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ORIGINAL: aussiesteve

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ORIGINAL: ahicks
As it is, I'll not likely ever wear one of these out using any decent oil designed for use in air cooled engines.

Give the man a prize for the most commonsense comment as it is 100% true.

The below information applies to just about any engine we use in theis hobby.

For your break in, The trick is to heat cycle the flame plated chrome liner to consolidate it and to flush out the excessive metallic particles that are created in those first few runs. This is most easily done by putting that engine in the air and flying it and using a slightly richer oil mix than normal (30:1 instead of 40:1). The rings on these (and 99.9% or all other Chinese engines) are quite hard so they will never really conform to the bore anyway (how often do you see a comment about people noting the rings look "just like new" after a while of running).

Ever bought a new chainsaw? How was that run in? (They start them, then tune them then run them hard)

Ever read the piston ring manufacturers instruction on how to break in piston rings? (they tell you to apply reasonable load as early as possible).

The best way to run these 2 strokes in is to give them a little more oil than normal for the first couple of litres of fuel, the make them work. You want to get the cylinder BMEP high enough to make that piston ring work and you are not going to do that by "babying" it. That applies to about 99% or all ringed internal combustion engines on the planet. Defintiely avoid prolonged WOT runs for the first hour or so but do not be afraid to give the engine some work. Also avoid long periods of low cooling air flow (such as extended hovering or long ground runs without the plane moving). Do not run it rich on the fuel settings, (do not run it lean either) Just use it how it is intended to be used.

For the break in period (The first hour or two of running), You need an oil that will flush out the metal particles. For this reason it is always a good idea to use a reasonably rich oil ratio. Many use Pennzoil air cooled at 30:1 but your location may not have that. I use the oil I will be using in the engine for it's lifetime and instead of mixing it at 40:1 (which is my normal mix), I mix it at 30:1 for the first couple of litres.

As to which oil to use? there are many good ones available. If you can get Stihl Ultra HP, use that at 30:1 for break in of the first couple of litres and at 40:1 or 50:1 for the rest of the engines life. If you can get Mobil 2T Racing - same comment, also Redline Racing or "Kart" oil - same ratios. Castrol TTS is another choice as is Motul 800. If you can't find any of those readily where you live, go to your local morocycle shop and ask what they stock for air cooled dirt bikes and use that. If there isn't a bike shop near you, try your local chainsaw / garden equipment shop.

Start the engine, let it warm up for a few seconds, tune the high needle to max RPM then richen it about 1/8 turn, set the low needle to give a good crisp transition then go fly it. Running a tank on the ground ususally ends up doing more harm than good as most enignes get overheated when doing that. Very few provide proper cooling in that process.

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ORIGINAL: WildeOne

What's real clear to me is that RCGF needs to clean up their business practices, such as serializing all complete engines to provide traceability, etc., etc., etc. I have several 20 CC motors that have run perfectly right out of the box. Plus a couple of others not run yet. This crap about sn or no sn for support is just that, although I have no plans to do that either. I know how and have the parts to fix the Walbro (sort of) carbs on these motors, which is the most common problem area. You'd think that RCGF would have learned by now!

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ORIGINAL: sailr

I bought a 20cc rcgf and it's been around the shop a while. I installed it on an airplane and somehow the muffler has disappeared!! Dang! The airplane is ready to go except for a muffler. The cost for replacement mufflers for the rcgf engines is a bit outragious! $30 for a 20cc single stack muffler and $68 for a pitts style?

Anybody know where I can find a better deal than that? Anybody that upgraded to the pitts want to sell the stock muffler?

HELP!

Grounded in Florida!

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ORIGINAL: capnduane

sailr, Himodel.com has the stock muffler for the rcgf 20 for $16.64. Part # P20-14. I got a pitts muffler for the 20, from them a few months ago for $28, but didn't see it on their web site. Might have missed it, check them out. Duane

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ORIGINAL: raydar

Just a heads up that the stock muffler is 3 oz and the himodels pitts muffler is heavier by another couple oz AND you loose a few hundered rpm with it, it is a good price though and quietens the engine down nicely.