The motorcycle was originally single-speed. In 1909, a two-speed transmission was offered,^[12] then three-speed in 1914 with the 748 cc engine.^[13] It had a single-speed shaft drive turned by a bevel gear.^[10] The rider started the engine by pedaling bicycle style pedals with a chain drive and sprockets to the rear wheels.^[13] The 1905 model had a high-tension Bosch magneto ignition,^[14]: 43 a spray carburetor, and a rear coaster brake operated by the pedals.^[10] It had a 5:1 reduction ratio to 26-inch wheels.^[14]

By 1908, it had a two speed transmission with a plate clutch, overcoming the speed limitations of the earlier model.^[10] In 1909 a rear drum brake was fitted.^[13] In 1910 the engine was redesigned and enlarged to 498 cc (30.4 cu in), the carburetor was moved and a new oiling system was used.^[13] The weight in 1910 was 165 lb (75 kg).^[7]

For the US market, the 1908 model was upgraded and released as a 19081⁄2 model, called the F.N. Big Four.^[15] Engine power was raised from 4+1⁄2 hp (3.4 kW) to 5 hp (3.7 kW), the frame size was reduced from 22 to 20 inches (560 to 510 mm) allowing the rider to sit with both feet on the ground, the wheel rims were made heavier and would fit American tire sizes, and it came with tires with a heavier tread.^[15]

The 1911 model weighed 185 lb (84 kg) and had a wheelbase of 56 in (1,400 mm).^[14]: 43 The US model had either Goodrich or another imported brand of tires, and a leather seat made by the Mesinger Bicycle Saddle Company of New York.^[14]: 43 By 1911 bore × stroke was up to 2+1⁄16 in × 2+1⁄16 in (52 mm × 52 mm) and nominal output was up to 6 hp (4.5 kW).^[14]: 20

The motorcycle had bicycle-style pedals used for starting until 1913, when a kickstarter was adopted.^[13]

Four-cylinder engine edit

The FN Four's engine was designed by Paul Kelecom, who had designed single-cylinder engines prior to the FN.^[16] The air-cooled longitudinal layout was prone to overheating the rear cylinders, a trait overcome in later designs with water cooling and transverse layout.^[17]

FN originally fitted the Four with a 350 cc^[16] or 362 cc^[13] engine. The displacement increased over time, to 410 cc in 1906,^[18] later to 498 cc for the US market, and a 748 cc variant was produced in 1914. The engine had to be periodically oiled with a hand pump during riding.^[16] The intake valves were atmospheric, pushed open by ambient air pressure against light springs during the piston's intake stroke,^[16] up to the 1914 748 cc model, which replaced the automatic inlet valves with mechanically actuated side valves.^[13]

First four-cylinder motorcycle? edit

[A]lthough there were four-cylinder motorcycles prior to the FN, none came near matching the eminently successful and practical performance of the FN right from the beginning.

— T.A. Hodgdon, Motorcycling's Golden Age of the Fours, 1976

The FN Four was the first production inline-four, but not the first motorcycle with a four-cylinder engine. It was preceded by a boxer 4 manufactured in 1897 by Henry Capel Lofft Holden,^[19][20] and an obscure air-cooled inline-four developed in 1903 by C. Binks of Nottingham, England, but never produced commercially.^[11][20] A longitudinally mounted four-cylinder "model CCCC" prototype was created by Laurin & Klement and shown in Paris in 1904, but it was essentially four ganged single-cylinder engines with four separate crankshafts, not an inline-four in the modern sense.^{[21][22][23][24]} The FN, at the time of its introduction, was the only four-cylinder motorcycle for sale in America.^[25] (later Henderson Motorcycle sold a four from 1912 until 1931.)

Comparable motorcycles edit

• Pierce Four
• Indian Four
• Henderson Motorcycle Four

The success of the FN Four directly led the US Pierce Four to use the same engine mounted longitudinally with a shaft drive.^[5] Pierce-Arrow's Percy Pierce brought a 1908 FN Four home from Europe to disassemble and study.^[5][27] Indian, Henderson and Cleveland fours were all said to have been inspired by the FN Four.^[28]

Early examples of the machine are rare; a 1904/1905 model, reported to be the earliest known example, sold at a record price in a 2006 auction for over US$100,000.^[29]

Race history edit

A FN Four took third place in the 1908 Isle of Man TT,^[30] and was the first four-cylinder-engine vehicle entered at the Isle of Man TT.^[9] In 1908 another FN Four took the gold medal in a Motor Cycling Club endurance race on the 1,400-kilometre (870 mi) London–Edinburgh–London course.^[31]

Museum exhibits edit

An FN Four was exhibited at the Guggenheim Museum's The Art of the Motorcycle exhibition in New York and Las Vegas. Models are in the permanent collections of Petersen Automotive Museum in Los Angeles,^[32] Seal Cove Auto Museum in Seal Cove, Maine,^[33] the Musée de la moto et du vélo in Amnéville France,^[34] and others.

• List of motorcycles of the 1910s
• List of motorcycles of 1900 to 1909

• Brown, Roland (2006), The Ultimate History of Fast Bikes, Bath, UK: Parragon, ISBN 1-4054-7303-7
• Cameron, Kevin (January 19, 2012), "The Five Greatest Motorcycles", Cycle World
• Caunter, C. F. (1955), The History and Development of Motorcycles; As illustrated by the collection of motorcycles in the Science Museum; Part I Historical Survey, London: Her Majesty's Stationery Office, OCLC 11506035
• de Cet, Mirco, ed. (2002). The Illustrated Directory of Motorcycles. St. Paul, Minnesota USA: Salamander Books. ISBN 0-7603-1417-9.
• "The F. N. Four-Cylinder Motor-Cycle", Cycle and Automobile Trade Journal, 11 (1), Philadelphia: Chilton, July 1906
• "The 1909 'F. N.' Big Four", Cycle and Automobile Trade Journal, 13 (12), Philadelphia: Chilton, June 1909
• Duckworth, Mick, ed. (2012), Motorcycle: The Definitive Visual History, Dorling Kindersley, pp. 26–29, ISBN 978-0756690526
• Edwards, David (August 1997), "Four-runners: the essential guide to inline-fours", Cycle World, pp. 42–43
• Hodgdon, Ted A. (1976), Motorcycling's Golden Age of the Fours (third ed.), Lake Arrowhead, California: Bagnall Publishing Company, ASIN B0006CR2Q2
• Hough, Richard Alexander; Setright, L.J.K. (1966), A history of the world's motorcycles, New York: Harper & Row, LCCN 66018583
• Isle of Man Weekly Times, p. 4, 29 September 1908 {{citation}}: Missing or empty |title= (help)
• Kirchberger, Michael; Ludewig, Christoph (2007), Katrin Thoss (ed.), Škoda: bewegte Geschichte seit über 100 Jahren (in German), Plexus-Verlag, ISBN 9783937996097
• Solomon R. Guggenheim Museum; Field Museum of Natural History; Museo Guggenheim Bilbao (2001), Krens, Thomas (ed.), The Art of the Motorcycle, Guggenheim Museum, ISBN 978-0-8109-6912-4
• Malanik, Pavel, Historic vehicle Laurin & Klement CCCC 1904 on YouTube, uploaded 2008
• Mitchell, Leon (1998), "Four cylinder FNs 1905-1914", Leon Mitchell's vintage motorcycle page, Adelaide, South Australia, retrieved 2013-10-18
• "Belgian engineers visit U.S.", Motor Age, 30 (15), Chicago, October 12, 1916
• Motorcycle Illustrated, vol. 6, The Motorcycle Publishing Co., January 12, 1911
• "New F.N. Motorcycle Model", The Horseless Age: The Automobile Trade Magazine, vol. 22, no. 7, Horseless Age Company, p. 204, 1908, retrieved October 19, 2013
• d'Orléans, Paul (August 26, 2008), "First 4-cylinder racer at the Isle of Man", The Vintagent, retrieved 2013-10-17
• d'Orléans, Paul (May 27, 2013), "Vintage-Revival Montherly 2013", The Vintagent, retrieved 2013-10-20
• 1904 FN Four, Los Angeles: Petersen Automotive Museum, archived from the original on 2013-08-16, retrieved 2013-10-20
• "Auction Of Late Actor Steve McQueen's Motorcycles Brought Record Prices", Roadracing World, November 20, 2006, retrieved 2013-10-20
• Walker, Mick (2000), "Chapter 2: Belgium", Mick Walker's European Racing Motorcycles, Low Fell: Redline Books, ISBN 9780953131136
• Walker, Mick (2006), Motorcycle: Evolution, Design, Passion, JHU Press, p. 28, ISBN 0-8018-8530-2

• Duchateau, Egon; Geert Huylebroeck; Nick Jonkheere; Rick van Eycken; Luc Freson (2008). A-Z der Belgische motoren (in Dutch). Motorboeken uitgeverij Freson. ISBN 978-907734-6105.
• Rauch, Siegfried (1980). Berühmte Rennmotorräder (in German) (second ed.). Stuttgart: Motorbuch Verlag. ISBN 978-3879435906.
• Tragatsch, Erwin (1977). The Complete Illustrated Encyclopedia of the World's Motorcycles. Holt, Rinehart and Winston. ISBN 978-0030192968.
• Tragatsch, Erwin (1997). Alle Motorräder 1894-1981: Eine Typengeschichte. 2500 Marken aus 30 Ländern (in German). Stuttgart. ISBN 3-87943-410-7.{{cite book}}: CS1 maint: location missing publisher (link)

•   Media related to FN Four at Wikimedia Commons
• High resolution images, 1914 model, Bonhams