Trent, I just picked up an MVVS .26 brand new. Haven't tried running it yet. I did see a post that said it was designed for low or no nitro, so got some 5% and will add castor.

Are you sure it's broken in, i.e., holds a just-lean setting without overheating? If not, no point messing with idle till it will. Are you familiar with pinch tests for adjusting high and low needle? Did that fail to work?

I suspect you won't find much direct experience with this engine, but there is a dealer or former dealer who frequents the Glow Engine forum, Dar Zeelon, who might be helpful. I'm going to follow along on this since I may need help myself!

Jim