively
few custom shops where dollars could be swapped for a sleek, chrome stallion. Grooming one yourself was the surest way to get a worthy
mount. In addition to several thousand dollars, you needed mechanical know-how and energy to break down and refine a 74 cubic inch Harley-Davidson engine that rolled from the factory with donut tires, a bulbous gas tank, heavy fenders and vanity size mirrors and an uninspiring
paint-job. We called them garbage wagons, but the 700 pound Harley stockers rolled like two-wheeled Cadillacs.
It was clear that a stock Harley was regarded only as the raw material from which a chopper would emerge. Behind the piggish profile was amazing power waiting to be freed with welding torches, wrenches and screwdrivers.
With the cycle stripped to the bare frame, the engine was torn down, bored out to 80 cubic inches, pumped up in horsepower.
A bicycle-sized 21 inch front wheel was fitted to extend front forks that raked back the cut-down frame, the effect multiplied by riser handlebars with silver dollar sized mirrors. The
fenders were thrown away or bobbed to the legal minimum. The cushy banana seat was thrown away and replaced with a lean saddle, the gas tank exchanged for a stinger with a 12-coat finish of lacquer. Finally, chrome pipes snorting, the beast stood ready to
buck with a chomp of metal gears. The finished bike was acknowledged as being 200 pounds lighter and therefore faster
because of both the improved power-to-weight ratio and the tuned engine. Freewheeling Frank, writing of
the same era in 1967, defined a chopper in much the same vein and also noted its origins as the particular choice of the 1%.' He wrote: 'A chopper means a Harley-Davidson motorcycle that has been stripped of extra accessories, including the fenders and tanks, which leaves
only the frame and engine. These are then replaced with small fenders and one tank - along with straight pipes as the
main changes. This leaves the motorcycle looking like a lean and furious monster. It's our creation, our breed
of horse. We love them.' Basically from 1948 to 1965, the Panhead was boss and its top end clatter a familiar and beloved sound. The big V-Twin motor looked at its best in a hardtail frame (i.e. Harley frames that pre-date the introduction of the Duo Glide). The looks of a rigid and a V-Twin started it all. The only rear suspension was the ten-pound rear tire pressure but the style was low, lean, and clean.
A righteous ride of the time consisted of the major components from the 74 cubic inch (1200cc) Harley-Davidson 'hog' and as
little else as possible. Chopped hogs were little more than the heavy Harley frame, forks and wheels, a 74 cubic inch V-Twin engine, small gas tank and tiny seat. Much more recently, Harley-Davidson registered the word HOG as an acronym for
the Harley Owners Group. They then set about litigating against all the chopper shops that had been using this particular slang in their shop names for decades. The irony in this is that the company
had regularly distanced itself from the '1%' and their choppers but frequently takes aspects of their style for its own, even admiring to the notoriety of the past in advertising copy and
equipping HOG members with back patches. The increasing numbers of British bikes being imported into the USA
meant that it was necessary to strip a Harley of its surplus parts as well as fitting dirt-track type components and tuning
the V-Twin. This meant that the Harley could be made to run on equal terms with the lighter British machines whether it was on
the track or from stop light to stop light. Harley's XL Sportsters were intended to compete with the British imports. However, by the mid-Sixties, the chopper had gone far beyond a stripped-down hog - it was rapidly becoming a work of art. The original idea of making modifications
to improve the motorcycle's function were overtaken by those to drastically change its form. Apehanger bars, bobbed fenders, small gas tanks and tiny seats were still de rigueur, but tall sissy bars, mini dual headlights, skinny front wheels, long mufflers
that sometimes extended up the side of the sissy bar and other such custom touches were becoming more and more common.
Chrome parts and custom painted gas tanks were also becoming increasingly popular. Sissy bars, so named because they stopped a pillion passenger from falling
off the rear of the machine, frequently reached to head height and were adorned with bayonets, swastikas or sculptures bar
designs as well as acting as a place to mount the tail light and license plate. In some places - and particularly in
Texas - they were referred to as 'bitch bars.' The Sixties, for right or wrong, were the era of LSD and free love,
of beautiful people and hippies, of Alan Ginsberg and Ken Kesey, of the Vietnam War - the US Marine Corps deployed in South
Vietnam in 1965 as the USA assumed a full combat role in South East Asia - and the protests against it. The late Sixties
saw America bitterly divided over the issues surrounding the Vietnam War. The belief that bikers were the defenders
of the counter-culture and the flower people's guardians had been exposed as a myth in the same year. A notable moment
had been when bikers interrupted an anti-war protest march from radical Berkeley toward the Army Depot in Oakland. The
truth of the situation was that it in the main bikers tended to be blue collar in upbringing and outlook while the radical
liberals were middle class. It was inevitable that the bikes of the Sixties would reflect the psychedelic
times in which they were constructed. Esoteric paint jobs and ever longer forks became the norm and a definite style
evolved. A radical chopper of the time featured a rigid frame, long forks - as often as not chromed springers - pullback
bars, a sissy bar and a multi-hued paint-job of swirls and shapes. To incorporate the extended forks the frame rake
needed to be altered. Alteration of the neck rake can have serious consequences for the handling characteristics
of a motorcycle and was the subject of enormous scrutiny. It is almost impossible to generalize about alterations to
the rake of a motorcycle front fork assembly but it is an important question for the builders and riders of choppers and those who regulate their construction and use. The two broad areas that need to be considered are handling and
structure. Considering the latter first, the structure question concerns whether the frame of the motorcycle is stiff
enough for the forces exerted by any front fork assembly. The longer forks exert different stresses on a frame.
Whether a frame is adequate depends on the forces applied to the structure, the size and shape of the frame, and the materials
from which it is assembled. All the forces applied to the forks and frame neck result from forces applied originally
at the front wheel, be they constant or varying. (Constant forces are those such as weight of the machine while varying
ones are those generated by braking and turning.) Lengthening forks without physically altering the neck rake of the
frame still alters the rake because of the additional length in the forks. It also changes the weight distribution of
the whole motorcycle to the wheels - the longer the forks the less weight is supported by the front wheel, i.e. the constant
load is reduced, although the center of gravity stays almost constant in relation to the rear wheel. Altering the neck
rake of the motorcycle frame has similar effects, and of course, the steering neck loads vary with wheelbase because of the
torque applied. The load on the front wheel decreases as the load on the frame neck increases due to the lever increasing
faster than the weight decreases as wheelbase is lengthened. When the motorcycle is moving the forces applied to the
front wheel increase rapidly when the wheel rolls over bumps. The forces applied vary both in terms of amount of force
applied and also the direction from which it is applied, including cornering and braking forces. The rule of thumb is
that cornering forces when the machine is banked over to 45 degrees will increase the weight of the bike and rider by around
40 percent. The neck torque will also be raised by 40 percent independent of neck rake and extension. Braking
loads are more dependent on wheelbase, in turn dependent on both neck rake and extension.
Braking with the rear wheel only some distance behind the
center of gravity gives rise to a torque action that results in an increased force on the front wheel and as the weight of
the whole does not increase there is less weight on the rear wheel. If the brakes are applied harder, the weight on
the front wheel increases further and the weight on the rear decreases correspondingly. The next stage is that any further
increase in torque through yet harder braking will cause the wheel to skid. When only one wheel is braked the torque
caused will be less than when both are braked so the weight shift will be correspondingly less as will braking force.
The actual percentages are affected by wheelbase. For example, with an 85 inch wheelbase almost 60 percent of the braking
force of a two-wheeled system can be achieved with only the rear brake while on a machine with a stock wheelbase the percentage
is considerably smaller. Structurally, the percentage of torque increase on the steering neck is most important and
in rear break only machines the percentage increase is dependent on wheelbase but when both brakes are used it is almost 60
percent constantly. These figures mean that particularly long wheelbase choppers with front and rear brakes needed frame necks up to 90 percent stronger than stock, and rear brake only bikes (which were,
and are, not legal everywhere) needed frame necks up to 70 percent stronger than stock. Loads that
affect the steering neck must be transmitted to it by the forks and have a force-versus-compression characteristic inbuilt.
In the case of the springer and girder forks there is some kind of damping through either friction or viscous damping.
Even the friction in the swiveling joints has some damping effect but the front end needs to be constructed so that the springs are not bottomed out when the machine is static. The dynamic loading of
the forks varies depending on the direction from which the load is applied, something affected by rake, the size of bump and
the speed at which it is hit. Handling at various speeds is influenced by length of wheelbase as well
as rake and trail. Rake is as described above and trail is the distance from an imaginary line down from the center
of the axle to where it intersects with an imaginary line down from the steering neck at the angle of the neck. A bike
with a short wheelbase, short forks, small rake angle and correspondingly small trail will handle well at low speeds and be
maneuverable, which makes them ideal, for example, for cross-country, off-road bikes, while a longer wheelbase, bigger rake
and therefore larger trail will be more stable at higher speeds. Drag bikes are an example of this extreme; road bikes,
race bikes and similar fit somewhere in between. In choppers the style is more important than the function, although the machine has to be ridable. As a result many choppers are stable and comfortable at freeway speeds but less stable and maneuverable at low speeds. Adjusting the angle of
the steering neck is one way to account for all these factors and to accommodate longer forks. In the late Sixties,
a frame modification known as a goose-neck became popular. It was so called because the finished frame resembled a goose's
neck. The frame top tube to the headstock was extended forward and the down-tube was extended up and forward before
the steering neck was refitted. This had the effect of lengthening the wheelbase and adjusting the neck to suit extended
or after-market forks. Springer forks were popular initially for choppers and as after-market forks became commonly manufactured the problems with excessive trail could be eliminated through use
of different length of rockers, i.e. the plates that connect both pairs of legs of the forks and carry the front axle.
The conclusion that chopper builders soon came to were that frame necks required considerable strengthening for all but very small increases in wheelbase, rake
and trail alterations could be mastered, and that as braking forces are not concentrated in the front wheel in long wheelbase
bikes they were not as unmanageable or unsafe as some overzealous traffic cops might claim. Numerous
custom parts and chopper parts companies started in business in the late Sixties including two Minnesota companies: Smith Brothers and Fetrow of Minneapolis,
and Drag Specialties of Eden Prairie. In 1969, Chicago Cycle Specialties of Chicago, were advertising tubular gas tanks, oil tanks, fork tube extensions, custom handlebars, seats, fenders and custom up-swept exhausts. For 'show or go' there were
pipes listed for 1947 and earlier OHV, 1948 and later OHV, 1958 OHV suspension frames (Knuckleheads, Panheads, and Duo Glides) and XLCH Sportsters. Apart from those for the Duo Glide, they retailed at $49 and extended way above the rider's head. Possibly
the biggest boost choppers have ever had came in the last year of the decade. Columbia Pictures released Easy Rider. This film
more than anything else propelled the image of the chopper and the biker beyond the boundaries of California and its outlaw clubs and San Francisco's Haight-Ashbury circles. However, it wasn't the first of the biker movies. Kramer's The Wild One had that distinction and there had been others through the Sixties. Easy Rider was not a big budget movie;
it had cost only $375,000 to make and would go on to eventually gross more than $20 million for its distributors. It
didn't have a complex plot, simply following Wyatt and Billy on their choppers and on the road, but it captured the mood, moment and the movement of the time perfectly. It was described - 'It was
like drifting off into another world, a world which we desperately wished to experience for ourselves. In that single
ninety-four minute budget movie, Dennis Hopper managed to encapsulate brilliantly the very spirit of freedom that we had all
felt, at one time or another, out there on the road. He represented on screen a ceremonial vindication of what we'd
known all along but were unable to articulate.' The film portrayed choppers completely typical of the time. Both of the characters ride Panhead choppers although they differ in style. The Captain America bike is Fonda's ride. It is a wishbone rigid-framed bike with
an overstock telescopic front end. Apehanger bars are mounted on risers. There is no front brake or fender. A Mustang tank, dual seat and
tall sissy bar are fitted, and the chopper is finished with a Stars-and-Stripes flag paint-job. Hopper's ride is a flamed chop. It too features a wishbone
frame and Mustang tank but the forks are not as long or as raked and have T-bars bolted to the top yoke. The bike has
a small, English-style front fender and the stock drum brake. These two choppers are the machines that launched a style for choppers that irrevocably link choppers with long forks together. Fashion being what it is, while both bikes would still be welcomed at any custom bike event, Fonda's looks like a late Sixties/early Seventies chopper while Hopper's slightly more restrained machine hasn't really ever gone out of style with the possible exception of the style
of handlebars. So famous have these two motorcycles become that Easyriders magazine
built replicas for display and promotional purposes - the replica Captain America bike is included throughout. As a
direct result of that movie, rigid frames and high bars are as much a part of motorcycling for many as highways and Harleys.
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