I've been using it at 50:1 in all my lawn equipment for years. I used it at 32:1 in my G26 Zenoah for about 2 years and at 16:1 in my G51 SuperTigre for about 30 hours. Both engines looked VERY good on tear down after using the Pennzoil. I have since switched to using Redline Racing Two Stroke oil in my plane engines and I am still mixing at the same ratio in all of my engines which now include a Saito 91 running on the same 32:1 mix as the Zenoah. (The lawn equipment is still on Pennz) I have had ZERO engine problems on any of my equipment, lawn or aviation, while using either of the these fine oils. Pennz and Redline are two of the cleanest running oils I have experienced.