Instruction manual
11
Telemetry
Telemetry is a huge asset to help you tune your 
engine. The ignition module is even capable 
of communicating with Spektrum telemetry 
systems directly so you won’t have to add 
an additional RPM sensor. You will need to 
connect the Evolution Ignition Telemetry 
Adapter (EVOA107) between the RPM port on 
the ignition unit and the RPM port on your 
Spektrum telemetry module in order to utilize 
this feature. Telemetry systems other than 
Spektrum may require a dedicated RPM sensor. 
We recommend using the Spektrum DSMX
®
 Full 
Range Aircraft Telemetry Module (SPM9548) 
in conjunction with the included adapter. This 
system allows you to see real-time RPM and 
temperature readings from the engine.
The temperature sensor should be wrapped 
around the base of the spark plug on the 
cylinder head. Using telemetry gives you an 
accurate representation of actual temperature 
and rpm figures during use, and warnings can 
be set to go off if your engine is getting too hot.
The temperature range can be 230–250°F 
on average. Set your maximum temperature 
warning to go off if the engine exceeds 280°F. 
If your engine is continually near this peak 
temperature or higher, immediately decrease 
throttle to bring the temperature down. If this 
continues to occur, land the airplane and add 
additional baffling to your cowl. It is not good 
for the engine to run at temperatures this high 
and could cause damage if not attended to.
Starting and Operating the 20GX2 Engine
Now that you have the baseline needle 
valve settings, you are ready to start your 
engine for the first time. With the 20GX2 it is 
very important to allow the temperature to 
stabilize above 170°F (75°C) before making 
any adjustments; adjusting prior to the engine 
warming up will lead you to inaccurate settings. 
As the engine warms up you will notice the 
rpms naturally rising.
If you do not have a temp gun or have sensors 
installed on your engine, allow the engine 
to run at half throttle for at least 45 seconds 
before attempting to set the high-speed 
needle. If you have accurately set the low-
speed needle as described you should not 
need to adjust it.
Priming
1.  Make sure your ignition is off. 
2. Open the throttle fully, hold a finger over 
the carburetor intake and flip the propeller 
6 times.
3. Remove your finger from the carburetor and 
flip the engine another 6 times.
4. Close the carburetor completely with your 
throttle stick and then open it two detents 
from closed. This will allow the engine to 
start at a high throttle setting.
Because each fuel system and installation is 
slightly different, you may find the need to 
modify the above procedure for your individual 
setup. The above procedure should work for 
most installations.
Starting and Running the Engine
Until the engine is broken in, use an electric 
starter to start the engine. Once it is fully 
broken in it can be started by hand, but it is 
easier and safer to start the engine with an 
electric starter.
1.  Turn on the ignition.
2. Rotate the propeller in a backwards 
direction against compression.
3. Push the starter firmly against the nose 
cone and engage. The engine should start 
relatively quickly, within 1–2 seconds. Once 
the engine starts disengage the starter.
4. Let the engine run at mid-throttle for 45 
seconds to stabilize the temperatures.
a.  If the engine doesn’t start quickly, 
disengage the starter. Continuously 
running the starter can flood the engine.
b.  Check to ensure the fuel is moving 
through the carburetor system.
c.   If the engine appears not to have any fuel, 
repeat the priming procedure above.
d.  Repeat 1–4 of Starting and Running the 
Engine.










