Hi-Speed Adjustment
After initial acceleration the engine should pull at a steady rate while maintaining a two-stroke whine and a noticeable
trail of smoke. If the engine labors and is sluggish with heavy smoke, the mixture is too rich and needs to be leaned by
turning the Hi-Speed needle clockwise in one hour increments until it runs smooth. If the engine is not smoking, it is
too lean and you must richen the mixture by turning the needle counter-clockwise. Don't be confused by the sound of
the engine and the actual performance. A leaner mixture will produce a higher pitch exhaust note but this does not
necessarily mean improved performance as the engine is on the verge of over heating and possible damage. Ideally
you want to run the engine so that it is on the slightly rich side of optimum. This will give you the best combination of
speed and engine life.
CAUTION:
The engine is too lean and overheating if it accelerates rapidly with a high pitch
scream then seems to labor, stop smoking, or loses speed. This can be caused by the terrain, atmospheric conditions,
or drastic altitude changes. To avoid permanent engine damage, Immediately richen the mixture by turning the Hi-
Speed needle counter-clockwise at least "two hours" and be prepared for further adjustments before running again.
About Glow Plugs
The glow plug is like the ignition system in your automobile. The coiled element in the center of the plug glows red hot
when connected to a Glow Igniter. This is what ignites the fuel/air mixture when compressed in the cylinder. When the
engine fires the heat generated from the burning fuel/air mixture keeps the element hot. Common reasons for the
engine not starting are the Glow Igniter failing, glow plug wet with fuel, or damaged glow plug element. Use a spare
glow plug to check the igniter battery. If the igniter lights the spare glow plug, remove the plug from the engine to check
it in the same manner. A wet glow plug means there is excessive fuel in the engine; commonly called "flooding". To
eliminate this put a rag over the head and turn the engine over a few seconds with your "Spin-Start". Install the glow
plug making sure you have the brass gasket on it. The engine should start now.
Testing the Temperature
The ideal operating temperature for the engine will vary with the air temperature but in general it should be in the 200 to
230 degree Fahrenheit range. A simple way to check the engine temperature is to put a few drops of water on the top
of the head/heatsink. It should take 3-5 seconds for the water to evaporate. If it boils away quickly the engine is
overheating and the Hi-Speed needle must be richened (turned counter-clockwise) at least "two hours". If you plan on
racing or prolonged hi-speed running, there are several inexpensive hand held digital temperature gauges available you
may want to invest in.
About the Transmitter
1. Power Switch - Turns the Transmitter ON and OFF.
2. Steering Wheel - Controls the steering.
3. Steering Trim Tab - Fine tunes the steering neutral position.
4. Throttle Trigger - Pull back for throttle and push forward for brakes.
5. Throttle Trim Tab - Fine tunes the Idle/Brakes.
6. Transmitter Display - Digital readout shows battery voltage and feature functions/settings.
7. Transmitter Antenna - Transmits signal to the receiver.
The JR radio installed in the Muggy is a professional level system with many more
features compared to radios contained in other RTR vehicles.. Be sure to read through
the Transmitter manual included for complete instructions on what and how to use these
features. The following is a simple guide to commonly used and referred to items needed
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