TM RACING 2012 TM 100 MX, Руководство пользователя и по обслуживанию

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FRAME AND ENGINE MAINTENANCE FRAME AND ENGINE MAINTENANCE
CARBURETOR ADJUSTMENTS
OPERATION AT IDLING SPEED
Turn the idle adjustment screw to gently adjust engine range – clockwise
to increase, anticlockwise to decrease. Make sure the engine speed is
as smooth and constant as possible.
OPERATION WITH THROTTLE VALVE OPENING
If you have properly regulated the idling speed and partial capacity but
the engine rumbles, emits excessive fumes and reaches full speed
brusquely revving faster than expected, it could be a too rich mixture or
a too high fuel level in the float bowl
OPERATION WITH THROTTLE VALVE PARTIALLY OPEN (PARTIAL
CAPACITY)
If the engine runs on a four-stroke cycle or with decreased power during
acceleration with the throttle valve partially open, then you will need to
lower the jet needle raising the clip by 1 groove.
If instead the engine rattles, especially during acceleration and at high
speeds, then you will need to raise the jet needle.
Alternatively, if you encounter similar problems while travelling at low
speed and at partial capacity, you need to check whether the engine
has flooded and set a leaner mixture, or set a richer one if the engine
is rattling.
OPERATION WITH THROTTLE FULLY OPEN (MAX CAPACITY)
If after a while at full gas the insulating part of a new plug (the ceramic
part around the electrodes) appears particularly bright or white, you will
need to replace the main jet with a richer one.
If instead the insulating part of the plug appears dark or blackened, you
will need to replace the main jet with a leaner one.
Contact your TM agent for selecting needles, main and idle jets or any
other part of the carburetor.
CHECK FUEL LEVEL
(FLOAT HEIGHT) (A)
Disassemble the carburetor and remove the float bowl. Turn the carbure -
tor upside-down and keep it inclined so that the float rests on the needle
valve but does not compress the spring with its weight.
In this position, use a gauge to measure the distance between the apex
of the float body and the float bowl surface on the carburetor body (see
image).
Refer to the technical data for the correct value for your motorcycle.
If necessary, adjust the height by slightly bending the float adjustment
plate (1).
If possible, also check the tightness and the state of wear of the needle
valve cone: if in doubt replace the valve and brass seat.
Mount the float bowl, mount the carburetor and adjust the idle speed.
BASIC INDICATIONS REGARDING CARBURETOR
WEAR
The throttle valve, jet needle and the float needle valve are subject to
great wear caused by engine vibration. As a consequence the carbure -
tor may malfunction (e.g. enrichening of the mixture). These parts must
therefore be controlled after 100 hours.
POSITIONS OF NEEDLE CLIP FROM TOP