82. DESCRIPTION.

a. The ignition system differs from that of the conventional automotive types in that it has no distributor. A circuit breaker alone is used. Both coil high‐tension winding ends lead directly to both spark plugs. Thus both plugs spark at the same time, one cylinder being on compression stroke while the other cylinder is on exhaust stroke.

83. SPARK PLUGS.

a. Defective spark plugs are indicated by engine missing, overheating, knocking excessively, and lacking normal power.

b. Type. Spark plugs are medium heat range, manufacturer’s (H–D) No. 3.

c. Cleaning. Do not take plugs apart for cleaning. Use the sandblast cleaner method.

d. Point Adjustment. Bend electrode located in plug base to adjust point gap 0.025 inch to 0.030 inch.

e. Replacement. Use spark plug wrench (41–W–3334) to install plugs, using new gaskets. Never draw a cool plug up tight in a hot cylinder head, rather turn down snug and wait l/2 minute until plug base is warm: then tighten securely. CAUTION: Take care not to cross‐thread when installing spark plug.

84. CIRCUIT BREAKER POINTS (fig. 49).

a. Circuit breaker lever is insulated from ground and connects to primary wire binding post by means of a “pig‐tail” wire. Stationary point is grounded to timer base and is movable in order to adjust circuit breaker points. Circuit breaker points that are burned or pitted should be renewed or dressed with a clean fine‐cut, contact point file. The file should not be used on other metals and should not be allowed to become greasy or dirty. CAUTION: Never use emery cloth to clean points. Contact surfaces, after considerable use, may not appear bright and smooth, but this is not necessarily an indication that they are not functioning satisfactorily.

b. Remove Breaker Lever.

(1) To disconnect condenser terminal, remove nut from end of condenser and remove gear‐toothed washer, plain washer, and the brass terminal strip. Do not remove fiber washer and plain washer located back of brass terminal strip on condenser terminal post.

c. Remove Adjustable Contact Point.

(1) Remove the two lock screws and washer plate, securing adjustable contact point assembly to timer base. Point assembly is free to be lifted off lever pivot stud.

d. Install Adjustable Contact Point.

(1) Install contact point assembly, replacing washer plate and the two lock screws. Do not tighten lock screws until circuit breaker points are adjusted (step f below).

e. Install Breaker Lever.

(1) Install brass terminal strip on primary wire binding post.

(2) Connect end of brass terminal strip to condenser terminal post. Install flat washer, gear‐toothed washer, and nut.

(3) Install breaker lever on pivot post insulated bearing.

(4) Install breaker lever spring. Make sure that ends of spring are retained correctly.

(5) NOTE: Keep breaker lever cam very lightly greased.

f. Adjusting Circuit Breaker Points (fig. 51).

(1) Correct point gap is 0.022 inch. Circuit breaker point faces must seat squarely against each other. If bent, square up and aline by bending contact plate. Turn timer breaker cam until breaker lever fiber is located on highest point of cam.

(2) With the adjustable point lock screws loose, shift the adjustable point plate to obtain a 0.022–inch gap between the circuit breaker points. Measure gap with an accurate thickness gage before retightening lock screws, and again recheck point gap after tightening the lock screws. NOTE: Wrong circuit breaker point gap affects ignition timing.

85. CONDENSER.

a. The condenser is connected in parallel with the circuit breaker points, one of its terminals being grounded (for the adjustable point) to the timer base by means of the mounting screw, the other terminal making connection with the circuit breaker lever (for the lever point) by means of the lever “pig‐tail.”

b. Remove.

(1) Unlatch circuit breaker cover retainer and remove cover.

(2) Remove nut from end of condenser and remove gear‐toothed washer, plain washer, and the brass terminal strip. NOTE: A small plain washer and a large fiber washer are located behind brass terminal strip.

(3) Remove screw which secures condenser to timer base. Remove condenser.

c. Install.

(1) Mount condenser on timer housing. Install lock washer and screw. Make sure small plain washer and large fiber washer are in place on condenser end terminal screw before connecting the brass terminal strip.

(2) Connect brass terminal strip to condenser. Replace plain washer, gear‐toothed washer and terminal nut.

(3) Install circuit breaker cover.

86. CIRCUIT BREAKER AND TIMER ASSEMBLY (figs. 50 and 51).

a. When the circuit breaker timer shaft and base assembly must be replaced due to excessive wear in timer shaft bearing, sheared worm gear pin, and/or worn or damaged worm gear, engine ignition must be retimed. Ignition timing for the V‐type twin engine is difficult and should be attempted only by experienced personnel.

b. Remove (fig. 50). Before the timer shaft and base assembly can be removed, the circuit breaker timer head assembly must be removed. NOTE: If the timer head only, or timer wire, is to be replaced, it is not necessary to remove timer shaft and base assembly, and thus throw engine ignition out of time.

(1) Remove timer head cover.

(2) Unlatch cover retainer ends from holes in the timer head and remove.

(3) Disconnect spark control wire at timer lever.

(4) Lift the timer head assembly off base. The head seating tension (ground) spring (underneath shaft base) is also free, and can now be removed. NOTE: It is not necessary to disconnect timer to coil wire from timer head terminal post, unless head or wire is being replaced.

(5) Remove the two timer base mounting screws and lock washers. It will be noted that one screw grounds the timer to coil wire shielding.

(6) Timer shaft and base assembly can now be lifted out of engine gear case cover. Take care not to damage or misplace base gasket.

c. Install Timer Shaft and Base Assembly and Timing Ignition (fig. 51). This calls for retiming engine ignition as follows: (NOTE: Circuit breaker cam turns in clockwise direction):

(1) Unscrew and raise front cylinder inlet valve spring cover, using tappet wrench (41–W–3617).

(2) Turn engine in direction in which it runs until valve tappet indicates front cylinder is on compression stroke (directly after front cylinder intake valve closes).

(4) Continue turning engine slowly until flywheel timing mark is in center of inspection hole (fig. 51). Do not turn engine further.

(5) Install paper gasket and timer head tension (ground) spring on timer shaft base assembly. Make sure bent ends of tension spring are facing downward (away from timer base).

(6) Insert timer shaft and base assembly all the way down into place in timing gear case cover, trying to locate mark on small end of breaker cam in position shown in figure 51. Do not install base mounting screws as yet.

(7) Install timer head assembly so that spark control lever is within the advance and retard quadrant (fig. 51). NOTE: Do not install cover retainer until later.

(8) Fully advance spark lever (push inward toward engine) and observe how closely mark on breaker cam lines up with breaker lever fiber. If mark does not line up, lift timer base and turn shaft gear so its engagement with its driving gear is changed one tooth. Check again according to breaker cam mark and breaker lever fiber. Repeat this procedure until gear engagement is obtained which closely alines cam mark and breaker lever fiber.

(9) See that timer base is turned so that timer to coil wire is toward rear of engine.

(10) Install timer base screws and lock washers. Make sure that timer to coil wire shielding is grounded under head of screw farthest away from engine (fig. 52). Securely tighten screws.

(11) Install timer head on base and secure with ground spring and cover retainer. Be sure ground spring is in its proper place so that when cover retainer ends are fitted through holes in the timer head, they will also fit into spring locating notches. It will be necessary to press ground spring upward under timer base to engage retainer ends in the spring notches. NOTE: If cover retainer ends do not engage ground spring notches, spring will have no tension and timer head will be loose on its base. Circuit breaker points and condenser are electrically grounded through timer base, and ground spring holds the head and base in close contact, thus assuring a good ground.

(12) Connect spark control wire and timer lever and adjust (par. 88).

(13) Engine is now timed according to original factory setting, providing mark on side of timer head and hole in head adjusting band are still in alinement, and circuit breaker point gap is 0.022 inch. Even though all ignition timing marks are in perfect alinement, as outlined in the foregoing instructions, it is advisable to accurately check ignition timing (step d following).

d. Recommended Recheck of Ignition Timing (fig. 51). Even though all ignition timing marks are in perfect alinement, as when engine was originally timed, ignition timing may change somewhat after engine has been in service for a while, due to normal wear and seating of the various moving parts that can affect ignition timing. Since accurate ignition timing is the first essential to good engine performance, it is advisable to check ignition timing on new vehicle after first 1,500 miles of service, and at each 2,000 miles thereafter.

(1) See that circuit breaker points are adjusted for correct gap of 0.022 inch (par. 84 f).

(2) Advance timer lever fully (toward engine).

(3) Turn engine in direction in which it runs until front cylinder is on compression stroke, and continue to turn it ahead slowly until narrow timer cam (the end with the timing mark), just starts to open the circuit breaker points.

(5) When exact position is found, where points just start to open, flywheel mark should be in the center of the inspection hole.

(6) If flywheel mark is not in center of hole when points open, readjust ignition timing as necessary (slower or faster) by means of the timer head and band adjustment.

(8) With ignition timing correct, front cylinder piston is 9/32 inch before top dead center, on compression stroke, when circuit breaker points just start to open. At this point spark occurs, igniting front cylinder fuel charge.

(9) Install flywheel inspection hole plug in left crankcase.

87. COIL TO TIMER WIRE (figs. 52 and 53).

a. Models provided with radio shielding are identified by “S” on either side of instrument panel. The coil to timer wire (low‐tension wire) on these models is shielded for radio noise suppression.

b. Remove.

(1) Disconnect battery negative ground wire at frame connection.

(2) Remove the two bolts which secure upper end of air cleaner bracket to frame tube. Swing air cleaner and bracket outward and forward to gain access to spark coil rear terminal.

(3) Disconnect coil to timer wire terminal from coil rear connection. Disconnect wire shielding from coil rear ground connection.

(4) Refer to paragraph 86 b (1) to (4) for timer head removal.

(5) Remove timer base mounting screw which secures wire shielding (fig. 52).

(6) Note position of coil to timer wire inside of timer head; then remove nut washer connecting wire to insulated contact stud.

(7) Work old wire and loom out of timer head hole and free from vehicle.

(8) On earlier models, the coil to timer wire was soldered to end of insulated stud. Removal of stud is necessary to remove this wire, or replace it with a shielded wire. Note location of stud insulations on inside and outside of timer head, for correct installation when reassembling.

c. Install.

(1) Pass end of wire, shield terminal, and loom up through hole in timer base.

(2) Ground the wire shield terminal under head of timer base mounting screw (fig. 52).

(3) Connect wire end terminal to insulated stud so that wire leads away from stud in direction shown (fig. 52).

(4) Pass coil to timer wire up alongside and to rear of frame saddle post tube to reach rear of spark coil.

(5) Ground the wire shield terminal to coil rear ground connection (fig. 53).

(6) Connect wire terminal to coil rear primary connection (fig. 53).

(7) Install timer head on base (par. 86 c (11)).

(8) Connect spark control wire to timer lever and adjust (par. 88).

(9) Connect battery negative post wire to frame ground terminal.

(10) Swing air cleaner bracket back into place and install two bolts, washers, and nuts securing bracket to frame clips.

(11) Replace timer cover and check engine for starting.

88. ADJUST SPARK CONTROL.

a. Spark advance and retard is controlled by left handle bar grip. Spark lever operates within a quadrant mounted on engine. Spark must be fully advanced (lever inward toward engine) when handle bar grip is turned inward to full extent of its travel. When handle bar grip is turned outward, spark lever retards (lever outward away from engine).

(1) With control wire in lever stud and clamp screw loose, turn left grip fully inward; then back it out just a little.

(2) Shift spark lever inward toward engine as far as it will go; then tighten control wire clamp screw. Test by turning left grip fully inward and noting position of spark lever. It should be against inner side of quadrant (fig. 51). Retard spark and check position of lever within quadrant; it should be against outer side of quadrant.

(3) Check final adjustment. Readjust full advance and retard timer lever positions as necessary when left grip is turned inward, and outward, respectively.

89. SPARK COIL (fig. 54).

a. Spark coil high‐tension cables go directly to the spark plugs, no distributor being used. When the coil is faulty, it must be replaced, since internal repairs are not possible. The high‐tension cables can be replaced, however. Coil is provided with a condenser for radio noise suppression, and metal coil case is grounded to engine by bonding.

b. Remove.

(1) Disconnect battery negative ground wire from frame connection.

(2) Free high‐tension cable ends (with radio noise suppressors) from spark plugs. Free front cylinder high‐tension cable from clip at upper engine frame mounting.

(3) Loosen air intake hose connection at carburetor fitting.

(4) Remove two nuts, washers, and bolts securing upper end of air cleaner mounting bracket to frame clamps.

(6) Disconnect coil to timer wire from coil rear terminal screw. Disconnect wire shielding from coil rear ground terminal (fig. 53).

(7) Swing cleaner back and remove wire connections from coil front terminal screw (fig. 54).

(8) Disconnect radio bonding at coil front ground terminal (fig. 54).

(9) Remove nuts and bolts which mount coil to bracket. Coil is now free for removal.

c. Install.

(1) Mount coil on frame bracket with high‐tension cables upward, and reinstall mounting bolts, lock washers, and nuts. Tighten nuts.

(2) Connect terminals of the two green wires to coil front terminal screw. Refer to wiring diagram, figure 48.

(3) Connect radio bonding to coil front ground terminal. Tighten nut securely.

(4) Connect coil to timer wire terminal to coil rear terminal screw. Connect wire shielding to coil rear ground terminal. Tighten nut securely.

(5) Swing air cleaner and bracket assembly back in place and install two bolts, lock washers, and nuts securing bracket to frame clamps. Tighten nuts securely.

(6) Connect battery negative ground wire to frame connection.

(7) Pass front cylinder high‐tension wire under tank, secure in cable clip at upper engine frame mounting, and attach cable end (radio noise suppressor) to front spark plug. Attach rear high‐tension cable end (radio noise suppressor) to rear spark plug.

(8) Check wiring connections (fig. 48) and test coil by engine starting.