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Old 04-07-2004, 08:00 PM   #7921
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Originally posted by rodrigo1508
Well in my break in proses I have just gone through 2-3 tanks idle at 2 mins cycles because it was too tight and I have now gone through 5 -6 tanks of InitialD WOT style, do I need more or can start to run and lean?
What engine are you breaking in? With the newer engines like Nova, you may need more tanks.

You will know when you completed break in process when you take the engine heatsink off and check the inside of the piston liner. It should be polished. When you turn the flywheel, you can see that the piston can reach to the top of the sleeve with a little bit of resistance. If it's still stuck half way and you cannot turn the flywheel to crank it when the heatsink is off, the engine is still not fully broken in yet.
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Old 04-07-2004, 08:01 PM   #7922
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Originally posted by AMGRacer
Another option is the new Futaba RX battery checker. But it does not do the glowstarter.
oh, that is one awesome battery checker !! i like it very much !
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Old 04-07-2004, 08:02 PM   #7923
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Default Re: Josh Cyrul's servo of choice

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Originally posted by PSI Racing
Hey D,
Here is Josh Cyrul's response to the servo question.
Cool. I guess one man's meat another man's poison ! Perhaps his hands and reflexes are fast enough to compensate for the 0.05 seconds ! Mere mortal drivers like myself would need to get every speed advantage.
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Old 04-07-2004, 08:03 PM   #7924
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Originally posted by B
Nah, that would be not a good investment. When the batt stars to fade, take the car in, and just run the batts so that the servo cannot turn any more, that would be a sufficient discharge process.
True and I agree with you but wouldn't running till the servos cannot turn anymore be dangerous?
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Old 04-07-2004, 08:25 PM   #7925
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Originally posted by InitialD
What engine are you breaking in? With the newer engines like Nova, you may need more tanks.

You will know when you completed break in process when you take the engine heatsink off and check the inside of the piston liner. It should be polished. When you turn the flywheel, you can see that the piston can reach to the top of the sleeve with a little bit of resistance. If it's still stuck half way and you cannot turn the flywheel to crank it when the heatsink is off, the engine is still not fully broken in yet.
Its a RR12L5 I have put another 4 tanks through so I am at the 10 tank with the WOT method, I still have a hard time turning the flywheel, in fact I may need another one, but I do feel that it becoming easier to turn . I am having temps of about 90 f ,and set the HSN very rich just before the engine dies, I have a lot of fuel coming out of the exhaust.
Usually how many tanks do you do on your engines?
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Old 04-07-2004, 08:34 PM   #7926
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Originally posted by InitialD
True and I agree with you but wouldn't running till the servos cannot turn anymore be dangerous?
hehe. Of course!

What I mean is, run the car until the battery runs out (the car stops, from failsafe or PCM mode). Then, take the car in, shut the engine off, and just play around with the controller. The servos will move, then die out quickly, hence draining the battery.
I know that this doesnt completely discharge the receiver battery, I think it is better than nothing. I have been doing this for quite a while already and my rx batteries have not had noticable problems.

Plus, i rather buy a new rx battery when the battery dies (havent had one die on me yet!). I have to buy quite a few batteries to make up the price of a discharger... unless u make your own.
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Old 04-07-2004, 08:36 PM   #7927
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Originally posted by Manticore
oh, that is one awesome battery checker !! i like it very much !

Good job manti, I just saw you have 9992 posts!
almost 10k
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Old 04-07-2004, 08:37 PM   #7928
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Originally posted by B

Good job manti, I just saw you have 9992 posts!
almost 10k
It doesnt matter to me !! i didnt notice that too !
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Old 04-07-2004, 08:39 PM   #7929
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Originally posted by Manticore
It doesnt matter to me !! i didnt notice that too !
9993!
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Old 04-07-2004, 09:13 PM   #7930
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Hi I would want your opinion on this post at rcu

"Idling an engine, letting it run slow, 1/4, 1/2 throttle is all incorrect. You want WOT after it warms up. YES WOT, even when it is brand new. This is in order to bring it up to the temp and fit the sleeve was designed to run at. Anything less and you are just leading your engine to an early death.

Yes, running at WOT slightly rich, but not 4 stroking rich is the proper way to do it. This explains the proper way and WHY it is the proper way. Here is some further explanation I wrote a while ago for newbie nitro guys that were still doing that incorrect idling method:

As for break-in, there is a whole lot of misunderstanding about this and basic engine operation. I have read and studied a lot of information on this and also by Dave Gierke who writes in RCCA and Model Airplane News (also by AirAge) about RC airplane and buggy engines and he's an expert. As well as Paris Racing, Stephen Bess, Clarance Lee, etc, in the research I have done over the last few years. It will take some time to convince yourself to bring a new engine to WOT but when you start to understand it and why it is correct, you will realize just how many people are completely breaking the engine totally incorrectly.


It’s important to learn the theory about how these engines run (2 stroke ABC, ABN, AAC), and how to break-in, especially because I see WAY TOO MANY people using the wrong procedure of idling many tanks of fuel through the engine. That is unnecessary and damaging which I will explain. Although we use the term “break-in”, by its word alone it is misleading because people wrongly assume it means to slowly and gradually bring an engine to tune by idling tanks of fuel but you will see why this is incorrect and unnecessarily wastes fuel too! Please be patient and read further to understand.

These engines use a sleeve around the piston to make the seal (piston doesn't have a ring) and it operates properly only with sufficient heat so that the sleeve can expand to its designed operating size and fit. All engines will be tight, especially when new, so on the initial runs, you want to have it get up to temp, so it can run how it is was designed to. By idling tanks and tanks through, overly rich and cool, the sleeve just wears MORE against the piston because it is not hot enough to expand to its operating size. And by doing that you are prematurely wearing out and ruining your engine. The piston/sleeve is designed to operate at running temps. Not doing this by running cool and rich on the bench leads to premature wear. By idling away tanks of fuel I GUARANTEE you are doing more harm than good. As long as the engine is warmed up first, you don’t have to drag out bringing it up to temp when it is brand new. It wont hurt or damage the working parts. These engines are very simple 2 stroke machines. They do not have extensive moving parts such as valves, cams, lifters, springs, etc. (like 4 strokers) so all this extra gentle, rich, cool operation is completely unnecessary (and worse it’s harmful). HOWEVER, the sleeve around the piston can be a delicate thing to maintain and it is not forgiving of improper treatment. And improper treatment of a piston and sleeve is running it at a temp it is not designed for. (either too cold or too hot, both are just as detrimental) Most often this is done by running it too rich which makes it too cold because the rich mixture doesn't generate enough combustion heat for proper sleeve expansion. Just as damaging can be an excessively lean run. If it is run overly lean for any length of time it will destroy the sleeve. (that is why fuels with castor oil as part of the lube mix are very good because they tolerate the too high heat of a very lean run and will help to save the sleeve if it is not run too lean for too long. but avoiding a lean run is essential when you know enough enough about engine tuning to avoid it)

Running a 2 stroke engine slow and rich makes it '4 stroke' which means it fires every other revolution, and that generates even less heat. It causes damage and wastes fuel as well! Using a fan is absolutely not necessary on it. Most important is to 'heat cycle' the engine at least 10 times to relieve the parts of manufacturing stresses. HEAT CYCLING REALLY IS WHAT BREAK IN IS ALL ABOUT. (I even think break-in should be called “Initial Heat Cycling” instead so that people understand what and why they are doing it.)

You run the engine in the car for 2 - 3 minutes at full throttle (yes, WOT, don’t baby it), ideally on a smooth paved level surface, after briefly warming up of course, and then shut down and repeat after the engine has fully cooled. Let it cool down completely. Heat cycling is the name of the game. You want it to come up to temp for a brief time, and cool down and repeat. After shutting down, adjust the flywheel so that the piston is at BDC (bottom dead center) so that it does not get stuck in the contracting/cooling sleeve, as can often happen. (If the piston should accidentally get stuck in the sleeve, preheat the cylinder to free the piston from the sleeve.)

During these initial runs YOU WANT the temps to be at least 200 F but not above 230-250 F. After break-in, running temps above 230F is fine. (in fact nitro engines perform best when run 250-300. below those temps they are less efficient and less powerful. However, going by the mixture is more important than trying to measure temp with heat guns, etc. which you may wind up doing inconsistently. The mixture setting on the High Speed Needle is critical in the first runs. It should be a rich and not lean setting. However it should not be so rich that it 4 strokes.

Also, to start a brand new engine it is very worthwhile to preheat the engine with a heat gun or hair dryer if it has a very tight piston/sleeve fit and you are having trouble turning it over to start it up. This will expand the sleeve some, and when you turn it over the piston will not excessively rub, or even get stuck in the sleeve (as sometimes can happen). Preheating really works well. You do want to run it on the rich side, but you want it to come up to temp also, just not more than 2-3 minutes in beginning runs, in order to keeps temps around 230F. Listen carefully to the exhaust noise or ‘note’, as you do not want it to be ‘4 stroking’. If it is, it needs to be leaned slowly until it runs 2 stroke. You can tell it is 4 stroking if it is very “boggy” and “hesitant” in acceleration and running. If it is making that “burbling” sound then it is 4 stroking which means it is running too rich and therefore too cold.

Everyone thinks they have to run it super cool and check to be sure temps are low. That's not what it is about. The reverse is true! Cool operation is damaging operation. Little, if any, break-in will occur unless it is heat cycled properly.

The manufactures can’t make a piston/sleeve turn over smoothly at room temp, because when the engine runs the sleeve will expand and there will be no seal at operating temp. See how that makes sense?!

So preheat it if necessary and don't run it cool, and heat cycle it, and you'll be good to go! After you have done this several times then you can gradually lean out the HSN to get best performance, but it should then be richened up just rich of peak to ensure it lasts long too. Running it at max peak rpm will lead to the shortest useful life of the piston and sleeve. If racing that is fine but if you are just playing you may want to run just a little richer than that peak setting. After the HSN is set then it is time to set the low and/or mid range needles and idling setting.

I see a lot of people idle the engine for a tank and then they let it cool off thinking that they are "heat cycling" it. However, because they are not running it up to WOT it is not generating enough heat to be of any use to a breakin/heat cycle. So, inadvertently by idling they are just letting the engine sleeve and piston wear away from the cold tight fit that they are allowing to happen when idling away on the bench. Research has shown that basically no breakin effect takes place AT ALL unless the engine is allowed to come up to operating temp for 2 minutes. So if you are idling away and then let it cool there is zero breakin/heat cycle benefit. But if you want to wear away the sleeve and piston fit then idling will definitely do it for you.

I hope this is helpful!!

P.S. If you want to hear it from him, read Dave Gierke’s article in the January 2002 issue of “RC Nitro” magazine! "
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Old 04-07-2004, 09:48 PM   #7931
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what does WOT stand for??
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Old 04-07-2004, 09:50 PM   #7932
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Originally posted by B
I have been doing this for quite a while already and my rx batteries have not had noticable problems.
Yup, that is if you have a failsafe... I sometimes inadvertantly do it myself without realising but with PCM failsafe, it can be dangerous too when the car stops dead in the middle or at the end of a straight.
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Old 04-07-2004, 09:53 PM   #7933
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Originally posted by Johnnytc3
what does WOT stand for??
Wide open tooshie
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Old 04-07-2004, 09:58 PM   #7934
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Originally posted by rodrigo1508
I still have a hard time turning the flywheel, in fact I may need another one, but I do feel that it becoming easier to turn .
I run about 15 to 20 tanks this way. You need to TAKE OFF the heatsink and turn the flywheel to check if the piston sleeve is broken in and not still get stuck.

As you go along, you need to lean the HSN little by little.
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Old 04-07-2004, 10:00 PM   #7935
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Originally posted by rodrigo1508
Hi I would want your opinion on this post at rcu
There are too many break in methods to follow. So they are neither wrong nor right. That is why break in methods are a little sensitive subject.
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