Polaris INDY TRAIL RMK Service Manual page 17

GENERAL INFORMATION
Heat Exchanger: A device used to transfer heat. They dissipate engine heat to the atmosphere.
Hex Head Bolt: Standard type of wrench-applied hexagon head, characterized by clean, sharp corners trimmed
to close tolerances. Recommended for general commercial applications.
Hi-Fax: Trademark of Himont Advanced Materials. The special slide material which fits onto the bottom of the
suspension rails.
High Side: Sled pushes or tips up toward outside of turn.
High Tension Wire: The heavy insulated wire which carries the high secondary voltage from the coil to the spark plug.
Hole Shot: A term used when machine starts a race from a dead stop.
Holed Piston: Piston in which a hole has formed on the dome. Possible causes: 1) detonation; 2) pre-ignition.
Ignition Coil: A type of transformer which increases voltage in the primary windings (approx. 200V) to a higher voltage
in the secondary windings (approx. 14KV - 32KV) through inductions. Secondary voltage is high enough to arc the air
gap at the spark plug.
Ignition Generating Coil: Exciter coil or primary charge coil. Stator plate coil which generates primary ignition voltage.
CDI system uses one ignition generating coil.
Inch Pound: In. lb. 12 in. lbs. = 1 ft. lb.
Kg/cm2: Kilograms per square centimeter. Metric equivalent of PSI.
Keystone Ring: A piston ring with bevel on upper surface.
Kilogram/meter: A force of one kilogram at the end of a lever one meter in length, applied in a rotational direction.
Metric equivalent of ft. lbs.
L Ring: A wide face piston ring with an "L" shaped cross section. Leg of "L" goes up when installing on piston.
Labyrinth Seal: A pressure type center seal identified by series of grooves and lands. Polaris engines us this type of
seal to separate the cylinders in the crankcase halves.
Left Side: Always referred to based on normal operating position of the driver.
Lighting Coil: Generates voltage for lights, battery charging, etc by electromagnetic induction.
Loose: When the rear of the vehicle slides outward in a turn. The track does not grab sufficiently.
mm: Millimeter. Unit of length in the metric system. 1mm = .040".
Mag End: Flywheel side of engine.
Magnetic Induction: As a conductor (coil) is moved through a magnetic field, a voltage will be generated in the
windings. This is how mechanical energy in our engines is converted to electrical energy in the lighting coil, ignition
generating coils and trigger coil.
Ohm: The measurement of electrical resistance opposing current flow.
Oval Head Screw: Fully specified as "oval countersunk", this head is identical to the standard flat head, but
possesses a rounded upper surface for attractiveness of design.
PTO End: Power Take Off drive (clutch side).
Pan Head Screw: Provides a low, large diameter head, but with characteristically high outer edges along the
outer edge of the head where driving action is most effective. Slightly different head contour when supplied with Phillips
Recess. See dotted line.
Piston Clearance: Total distance between piston and cylinder wall.
Piston Erosion: Piston dome melts. Usually occurs at the exhaust port area. Possible causes: 1) lean fuel/air mixture;
2) improper spark plug heat range; 3) Poor fuel.
Pre-Ignition: A problem in combustion where the fuel/air mixture is ignited before normal spark ignition. Piston looks
melted at area of damage. Possible causes: 1)incorrect spark plug heat range; 2) spark plug not properly torqued; 3)
"glowing" piece of head gasket, metal burr or carbon in the combustion chamber; 4) lean fuel/air mixture; 5) Incorrect
ignition timing.
Primary Circuit: This circuit is responsible for the voltage build up in the primary windings of the coil. In the CDI system
the parts include the exciter coil, the trigger coil, the wires from stator plate to CDI box and to the low resistance primary
windings in the ignition coil.
Primary Clutch: Drive clutch on engine.
Primary Compression: Pressure built up in the crankcase of a two stroke engine.
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