Engine Tuning; Carburetor Factory Settings; Adjusting The High Speed Needle; Adjusting The Low Speed Needle - ProBoat Rockstar 48 Owner's Manual

EN

Engine Tuning

Before making adjustments:
• Ensure there are no leaks or obstructions in the fuel
tank, fuel tubing or the carburetor. Any faults can affect
engine operation and tuning.
• The carburetor needle is very sensitive. Adjusting the
needle even 1/16 of a turn is a significant change. Be
careful when making adjustments.

Carburetor Factory Settings

The engine can be tuned from the factory settings to
optimize performance under various conditions. If you
lose track of the engine settings, return to these factory
carburetor settings.

Adjusting the High Speed Needle

If the top speed is slow, turn in the high-speed needle
1/16 turn and test. Do not exceed 1/4 turn in from factory
setting (minimum 1 1/4 turn out from closed) or the
engine will be damaged.

Adjusting the Low Speed Needle

If the vehicle accelerates slowly, turn in the low-speed
needle 1/16 turn and test.
Do not exceed 1/4 turn in from the factory setting
(minimum 1 turn out from closed) or the engine will be
damaged.

Idle Adjustment

RPM Lower (Arrow to left)
RPM Higher (Arrow to right)
If the idle is set too high (propeller turns) or too low
(engine does not stay running), adjust the idle speed on
the carburetor.
12
High-Speed Needle (on
the left side). Close the
high-speed needle by
turning it clockwise until
it stops, then turn it
counterclockwise 1 1/2
turns out (open).
Idle Screw (below the needles).
Center the screw so the slot is
straight up and down.
Low-Speed Needle
(on the right side).
Close the low-speed
needle by turning
it clockwise until it
stops, then turn it
counterclockwise 1
1/4 turns out (open).
1/16
Max 1/4
1/16
Max 1/4
RPM RPM
Lower Higher
RockStar 48