Arctic Cat 660 cc, Service Manual

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5-2
BASIC ELECTRICAL
SPECIFICATIONS CHART
Testing Components
Following are testing procedures for specific electrical
components. For additional testing procedures and
specifications for the 660 cc models, refer to the Arctic
Cat Diagnostic System Manual (p/n 2256-974).
All tests of the engine electrical components should be
made using the digital Fluke Model 73 Multimeter
(p/n 0644-191). Replace any component that does not
have a test value within specifications.
„
NOTE: Whenever using a digital-style tester,
“open (infinite resistance)” denotes an overload
and the meter reading will be OL since the meter is
not calibrated to register resistance values of that
magnitude.
„
NOTE: Whenever testing switches, less than 1
ohm is desirable with the switch in the activated
position.
Transistorized Ignition
System
(120 cc)
The transistorized ignition system has no contact
points. Therefore, this ignition system does not require
periodic reconditioning of contact point surfaces or
point gap adjustment. As a result, a strong spark is pro-
duced even at low speeds so maximum reliability can
be ensured.
OPERATION
GEN-0008
When the recoil starter handle is pulled, the flywheel is
turned. An electromotive force generated in the pri-
mary winding of the ignition coil makes the transistor
(TR1) conduct through the resistor (R) and forms the
primary circuit (indicated by dashed lines).
As the flywheel turns faster, the primary current
increases, and the terminal voltage of the circuit con-
sisting of the resistor (R) and the transistor (TR1)
increases. This increases the working voltage at the
connection of the series circuit (r1 + r2) connected in
parallel to the primary circuit. As the flywheel turns
further, the terminal voltage of the resistor (r2) in the
resistor circuit (r1 + r2) rises to the level of working
voltage of the transistor (TR2) when the ignition tim-
ing approaches the rated RPM, and, thus, the transistor
(TR2) is turned on. As a result, the base current of
(TR1) flowing through the resistor (R) is by-passed,
and the transistor (TR1) is turned off from the conduc-
tive state.
The current flowing through the primary winding (2)
is thus interrupted, and rapid change occurs in the
magnetic flux across the ignition coil. The result is a
high surge voltage in the secondary winding (3).
MODEL
ENGINE
MODEL
IGNITION
MANUFACTURER
SPARK PLUG
(NGK)
SPARK PLUG GAP
IGNITION
TYPE
ALTERNATOR
OUTPUT
mm in.
120 cc AA12A1 Kokusan Denki BPR6ES 0.07-0.08 0.028-0.031 TRANSISTORIZED 12V/55W
Bearcat W/T K6A-B Kokusan Denki KR8AI 0.07-0.08 0.028-0.031 OPEN 12V/878W
660 cc Standard K6A-B Kokusan Denki KR8AI 0.07-0.08 0.028-0.031 OPEN 12V/870W
660 cc Turbo K6A-B Kokusan Denki KR8AI 0.08-0.09 0.031-0.035 OPEN 12V/870W