Buell 2002 S3T, Service Manual

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5-2 2001 Buell S3/S3T: Electric Starter
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ELECTRIC STARTER SYSTEM 5.2
GENERAL
The starter is made up of an armature, field winding assem-
bly, solenoid, drive assembly, idler gear and drive housing.
The starter motor torque is increased through gear reduction.
The gear reduction consists of the drive pinion on the arma-
ture, an idler gear and a clutch gear in the drive housing. The
idler gear is supported by rollers. The clutch gear is part of
the overrunning clutch/drive assembly.
The overrunning clutch is the part which engages and drives
the clutch ring gear. It also prevents the starter from overrun-
ning. The field windings are connected in series with the
armature through brushes and commutator segments.
Wiring Diagrams
For additional information concerning the starting system cir-
cuit, see the wiring diagram at the end of Section 7, ELEC-
TRICAL.
Starter Relay
The starter relay is not repairable. Replace the unit if it fails.
OPERATION
See Figure 5-1. When the starter switch is pushed, the starter
relay is activated and battery current flows into the pull-in
winding (10) and the hold-in winding (11), to ground.
The magnetic forces of the pull-in and hold-in windings in the
solenoid push the plunger (7) causing it to shift to the left.
This action engages the pinion gear (1) with the clutch ring
gear (13). At the same time, the main solenoid contacts (8)
are closed, so battery current flows directly through the field
windings (3) to the armature (4) and to ground. Simulta-
neously, the pull-in winding (10) is shorted.
The current continues flowing through the hold-in winding
(11) keeping the main solenoid contacts (8) closed. At this
point, the starter begins to crank the engine.
After the engine has started, the pinion gear (1) turns freely
on the pinion shaft through the action of the overrunning
clutch (12). The overrunning clutch prevents the clutch ring
gear (13) (which is now rotating under power from the
engine) from turning the armature (4) too fast.
When the starter switch is released, the current of the hold-in
winding (11) is fed through the main solenoid contacts (8)
and the direction of the current in the pull-in winding (10) is
reversed. The solenoid plunger (7) is returned to its original
position by the return spring, which causes the pinion gear
(1) to disengage from the clutch ring gear (13).