Suzuki DF 90 Service Manual page 61

IGNITION TIMING CHART
The following chart is an example for ignition at BTDC 30°.
34-signals/360˚
10˚
CKP sensor
signal
CMP sensor
signal
ON
#1 ignition
OFF
signal
In.
#3 ignition
signal
Ex.
#4 ignition
signal
Ep.
#2 ignition
signal
Cm.
In. : Intake, Cm. : Compression,
CONTROL MODE
WHEN CRANKING :
The ignition timing is fixed at BTDC 5° until the engine starts.
WHEN IDLING / TROLLING :
The ignition timing is controlled within the range of BTDC 3° to 13° to provide stable engine operation at the
specified idling / trolling speed.
When the shift lever is in neutral, if engine speed exceeds 900 r/min., ignition timing remains fixed at BTDC
8°.
WHEN RUNNING (NORMAL OPERATION) :
The ignition timing ranges between BTDC 1° – 44° (DF90) or BTDC 3° – 44° (DF115), depending on current
engine operating conditions.
WHEN DECELERATING :
When the throttle valve is closed suddenly, turning the CTP switch "ON", the return of ignition timing to the
closed throttle specification (idle speed) is delayed for a programmed duration to prevent engine stalling or
unstable running.
SPECIFICATION
Ignition system
Advance
Ignition timing
Firing order
30˚
120˚ 120˚
4-signals/720˚
30˚
Cm. Ep.
TDC
In. Cm.
TDC TDC
Ex. In.
TDC
Ep. Ex.
TDC TDC
ENGINE CONTROL SYSTEM
120˚
Ex. In. Cm.
TDC
Ep. Ex.
TDC
Cm. Ep. Ex.
TDC
In. Cm. Ep.
TDC
Ep. : Explosion, Ex. : Exhaust,
Full-transistorized ignition
Electronic microcomputer control
DF 90 : BTDC 1° – 44°,
1 – 3 – 4 – 2
Spark timing
Ep. Ex.
TDC
In. Cm. Ep.
TDC
In. Cm.
TDC
Ex. In.
TDC
TDC : Top Dead Center
DF 115 : BTDC 3° – 44°
3-13
In.
TDC
Ex.
Ep.
TDC
Cm.