KTM EXC User Manual

Repair manual KTM 250 / 300 / 380 Art No 3206004 -E
Checking the voltage regulator-rectifier (Shindengen)
– Start the engine and switch on the low beam.
– Connect a voltmeter to the two terminals of the capacitor (red/white
cable = positive, brown cable = negative).
– Accelerate the engine to a speed of 5000 r.p.m. and read off the
voltage.
Nominal value: 14.0 – 15.0 V
In the case of a significant deviation from the nominal value:
– Check the capacitor
– Check the connector between the stator and the voltage regulator-
rectifier and the connector between the voltage regulator-rectifier and
the cable tree.
– Check the stator.
– Replace the voltage regulator-rectifier.
Checking the voltage regulator (Kokusan)
A defect voltage regulator can cause different kinds of trouble:
● No voltage in the circuit
In this case, the voltage regulator must be disconnected at idle speed.
The voltage regulator is defect if the power consumers now work
properly.
If the power consumers are still not supplied with power, the switch,
the wiring harness or the ignition system must be checked for defects.
● Excessive voltage in the circuit
The bulbs burn out. In this case the voltage regulator must be
replaced.
Checking the voltage regulator (Tympanium)
NOTE: The voltage regulators are connected downstream of the
switches. One of the voltage regulators regulates only the brake light
circuit, the other regulates the circuit for the head light, the tail light, the
speedometer illumination and the horn.
A defect voltage regulator can cause different kinds of trouble:
● No voltage in the circuit
In this case, the voltage regulator must be disconnected at idle speed.
The voltage regulator is defect if the power consumers now work
properly.
If the power consumers are still not supplied with power, the switch,
the wiring harness or the ignition system must be checked for defects.
● Excessive voltage in the circuit
The bulbs burn out.
Connect a voltmeter (yellow cable = positive, brown cable = negative)
to check the voltage. Start the engine and switch on the power
consumers.
At an engine speed of 3000 r.p.m, the voltage regulator must supply a
voltage of 12.0 - 14.0 V A.C. At higher engine speeds, the limit of 14.0
V should not be exceeded either.
If the reading significantly deviates from the nominal value, replace the
voltage regulator.
7-2C

KTM EXC Specifications

General

Ignition	Kokusan
Starter	Kickstarter
Transmission	6-speed
Engine Type	Single Cylinder, 2-Stroke
Cooling	Liquid Cooled
Lubrication	Premix