Woke up early today and went to a private field to fly my radikal and ended up putting an entire gallon through it!!! For all you guys and gals out there that are new to gassers (myself included)I have found a few things that might be helpful. I'm sure there are a lot of veteran gassers out there that are going to read this and say "DUH NO KIDDING" but maybe this will help someone else.
I'm not going to go through the whole break-in process because all I did was exactly what was posted on the Radikal FYI post. You can also go to http://www.insideheli.com
as well. Sparks has done a excellent write up on this machine and how to tune it.
So what do I have to offer thats new on this topic?? NOTHING!
These are just a few observations that I have made during my time with this engine and airframe.
First. Do you need an aluminum insulator block for the carb? No you don't, but do yourself a favor and get one. I fooled with the stock one a few times with some success, but since I installed the aluminum one I never touched it again.
Second. Do you need an air filter? YES you do. Will it work without it? Yes it will. Helicopters are basically lawnmowers without decks and we all know how much dirt,grass,and crap they stir up. Besides the air filter will make tuning a little easier as well.
Third. We all know that no two anythings are the same, especially engines. However after fooling with a few of these STOCK G20's I can say that the recommended needle settings will get you very close to where you need to be for a reliable running engine.
Fourth. When you do make a needle adjustment, high or low, make sure your engine is up to operating temp. And MOST IMPORTANTLY make very very minute adjustments and I mean the width or even sometimes half the width of the screwdriver blade! It is very easy to go right by the "sweet spot" if you go to fast. Check your high speed progress with good hard climb outs and let em climb for a good bit, a short 20 foot blast doesn't tell you much.
Fifth. This engine has a little miss or "four stroke" when it is not loaded (such as hovering) DO NOT TRY TO TUNE THIS OUT!!! It is a characteristic of this particular engine that will diminish significantly as the motor breaks in. Remember this is not a nitro engine some of these engines will still be breaking in with 4 or 5 gallons through them. If your low is properly tuned you will get a little miss or "four stroke" every 4 or 5 seconds.
IF YOU TUNE THIS OUT, YOUR LOW END WILL BE TO LEAN AND YOU
WILL BURN THE ENGINE UP IF YOU CONTINUE TO RUN IT THIS WAY!
Sixth. Get the recommended blades(620 wide chords) you pick the manufacturer. You won't believe the difference they make.
Seventh. Reduce the pitch!!! I know I know..... everyone wants plus or minus 15 degrees!! Don't do it. This machine puts out a ton of thrust at plus or minus 10 degrees. Don't forget this is not a nitro, they make power very differently! Put the right blades on and reduce you pitch. Trust me you will like it!
Eighth. We all know there was a blade grip warning and I'm not going get into all that because it has already been addressed, so once you have your new grips installed and your favorite carbon fiber blades on, your gonna want to run at least 1900-1950 head speed with the 6.4 gear ratio. This will ensure that you keep the engine in its powerband. A lot of folks think that this engine is down on power because they're running it at 1750-1850. Next time your at a stop light, put your car in third gear and dump the clutch, that is basically what your doing if you lug this engine down. 1750-1850 is fine for scale flying but if you want it to boogie, you gotta turn up the music!
Ninth. Your oil mix, for break in you want a petroleum based ashless two-stroke oil such as Lawn boy after that a good quality synthetic oil will do the trick. 32:1 is a good ratio. But check the oil manufacturers recommendations on the mix ratio.
Thats what I have for now and like I said..... Nothing new just my experiences.
Oh yeah and HAVE FUN!!!!!!!!!