ORIGINAL: av8tor1977
But running them rich does do a very nice job of carboning them up. Glow engines don't carbon up much due to the type of fuel and the combustion temps. They sometimes get varnished up, but that's a different issue usually caused by castor oil. Gas engines burn much hotter, and a rich mixture will carbon one up fairly quickly.
AV8TOR
On the bold, I'm sorry, that's a stretch for me. Not if you're running a quality oil. That may be true on a lawn mower or a leaf blower running garbage oil, but an engine running on the rich side that's making enough power to fly, carboning up to the point even sport flying performance is affected by it? That would be something I'd have to see to believe.