I got a bunch more flying on the Yak over the past couple of days. I will first say I really am enjoying this plane, but I am hating the GP61 motor. It has a mid range burble that can not be cured by any form of tuning. If you lean the bottom it will minimize it ever so slightly, but then the little motor will not start with any amount of flipping. If you try to lean the high end, it will start to minimize the top end with no difference in the burble. I have tried five different carbs, four different ignitions, 4 different props, 4 different hall sensors, and a variety of other remedies with no positive results to report.
I am pretty shocked as most folks in the know claim this motor runs like a scalded dog in altitudes under 3500 feet. Well I live at 5900 ASL and this motor has such a bad mid range burble it makes it horrendous to fly. Now I get told that a Walbro WT805 carb is the ticket. You have got to be kidding me. I have spent the better part of five months messing with this motor on two different airframes.
Well I took the POS GP61 off the plane last night and attached my only other spare motor I had in the arsenal which was an EME60. With less than five minutes tuning I had it spinning the Falcon 24X8 prop at 6700 rpm. The motor is almost brand new and has less than 20 ounces of fuel ran threw it. I ran six tanks of fuel threw her today and I am very happy. It runs with no annoying mid range burble. It has plenty of power for the plane. I will say it has a tad less than the GP but it tuned in half the time and sounds like a good two stroke motor should.
The plane now has around 25 flights and I really love this plane. I will say it may be my favorite of any plane that I have owned since I started flying. I have had a bunch of planes over the last couple of years, so I believe this statement says volumes about the plane. I will tell you Donnie @Flying Skunks from Chief Aircraft really spoke volumes about this plane and I was a bit skeptical. Gosh was I wrong. I think this plane is one of the most underrated planes around.
The plane has been thrown into IMAC and today the plane got some hovering, high alpha stuff, and some other basic 3D stuff. It preformed beautifully even though I have it set up with only 35 degrees of elevator throw and 35 degrees of aileron as this plane is primarily set up for IMAC. With those numbers it performed flawlessly. I removed a piece of lead that was lying on batteries as the EME was much lighter than the GP. It flies completely neutral with hands off inverted with no drop.
The only change I have in store for the plane is to replace the servos in this beast to the new SAVOX SB2282SG's. I have been testing them for the manufacturer for sometime and now they will find a new home in this plane as its definitely worthy of a servo of this caliber. These servos have been bullet proof during testing. They are a bit pricey, but I will test them to see how much difference I can feel. I currently have 1268SG on all surfaces and a 1270TG on the rudder. The throttle is a 1267SG. These servos will taken from a well flown Aeroworks Yak55 that I no longer own. The servos were well used and are in near perfect condition with almost no slop in the gear train.