Dc-Cdi; Transostorized Ignition System - Honda Motorcycle Service Manual

IGNITION SYSTEMS
DC-CDI
The DC-CDI ignition system is basically a CDI system except that the battery is used for the source. The DC-CDI ignition
control module includes a DC-DC converter which amplifies the battery voltage to about 220V, which is then stored i n the
capacitor. Except for the DC-DC converter, the DC-CDI ignition control module is identical to the CDI unit. Compared to
conventional exciter coil-powered CDI, the DC-CDI provides greater spark energy at low rpm since the power source is
stable battery energy.
IGNITION CONTROL MODULE
--
------- --
IGNITION COIL
r----
cAPAciToR1
-
I I
T
I
SPARK
4
IGNITION
PULSE
GENERATOR
spark plugs.
TRANSISTORIZED IGNITION SYSTEM
The transistorized ignition system also utilizes the battery,
but its ignition operation works differently.
Since the duration of time the spark plug fires is longer than
that of a CDI system, the transisterized ignition system is
well suited for large displacement engines.
Operating Principles
The battery feeds current t o the ignition primary coil via the
Date of Issue: March, 1995
o
HONDA MOTOR CO.,LTD.
23 -7
ignition switch and the engine stop switch when the transistor
irlside the iginition control module is turned ON. This current
is turned off when the transistor is OFF.
When the engine is turned on, the pulse signal from the
ignition pulse generator is fed to the ignition timing control
circuit. The ignition timing control circuit determines the igni-
tion timing based on the pulse signal, and sends current t o the
base of the transistor.
After current pulse flows through the primary coil, the transis-
tor is turned OFF and current to the coil is cut off. At that
moment, an induced voltage on the secondary coil ignites the
PRIMARY COIL
CURRENT