Scorpa 2008 SY-250FR 15thA, Manual Manual

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The richness of the air-fuel mixture with the throttle open ¼ or less can be set by adjusting the pilot jet.
Jet needle groove position adjustment
Adjusting the jet needle position affects the acceleration when the throttle is 1/8 to ¾ open.
Too rich at intermediate speeds
Rough engine operation is felt and the engine will not pick up speed smoothly. In this case, step up the
jet needle clip by one groove and move down the needle to lean out the mixture.
Too lean at intermediate speeds
The engine breathes hard and will net pick up speed quickly.
Step down the jet needle clip by one groove and move up the needle to enrich the mixture.
Jet needle adjustment
The needle is adjusted by changing it.
The tapered sections of all jet needles have the same starting positions, but the needles are available
with different straight-portion diameters.
Carburettor pump adjustment
The carburettor pump actuator must begin to turn when the valve begin to go up. You can verify this
while actuating gas handle.
If not, adjust the cable tension in order to valve upping and pump turning begin in the same time.
6.7 Play of the valves
As the time goes along, the play of the valves changes and it may alter the ratio of air to fuel of the inlet
air-fuel mixture.
The solution is so to make it adjust by your dealer, as often as written in „List of the regular
maintenance and lubrications‟.
It is a really complicated operation, which requires a professional expertise.
6.8 Wheel-axle units
6.8.1 Front wheel removal
1. Loosen the screws on the bottom of the front fork arm (brake disc side) and loosen the screw
of the front wheel-axle.
2. Loosen the screws that were left of the front fork arm (opposite side of brake disc).
2. Lift the front wheel, by using a raising stand or by putting a jack under the engine protection.
Take care the bike is stalled enough to prevent it from overturning.
3. Remove successively the axle and the wheel.