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Old 07-17-2008, 06:37 AM   #16
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hmm....some guys say that applying friction to the flywheel in order to stop it will cause harm to the conrod.

Burning the leftover fuel in the engine (before putting it away for some time) has the same effect as running lean. This is basically the same as the my methods above.

I'm so confused now
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Old 07-17-2008, 06:48 AM   #17
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Originally Posted by razor_clawzz View Post
hmm....some guys say that applying friction to the flywheel in order to stop it will cause harm to the conrod.
If you do something like jamming a screwdriver between the chassis and flywheel as a means to stop it abruptly ~ then yes, if could damage something.
But putting the toe of your shoe, or some tough guys even use their thumb, against the flywheel and thereby slowing it gently can do little or no damage to anything.

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Burning the leftover fuel in the engine (before putting it away for some time) has the same effect as running lean. This is basically the same as the my methods above.
Putting a motor away for "some time," which also would include the application of after-run oil, and stopping during a normal day of continuous running are two entirely different things. Putting a car/truck away and running it dry beforehand is done because it's a way to run all the fuel out of the enitre fuel system, fuel lines, carb, etc., because it's not recommended to store a nitro car with fuel still in it as nitro fuel is very moisture (as in water) sensitive and moisture absorbing.

But simply put, I have never heard of any internal combustion engine in which "running it lean to kill it" led to anything but shorter engine life and/or just plain killing it.
Especially with a 2-stroke, in which the engine lube (oil) is contained in the fuel, running lean robs the motor of its ever-important lubrication ~ not a good thing.
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Old 07-17-2008, 06:55 AM   #18
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I was told a perfect tuned motor will idle for 30 seconds then die. This will prevent all of the above worst case scenarios.. Of coarse I still just touch the flywheel at idle speed with my finger and its never broke any thing. We can get a bit to technical at times.

My son floods the pipe with the rubber tip on our Losi screwdriver or uses his shoe on the flywheel.

Sounds like your running to fat or to lean, you will have to temp it to see which way to turn the needle. Most likely to fat. Good luck.

The puzzling thing is that to burn up a plug like that seems you would not have any smoke so I'm going to say to fat.
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Old 07-17-2008, 06:59 AM   #19
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when i spoke to rody (the rb owner/designer) at the nats he told me to pinch the fuel line while killing the motor for the last time each day.. what he said was to empty the fuel tank as soon as your last race was over then fire up the engine and let it burn the remaining fuel out of the line and crankcase. that will get the excess fuel out of the motor that will cause bearing failure. he showed us bearings that have been taken care of in this manner compared to once that havent and the difference was amazing.
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Old 07-17-2008, 07:02 AM   #20
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when i spoke to rody (the rb owner/designer) at the nats he told me to pinch the fuel line while killing the motor for the last time each day...
Notice the use of the words, "for the last time each day."
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Old 07-17-2008, 08:34 AM   #21
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What difference does it make if it's after the last run for the day not?

I've always run my engines out of fuel and never had an issue with plug life. To stop the engine after a race, i normally plug the stinger with a screwdriver handle. And again, i've never had an issue. Personally, i believe pinching the fuel line is also an acceptable method of stopping an engine.... After all, it's generally at idle when you do it and if tuned correctly, should cut out quite quickly!

If you're having problems with burning out plugs, it will probably be poor tune, an air leak, or a shimming issue...
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Old 07-17-2008, 08:41 AM   #22
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Old 07-17-2008, 08:53 AM   #23
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Originally Posted by blktransam View Post
... but for some reason I keep killing the last coil in my v-spec with a p3 plug one head shim and byrons 20% engine temps are 250-260 with out side temps being in the 90's and a good smoke trail around the whole track....
250-260? Sounds lean. I run my Vspec with a P3 plug at 220-230. The P3's plugs last plenty long. Change the plugs every gallon just cause I don't want a failed plug when racing, but they are still good. I use 30% sidewinder.

Perhaps too lean? just a thought.
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Old 07-17-2008, 09:48 AM   #24
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I use temp only as a refrence. the engine has a very good smoke stream-lif I et it idle for 10 secs then hit the throttle it is snappy-no 4 stroking or lean idle. I think I need to just add a head shim and my plugs will be fine. trial and error. I did not start this thread for flame wars just some opinions.

Thanks,
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Old 07-17-2008, 09:58 AM   #25
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i only pinch the fuel line on te last run of the day.. intentionally leaning the motor by starving it of fuel causes premature plug wear
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Old 07-17-2008, 10:01 AM   #26
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I plug the carb. How good/bad is that?
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Old 07-17-2008, 02:34 PM   #27
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Quote:
Originally Posted by rocket-mtrsprts View Post
Both of your methods, pinching a fuel line and running a tank dry, lean out a motor and potentially causes damage.
If you pick up the car/truck while it's still running, turn it over exposing the bottom side, and put the toe of your shoe to the flywheel IT WILL stop it doing no harm to the motor.

Running the fuel out of the engine does absolutely no damage (it's probably not great if it runs out at full throttle). There is plenty of oil still in the crank case after it stops. It is important to run all of the burnable fuel out of the engine at the end of the day. The Alchohol causes condensation inside the engine which causes rust. Stopping the engine with some light pressure on the flywheel is the way to go though.

The plug issue could also be caused by slop developing in the con-rod bushing.
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Old 07-17-2008, 02:47 PM   #28
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Originally Posted by Davidka View Post
Running the fuel out of the engine does absolutely no damage (it's probably not great if it runs out at full throttle). There is plenty of oil still in the crank case after it stops. It is important to run all of the burnable fuel out of the engine at the end of the day. The Alchohol causes condensation inside the engine which causes rust. Stopping the engine with some light pressure on the flywheel is the way to go though.

The plug issue could also be caused by slop developing in the con-rod bushing.
WE'RE NOT TALKING ABOUT "the end of the day"

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.............................,-~*`¯lllllll`*~,................................... .......
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..................,-~*llllllllllllllllllllllllllllllllllllllllllll*-,..................................
...............,-*lllllllllllllllllllllllllllllllllllllllllllllllll lllll..................................
.............;*`lllllllllllllllllllllllllll,-~*~-,llllllllllllllllllll............................. ...
..............lllllllllllllllllllllllllll/.........;;;;llllllllllll,-`~-,...........................
...............lllllllllllllllllllll,-*...........`~-~-,...(.(¯`*,`,..........................
................llllllllllll,-~*.....................)_-..*`*;..)..........................
.................,-*`¯,*`)............,-~*`~................/.....................
..................|/.../.../~,......-~*,-~*`;................/...................
................./.../.../.../..,-,..*~,.`*~*................*....................
................|.../.../.../.*`..............................)....)¯`~,....... ...........
................|./.../..../.......)......,.)`*~-,............/....|..)...`~-,.............
..............././.../...,*`-,.....`-,...*`....,---........../...../..|.........¯```*~-,,,,
...............(..........)`*~-,....`*`.,-~*.,-*......|.../..../.../....................
................*-,.......`*-,...`~,..``.,,,-*..........|.,*...,*...|......................
...................*,.........`-,...)-,..............,-*`...,-*....(`-,...................
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Old 07-17-2008, 03:59 PM   #29
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the con-rod feels great...compared to some of my other v-specs in the past that never caused any plug issues I am just going to add a shim and run the odon plug
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Old 07-17-2008, 04:33 PM   #30
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Quote:
Originally Posted by rocket-mtrsprts View Post
or some tough guys even use their thumb,

I'm no tough guy, thumb firmly on the flywheel doesn't hurt.

Great way to learn where your idle should be...
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