What is a desirable temperature range for 2cycle engines. I realize the cooler the better but at what temp does baffling become an issue. Ive ordered an infrared thermometer and Im wondering what readings others are getting. Thanks for your replys

About 220 deg F. for glow

Higher for gassers, depending on how much oil you want to use. A very leaned set G-23 with lots of oil in the fuel (32:1) can get up to 325 deg F

Just my experiences with helicopter.

My gasser runs about 209 degrees F. That temp was taken off the head, just after landing from a 15 minute flight. My understanding is most people with gassers like to stay under 200 if possible. Anywhere from 165 to 180. An ABC glow motor needs to be warm. They should be running about 350 degrees F. at the head when tuned properly. Any cooler and the liner can pinch the crown of the piston, robbing power in the long run. Ringed glow motors can run much cooler since there's no pinch at TDC to worry about.

Just got a 3W100 and they told me to keep it under 200 degrees.

Temp readings are highly variable depending on the method used. Try it two ways and see what I mean. After a flight, take a reading with the engine idling - aim at a spot on the cylinder between the fins. Shut the engine off and keep taking readings from the same spot. When I shut my 3W-100 off, it reads about 210F.

The cylinder on my ZDZ-80 reads about 250F at full throttle on the test stand.

Bottom line, you need to know where and how the readings are taken to compare temps.

3W told me it should be 200 at idling by useing temp gun and shooting thur prop.