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Specifications
Bore
φ
32.0mm
Stroke
26.0mm
Stroke volume
20.9cc
Weight (approx.)
Main body : 690g / Muffler : 83g / Ignition system : 113g / Engine mount set : 156g
Practical Speed
Approx. 2,000-9,500rpm
Applications
4-stroke 100~110class
Propeller
15”×8” ~ 16”×8”
Static thrust
Approx. 3-4kgf
Fuel
Regular gasoline : Oil (2-stroke oil) =20:1 (Volume ratio)
Fuel consumption
Approx 15cc/min (At full throttle, approx 8,800rpm)
*Fuel flow varies depends upon prop load. More fuel flow with larger load and less fuel flow with smaller load.
Battery for ignition system
Voltage:6-8V higher than 1,000mA is recommended
Accessories
Instructions for SAITO
FG-21(AAC) 4-Stroke Gasoline Single Engine
Thanks for buying SAITO FG-21 4-stroke gasoline engine
exclusively for model airplanes.
In order to avoid misuse, please be sure to read well the instructions
carefully. If there should be any deficiency, inconvenience, etc.
concerning the manufacture, our company will repair them with responsibility.
Any failure or trouble caused by unnecessary disassembly, modification, or other
uses than those provided in the instruction manuals is not subject to the warranty,
however.
Moreover, all responsibilities for the use of the engine, and other obligations and
responsibilities based on laws, regulations, etc. are borne by the purchaser and the
user, and SAITO SEISAKUSHO CO., LTD. is exempt from any responsibilities.
SAITO FG-21 is a 4-stroke gasoline engine exclusively for model airplanes which
is designed with emphasis on high performance, durability, and weight saving.
This engine is modified based on existing FG-20 gasoline engine, equipped with
renewed ignition system. For the airplane on which FA-125 is installed, FG-21 can
be replaced easily with minimal change such as fuel tank and lines to gasoline-
resistant ones.
Features of FG-21
Cylinder
The cylinder head is integrated with the cylinder in order to prevent distortion, save weight and improve
cooling effectiveness. Hard chromium is plated the cylinder without using liners for higher durability.
Piston
High-silicon-containing aluminum piston equipped with compression ring for higher performance.
Connecting rod
Robust with forged high-strength aluminum. As a measure for gasoline engine, phosphor bronze busing is
pressed into the big end to improve heat resistance.
Crankshaft
Robust with forged chromium molybdenum steel and supported by two ball bearings.
Cam gear
Placed in the front for compactification.
Cam
High output type, high cam specification.
Combustion chamber Volumetric efficiency and combustion efficiency are improved by adoption of a vent roof type combustion
chamber.
Propeller nut
Designed to have double nuts preventing loosening and fall-off for safety.
Exhaust sound
Sound quality similar to the exhaust sound of the real airplane. And as calm as a glow engine.
Carburetor
Self-designed and developed carburetor with a pump for small-seize 4-stroke gasoline engines.
Ignition system
A new designed battery type electronic ignition and the electronic spark advancing system.
Starting method
Forward rotation (CCW) can be manually started due to automatic spark advancing system. (Using a starter
is still recommended for safety)
Fuel
With the same composite fuel as two cycle gasoline engine which contains 5% of oil content.
Flight pattern
Since there are no worries about the inclination of oil, all acrobatic flights are possible.
Spark plug
Small-size spark plug dedicated for our 4-stroke engine, of which screw size is the same as that of glow plug
(UNEF1/4-32)
Features of the gasoline engine
・
Fuel efficient.
・
Low cost of fuel.
・
Easy to install “smoke system” (by using muffler pressure or crank pressure)
・
The airframe could not be soiled easily.
1.
Limit gauge (0.1t) for tappet adjustment
1 pc.
2.
Spanner for tappet adjusting lock nut
1 pc.
3.
Hexagonal wrench set
1 set
4.
Ignition system (with sensor attached)
1 pc.
5.
Spark plug [SAITO SP-1] (attached)
1 pc.
6.
Plug wrench
1 pc.
7.
Muffler complete
1 set
8.
Engine mount set
1 set