Dave,

Just an FYI. I pulled the regulator apart (learned how in another thread here) and found it sticking. I was able to work it loose and did 3 flights with it last night. It's now set about 1 1/4 turns open instead of being comletely closed with great transition and absolutely no more loading up. 2 Flights were on 30% and the last was on 20% and other than a slight power difference between the fuels no problems at all.

I will say this, this engine pulls my Cap580 40 size using a 13X6 APC with gobs of authority, takeoffs are around 1/3 to 1/2 throttle and full power climbs are just like the energizer bunny, they just keep going and going and going.

It now runs as I have come to expect from all of my YS engines

I do have just one other question. Would a 12X6 3-Blade prop work with this engine. If not what size do you recommend and which brand? I'm not worried about losing some thrust as I have plenty. I'm after looks