PART ONE—OPERATING INSTRUCTIONS
Section I
INTRODUCTION
Paragraph Scope 1 Supersession of quartermaster manuals 2
1. SCOPE.
=a.= This technical manual[2] is published for the information and guidance of the using arm personnel charged with the operation, maintenance, and minor repair of this materiel.
=b.= In addition to a description of the Harley‐Davidson motorcycle, this manual contains technical information required for the identification, use, and care of the materiel. The manual is divided into two parts. Part One, section I through section VI, gives vehicle operating instructions. Part Two, section VII through section XXV, gives vehicle maintenance instructions to using arm personnel charged with the responsibility of doing maintenance work within their jurisdiction.
=c.= In all cases where the nature of the repair, modifications, or adjustment is beyond the scope or facilities of the unit, the responsible ordnance service should be informed so that trained personnel with suitable tools and equipment may be provided, or proper instructions issued.
2. SUPERSESSION OF QUARTERMASTER MANUALS.
=a.= This technical manual, together with TM 9-1879, supersedes and replaces the following Quartermaster Corps publications:
(1) TM 10-1175—Maintenance manual, motorcycle, solo, Harley‐Davidson (Model 42-WLA), 11 September 1941.
(2) TM 10-1177—Maintenance manual, motorcycle, solo, Harley‐Davidson (Models 1940-41-42), 11 September 1941.
(3) TM 10-1331—Maintenance manual, motorcycle, chain drive Harley‐Davidson (Model 42 WLA, solo).
(4) TM 10-1359—Instruction folder (45-A) motorcycles, solo, Harley‐Davidson (Model 1941 WLA 45), 25 November 1941.
(5) TM 10-1361—Instruction folder (45-B) motorcycle, solo, Harley‐Davidson (Model 1941 WLA 45), 25 November 1941.
[Footnote 2: To provide operating instructions with the materiel, this technical manual has been published in advance of complete technical review. Any errors or omissions will be corrected by changes or, if extensive, by an early revision.]
Section II
DESCRIPTION AND TABULATED DATA
Paragraph Description 3 Data 4
3. DESCRIPTION (figs. 1, 2, and 3).
=a.= This 2‐cylinder solo motorcycle is powered by a V‐type, air‐cooled gasoline engine, operating on conventional 4‐stroke, 4‐cycle principles. Air‐cooled engines rely upon movement of air over cylinder and head radiating fins, and upon circulation of oil for dissipation of excessive heat. Motorcycle engines, therefore, under no conditions should be operated for more than 1 minute when motorcycle is not in motion.
4. DATA.
=a. Vehicle Specifications.=
Type of engine 2‐cylinder, V‐type L‐head, air‐cooled Cylinder bore 2-3/4 in. Stroke 3-13/16 in. Engine number (serial) left side engine base, below front cylinder. Wheelbase 4 ft 11-1/2 in. Length over‐all 7 ft 4 in. Width over‐all (handle bars) 3 ft 5 in. Wheel size 18 in. Tire size 4.00 × 18 in. Tire type Drop center Weight of vehicle (without rider or armament) 540 lb. Ground clearance (skid plate) 4 in. Kind and grade of fuel Gasoline: 72 octane or higher High gear ratio 4.59:1 Engine sprocket 31‐tooth Countershaft sprocket 17‐tooth Rear wheel sprocket 41‐tooth
=b. Performance.=
Maximum allowable speed 65 mph Miles per gallon (hard surface) 35 Cruising range (without refill) 100 miles Fording depth (carburetor) 18 in.
=c. Capacities.=
Fuel capacity (left tank) 3-3/8 U.S. gal Oil tank capacity (right tank) 1-1/8 U.S. gal Transmission capacity 3/4 pt
Section III
CONTROLS AND OPERATION
Paragraph Controls 5 Engine prestarting instructions 6 Starting the engine 7 Stopping the engine 8 Operation of vehicle 9 Driving precautions 10 Stopping and parking vehicle 11 Towing vehicle to start engine 12 Running‐in new engine (or vehicle) 13
5. CONTROLS (fig. 4).
=a.= Controls are peculiar to the motorcycle. The rider must become thoroughly familiar with the location and use of all control devices before attempting to operate vehicle.
=b. Gasoline Valve= (figs. 5 and 6). Gasoline valve is located in left tank, forward. Valve is closed by turning to the right, finger tight. Turning to left opens valve. Valve is in normal operating position when turned to left, with valve head down. Lifting valve head releases emergency supply of fuel (3 quarts).
=c. Throttle.= The throttle is controlled by right handle bar grip. Turning grip inward opens throttle, turning it outward closes throttle.
=d. Spark.= Spark is controlled by left handle bar grip. Turning grip inward advances spark, turning it outward retards spark.
=e. Clutch= (fig. 7). Clutch is operated by left foot (rocker‐type) pedal, connecting with steel cable, which actuates clutch release lever. Pedal is located on left side of motorcycle above footboard. Forward downward (toe) position of pedal engages clutch. Rear downward (heel) position of pedal disengages clutch. Foot pedal provided with friction device to retain it in either engaged or disengaged position.
=f. Service Brake (Rear Wheel).= Foot pedal is located on right side of motorcycle at forward end of footboard.
=g. Auxiliary Brake (Front Wheel).= Auxiliary brake is operated by hand lever located on left handle bar. It is used in conjunction with service brake, as an emergency brake, or for holding vehicle while starting engine on grade. CAUTION: Brake is to be applied lightly and cautiously on wet and slippery roads.
=h. Gear Shifter= (fig. 8). Shifter lever is located on left tank, forward position, and operates within a guide. Shifter lever guide is notched for positive location of gears and each position is identified, front to rear: “1”—low gear; “N”—neutral; “2”—second gear; “3”—direct high gear.
=i. Steering Damper.= Steering damper is an adjustable friction device to damper turning action of forks, steady front wheel, and prevent wobble in rough terrain or at high speeds, and is located on top of steering head in center of handle bars. Move handle to right to apply desired friction.
=j. Foot Starter Crank= (fig. 1). The foot starter crank is located on right side of motorcycle. Gear shifter lever must be in neutral position, and clutch foot pedal in forward engaged position, before using foot starter crank. Starter crank normally is in upward position. Straddle motorcycle, place right foot on starter crank, and shift weight of body for forceful downward crank operation to start engine.
=k. Ignition and Light Switch.= Earlier models are provided with switch lock, later models are nonlocking. Switch is off in straight‐forward position. First position to right is for engine ignition only. Second position to right is for ignition and blackout lights. To use vehicle service lights, depress button to turn switch to third right position.
=l. Instrument Panel Signal Lights.= Instead of an ammeter and oil pressure gage, signal lights indicate generator charging, and engine oil pressure.
(1) Green light is located on left side of instrument panel. When engine is running, and light is out, it indicates generator is charging.
(2) Red light is located on right side of instrument panel. When engine is running, and light is out, it indicates engine oil is circulating.
=m. Carburetor Choke= (fig. 9). Choke lever is in full prime position when all the way up, and in normal running position when all the way down.
6. ENGINE PRESTARTING INSTRUCTIONS.
=a.= Before the engine is started, perform the Before‐operation Service outlined in paragraph 15. Special care must be taken during starting and warming‐up period to avoid unnecessary engine wear.
=b.= The rider must acquire correct motorcycle engine starting habits, and learn to do the job the quickest, easiest, and most dependable way. The following pointers will be helpful to the beginner as well as to a seasoned rider:
(1) Mount (straddle) motorcycle to obtain firm grip on handle bars.
(2) Leave side stand (jiffy stand) outward to support vehicle while operating foot starter crank with right foot.
(3) Engine starting will be benefited by use of front wheel, hand‐operated brake, to prevent vehicle from rolling or shifting during starting kicks. This is especially helpful if vehicle is parked on an incline or on soft, uneven surface.