Harley-Davidson FL review. Part 1.
Harley-Davidson FL review. Part 2.
Motorworld’s newspaper №63
Year 1941, the last year without war… We had only six months, USA got all that year. USA entered the WWII only after the attack on Pearl Harbor on December 7th, 1941. During eleven months of the year 1941, the Americans had been seeing another actions: New York Yankees vs. Brooklyn Dodgers and Harley-Davidson vs. Indian. New York Yankees victory had the same effect on people as a 48 h.p. Harley-Davidson FL did. FL was the mightiest bike in the whole world at the moment.

Harley-Davidson FL, 1941

The battle of Harley-Davidson vs. Indian as epic as feud between Tom and Jerry, Montague and Capulet, the Achaeans and the Trojans… At first, a Milwaukee company completely lost a market battle to a Springfield company. Before the World War I, the number of Milwaukee bikes sold was two or three times less. In the end, Harley-Davidson came out on top but it was a hard-won victory. Two competitors had been closely monitoring developments of each other and did immediate responses on every opponent’s act. In 1920s it has resulted in production mirroring: responding to a 1206 cc Indian Big Chief, a 1207 cc Harley-Davidson JD was brought on the market; a 998 cc Indian Chief has given a rise to a 989 cc Harley-Davidson J; one-cylinder 348 cc Indian Prince caused a one-cylinder 346 cc Harley-Davidson А to appear.

Harley Davidson EL from the «Motorworld by V.Sheynov» collection

In 1927 the Indian company management has made an important move: they bought the Ace company manufacturing four-cylinder William Henderson (a famous engineer) bikes. Harley-Davidson did a proportionate response: instead of designing a four-cylinder engine, they hurled all efforts into the development of an overhead valve V-twin that could be cheaper at the same dynamic performance. In 1936, the world had seen the E family equipped with 989 cc engines – a core model at 37 h.p. and a boosted engine model at 40 h.p. Harley-Davidson EL was able to accelerate to a speed of 100 mph (160.9 km/h). No bike, except the EL, could produce such a speed for such a price ($380). The market appreciated this model despite of its teething problems (oil bleeding and valve spring breakage). Also, overhead valve engine bikes were dubbed the Knuckleheads because of the appearance of valve covers. Knuckleheads were top sellers.

Harley Davidson 74 cu engine, 1941

Both ordinary bikers and police departments gladly bought the E family machines. But we know USA as a land of highways and cheap eight-cylinder cars, so the dynamics HD machines brought was not enough. By 1941, an answer to the U.S. secret service’s demand, an overhead valve bike with increased displacement was designed. It got the FL index and was equipped with a 1207 cc engine (74 cu in). This engine developed 48 h.p. at 5,000 rpm giving the excellent acceleration. But max speed was 95 mph (153 km/h) compared to an EL). The main features of FL were the same as every E-family machine had. Cast-iron cylinders & cylinder heads, assembled crankshaft with roller bearings, overhead valve drive via pushrods from the single camshaft, circulation system of lubrication (dry sump), oil tank installed under the saddle. Harley-Davidson bikes had a design feature – fork connecting rods with big ends entering each other. This solution allowed axes of cylinders to be coplanar, which decreased the engine width, reduced the main bearing load and vibrations. At this, the rear cylinder was blocked by the front one thus cooling was impaired.

 

Lubrication of the 74cu engine

The displacement was increased because of larger cylinder diameter (from 84.24 to 87.3 mm) and stroke of piston (from 88.9 to 100.8 mm). Also, a new Linkert carburettor with enhanced performance was installed (its barrel was increased from 28.5 to 33.3 mm compared to the EL model). An increased torque required a new crankcase design. Additionally, a new heavy-duty crankshaft gained 2 more kgs of weight. Modified rocker arms improved lubrication of the valve train.

 

Torque transmission was implemented via a double-strand chain going to the hand shifted four-speed gearbox installed as an individual unit. A newly designed multiple-disc clutch had an increased (by 65%) area of lining. The chassis was a strong double cradle made of pipes. The bike was equipped with a Springer fork and a spring-loaded saddle on the rigid rear suspension. Springer fork was so good that Brought Superior (an English manufacturer of “two wheeled Rolls-Royces”) bought a license for this fork. As for Harley-Davidson, it installs Springers to retro bikes even nowadays. Spring-loaded saddles used by HD were so viable & effective that soft rear suspensions appeared only in 1957. When HD started using 5.00-16 tyres (instead of previously used 4.50-18), it made an additional contribution to joy & comfort.

 

Для модельного ряда 1941 года была разработана новая панель приборов

Harley-Davidson bikes are the perfect examples of the art deco style, which was popular between WWI and WWII. FL wasn’t an exception. A drop-shaped petrol tank and elegant deep mudguards made the appearance dynamic. A metallic stripe running over the fuel tank merged into the diagonal member of the frame. A large speedometer flanked with indicating lamps has been shining on the dashboard. The lux version of a bike had a chrome plated dashboard. New silencer had a new rocket-like end (instead of the previous fishtail), which decreased the noise level and made a better appearance.

 

Apart from three wheeled Servicar, Harley-Davidson FL became the top-priced bike in the 1941 production plan – the price was $465, which is $40 more compared with an EL model). Let’s have a look at some figures for better understanding: the annual average income of an American was $515; the cheapest Ford cost $684. Nevertheless, only the WL model outsold FL. Total number of FLs sold was 2452, which is 172 units more compared to EL. But on December 7th 1941, the Japanese attacked Pearl Harbor and USA entered the WWII. The FL model didn’t make it into the military’s list of orders, that’s why the manufacturing has been frozen at the miserable level (for example, only 33 machines were manufactured in 1943). However, after the victory, the machine took its cost: 3986 FLs were sold in 1946. Again, on the WL model outsold FL.
In 1948, the Knuckleheads were replaced by the upgraded Panheads, which had hydraulic pushrods and cylinder heads made of lightweight alloy. But FL designation saw the day – it is present in the factory designation of the Harley’s Road King that considered a proximate successor of the FL from 1941.

The total number of FLs produced is 14,954 units (from 1941 to 1947). Also, some hundreds of F machines, which had a decreased compression ratio, were manufactured.

 

Manufacturer Harley-Davidson Motors Co., Milwakee (Wisconsin, USA)
Years of manufacture 1941-1947
Quantity produced, units 14 954
Price 465 $
Today’s value N/A
ENGINE AND TRANSMISSION
Type V-twin, OHV
Engine capacity, cc 1207
Bore and stroke, mm 87,3 х 100,8
Engine rating 48 hp at 5000 rpm
Sparking Battery type
Carburetor Linkert
Battery 6 V
Clutch Multiple-plate, dry
Transmission 4-speed
FRAME AND WHEELBASE
Frame type Tubular, duplex
Front suspension Springer, with frictional damper
Rear suspension Rigid
Brakes Drum type
Wheel size 5,00 x 16
DIMENSIONS
Length, mm 2300*
Width, mm 1020*
Height, mm 1130*
Wheelbase, mm 1510*
Ground clearance, mm 115*
Seat height, mm 800*
Mass, kg
 261
Gas tank size, l N/A
Maximum speed, km/h
  153
Range, km N/A

* – Data from the results of the measurement of the “Motorworld by V.Sheyanov” exhibit.

 

Thanks to the team of Harley-Davidson Russia and CIS for the provided archive photos.