With the engine selected and the proper
linkage configuration, you can begin the break-in process. Recently, I purchased a 29%-scale
Bücker Bü 133 that was scaled down from Gary
Allen plans and built by Raymond Schmidt Jr.
This is a unique model that features a Moki 210
for power. On a glow engine like the Moki, a
rather large opening would be required in the
cowl to allow access to the needle valve. For the
Bü 133, I made a small (2mm) opening to access
the high-speed needle, which I modified with a
socket insert secured to the high-speed needle
using JB Weld epoxy. I can now adjust the high-
speed valve by simply inserting a socket head
driver into the needle valve.
For the initial setup, I prefer to begin with
the high-end needle and idle disc at the
factory-recommended settings. Always check
the needle adjustments as some engines
are shipped with both needles in the closed
position. After the engine starts, I generally
Servos used to operate the choke and throttle arms eliminate the need for you to
access the carburetor, resulting in the ability to add scale features to the cowl of
To direct airflow directly to the cylinder(s), make baffles out of wood, fiberglass,
or aluminum. Proper cooling techniques are critical—especially on inline twin
engines—to ensure that the rear cylinder is at the proper temperature.
To conceal certain areas of
the engine, you may need to
install the engine at a slight
angle while ensuring that
the shaft is in the correct
position, as it is here on
this AT- 6.