Without question, the most difficult part of writing this chapter preview was fighting good old-fashioned bias. Like everyone, I have my favorites but no matter how cleverly written, history cannot be accurately served by highlighting the passions of just one person. For example, when recalling the models available to the post-war 1950’s buyer it’s all too easy for this compiler to carry on about the Vincent twin or Germany’s mechanically advanced BMW – two legendary brands largely overshadowed in the US. A natural question then; what overshadowed them?
Repeating what’s written in Part One, motivation for this essay is two-fold. First to promote my Superbikes book (long a work in progress) and second, to recognize motorcycling’s speediest forefathers. Following the established theme, these machines offered the ultimate specification per era, but here’s a chance to contribute if you believe something important is missing. Write firstname.lastname@example.org with your info.
Into the early 1950s and celebrating post World War II bliss with the rest of the world, both auto and motorcycle production was slowed stateside by an unpopular conflict in Korea. Happily for riders everywhere, those surviving builders were again moving ahead in Europe and neighboring Britain. New, advanced tooling streamlined accuracy and durability, allowing makers to annually increase power. Using concepts studied in Germany, the new taxpayer funded interstate system dramatically altered (influenced?) what US cars and motorcycles would become. Offering size, comfort and speed to cover thousands of open road miles, simple demographics played a part in shaping big-inch American cruisers.
(Dropping the ball by omitting BMW’s R66 sports (shaded) in part one, we won’t repeat that mistake with the limited edition R68 Sport from 1952-1954. Bimmer’s first post-war sports model, the R68 was based on the touring R67/2 (left-side profile) and tuned to compete with Britain’s faster twins. Shaft and plunger detail: Pipeburn. Bigger valves, cam, compression, carb size, advance, a special exhaust and a stronger crankshaft resulted in a factory rating of 35-hp. Note trim fenders and low bar. Promoted as ‘The 100-mph Motorcycle’ BMW’s R68 only trailed the Vincent for cross-country speed)
No other production motorcycle lived at the top longer than Vincent’s 1000cc Black Shadow twin. And it’s not close. Drawn and making its public debut in pre-war Series A form, Phillip Vincent and engineer Phil Irving emerged at the other end of the conflict to begin a two-decade run of undisputed global speed dominance. Any coverage recalling the historic high points of performance motorbikes would be incomplete without Vincent, but there’s little left to say that hasn’t been said. At its center lives what many consider the most beautiful internal combustion engine ever, and I won’t argue it. Defining the term superbike, nothing before or since equals the Vincent’s timeless mechanical presence.
Thanks to the very generous (and trusting!) Denny Delzer, in 2004 I was awarded a 1948 Series B Rapide (pictured in the tall grass by Denny) to use for transportation at the Vincent International rally in Canada. Before then, I loved looking at the examples on auction at Mecum and Bonhams like nearly everyone else, but actually riding one at speed deepened that perspective. Mastering the start was easy enough, and blasting along the Canadian back roads chasing Denny caused me to wonder just how different the Shadow’s tuned, 998cc 50-degree twin would be. My lasting impression is the Vincent’s completeness – its smooth, thrusty power, strong brakes and handling on par with the decades newer R75. There’s no doubt Lightning bits would add drama to the experience, but I’m sure the Shadow’s 7.3 comp pistons, big 1-1/8″ Amal carbs and polished/lightweight internals is a reliable limit. Owned and prepped by Arizona’s TJ Jackson, this 1954 C features Girdraulic forks. I’ve heard the later bikes are better, at least, mechanically. Cemented into both historical and social timelines The Vincent remains a young blood. Eager to run.
Stateside, no late 50s/early 60s motorcycle was hotter than Harley Davidson’s XL Sportster. In my younger days I concluded overblown nationalism the cause for loving what I considered a flawed brand, and there’s no one to blame but my father – a former owner. Getting my Guzzi V7 twin six-months after dad bought his, my thinking was heavily influenced hearing him talk about all of the things Guzzi fixed. That is, compared to the worn Knucklehead ‘74’ he dragged all the way from Iowa to Arizona. To his credit, pop was honest and later explained watching the Sportster (or perhaps the rowdy side-valve KR racer) feasting on Britain’s fastest throughout the 1960s Midwest dirt track scene. Back then, nothing touched the Sportster for street cred, and it aged well. Essentially a KH roadster fit with a new, 4-cam OHV engine, the 883cc twin is a dry-sump unit with chain primary and four-speeds. Because of concerns using aluminum, both cylinders and heads were made from iron. Very soon, Harley was offering the tuned XLCH and as years scaled into decades, Milwaukee’s sports twin was revised into a staple of American life.
(In black and white, 1957 XL Sportster from Bonhams. 883cc, 4-cam ‘Ironhead’ changed little through the years. 1971’s 900 looked very much the same)
As with Harley, Ariel’s Square Four Mk II makes the early superbikes list based on displacement, but there’s more to this 1000cc multi than the rarity of its size. Designed as a 500cc in the 1920s by Edward Turner the Four was updated four times in an effort to bump performance and cure the big roadster’s habitual overheating. For 1953/4 in final M.K. II form, the all-alloy four was revised with a larger cylinderhead casting with four-pipe exhaust manifolds. In a production sense the engine was unique with its twin crankshafts, but followed traditional practice with chain primary. Long a favorite for sidecar use, the lighter, leaner Mark II emerged as a true 50s superbike, even with mild 6.0 comp pistons and single SU carburetor. In his book “A-Z Guide To British Motorcycles” author Cyril Ayton told the urban legend of racer-turned journo Vic Willoughly’s dash to Scotland on a Mark II test bike in 1955. “140-miles in two hours, using the A1,” Ayton reported. “And it should be noted, the Ariel’s overheating issues were not completely solved.”
Feature – Harley Davidson FL
As it is with the Vincent, generating an original thought on the world’s most popular motorcycle is no small task. But circumstance smiles this time, considering my first exposure to motorcycling was dad’s 1947 Harley FL Knucklehead. Being very young, my actual memories are more of a dream sequence now, but I do recall pop placing me in front of him on the buddy seat, where I’d reach for the handlebar clamps to hold on. Leaning to grab my first pair of clip-ons as dad rode the narrow lanes of northwest Iowa shaped my perception of how it would someday be…even if I couldn’t stop rubbing my itching, vibration riddled little hands afterwards.
Just having the one photo of dad’s bike plus needing to look at Harley’s modernized 1950’s Panhead, these quaint photos from South Florida’s Blue Gosse frame the scene. Somehow more appealing wearing its well earned oxidation and grease, this is how a proper Seventy-Four is supposed to look. Full honk. According to the National Motorcycle Museum in Anamosa Iowa, Harley’s full-figured form blossomed under the pen of Brooks Stevens, credited for the Hydra-Glide of 1949.
Harley FL 1200 specs:
Engine: Air-cooled, OHV 45-degree v-twin
Displacement: 74-C.I. (1208cc)
Compression Ratio: 6: 1
Intake: 1.30” Schebler
Primary: Duplex Chain
Top speed: 105-mph
Nestled in a double-cradle tube frame with rigid rear, the 1208cc, OHV Panhead took over for dad’s last edition Knuckle in 1948, with hydraulic forks replacing the girder one year later. Foot shifting became an option in 1952, and in five years the 74-CI Harley became the Duo-Glide with the addition of rear shocks. Engine improvements included alloy cylinder heads with aluminum/bronze seats, valve rotators to reduce carbon build up, a more efficient combustion chamber and hydraulic lifters. Traditionally a dry-sump design, lubrication was also improved for the ever faster expressways the Hydra Glide was developed for. Top speed: 105-mph. Being the largest displacement production bike made for decades placed the ‘Glide’ in rarefied air, even if (or perhaps because) Harley’s technical pace ran with a much slower clock. Its silhouette remains the symbol for motorcycling worldwide, and when properly serviced its roadholding and stability at touring speeds is admirable. Even fully loaded. Pure Americana adored everywhere, Harley’s seventy-four earns admission into the superbike hall of fame by being the only motorcycle of its kind.