Mark,

Wasn't trying to beat you up at all. Just passing on what I've experienced with a lot of engines. The older carbs can take a beating if they didn't have the later ethanol resistant gaskets and diaphrams in them but I've not encountered any issues with gas remaining inside two stroke gas R/C engines that have sat for several years. Oil content in the fuel does make a difference in how long they can sit. More oil = longer storage times. Right now I'm surrounded by about 50 of them and none of them exhibit any ill effects of extended storage without flushing. You should not experience any problems at all if leaving gas in the plane's tank for a couple of weeks.