ENGINE TUNING GUIDE
HIGH-SPEED NEEDLE
IDLE STOP SCREW
The "idle stop" screw is located on the backside of the carburetor.This increases or
decreases the idle speed without changing the fuel mixture.The barrel should be a-
-pproximately 1mm from fully closed.
IDLE STOP
SCREW
HIGH-SPEED
NEEDLE
04
RUNNING THE ENGINE
i) STARTING THE ENGINE
IMPORTANT!Your radio system must ALWAYS be turned on and the transmitterantenna
fully extended when running the engine!
Press gently the button ( on the radio diagram) to start the engine and fill the fuel tank at
the same time.
8
1.Please pull out the transmitter antenna and then turn on the power switch first,before
turning on the receiver.
2.Please raises the tires off the ground and check if the control is responding.
3.Hold the throttle trigger to let the truck run. If it doesn't work, please adjust the throttle
servo and trim.
4.Please replace the battery,when the speed drops down.
5.When you finish the racing,please turn the receiver switch off first, then the transmitter
switch.
6.Please make sure the battery is disconnectted and remove the battery after finishing the
racing.
The "high-speed" needle is sticking up from the carburetor.This controls the fuel to air
mixture of the carburetor.The needle is pre-set for break-in from the factory at 2-1/2 t-
-urns out from fully closed.Once the engine is broken-in,the high-speed needle would
typically run from 2 to 2-1/2 turns out from closed,depending on the weather,humidity
and altitude above sea level.To richen the mixture turn the needle counterclockwise.To
lean it,turn the needle clockwise.
LOW-SPEED NEEDLE
The"low-speed" needle is the screw in the carb body opposite the throttle arm. it controls
the fuel to air mixture at low throttle settings.There is a simple way of adjusting the low
-speed needle correctly called the "pinch test."With the engine at idle,pinch the fuel line
and listen how the engine speeds up or slows down. If the engine increases its speed for
about 2 or 3 seconds and then loses speed, the needle is set correctly. If the engine loses
RPM quickly,it is set too lean and the lowspeed needle needs to be opened
(counterclockwise) to richen the mixture. Pinch again to check the mixture.If the engine
takes longer than 4 seconds to slow down, lean (clockwise) the low-speed needleand then
pinch again to check the mixture.
IMPORTANT! To insure long life and good performance from your engine,you MUST break-in the engine.
The break-in period is critical for long life of the internal parts of the engine.This should be done over the
first 5 tanks of fuel
.
LOW-SPEED
NEEDLE
RC OPERATING PROCEDURES
Summary of Contents for BS805T
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