Steve

No need to worry. The Zama carb will work just fine. I have one that worked OK, but I choose to buy a walbro wt-433($20.00 US) from Peter at wackerengines. It is a little larger carb and feeds the a engine little more fuel and air. And that means more power and RPM,s. With the wt-433 carb and the OPTI-2 oil I am getting 7400 RPM out of my old Ryobi 31cc with a MAS 18x8 prop. I fly around most of the time at half throttle. It will not hover, but I can hold her there for a few seconds before she starts to fall back. When that happens I just give here full throttle and watch her climb.