I am having trouble understanding why you wouldn't want to run 5% in your bigger engine. It's cheaper, which will make a difference in the long run. 5% will run just fine in glow engines made for the American market too (OS, Saito, etc). You may notice the idle won't go quite as low, and you may notice a small decrease in power. For racing or aerobatics that might be an issue, but otherwise it's nothing to worry about.
Last edited by jester_s1; 05-16-2018 at 05:04 AM.