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Old 06-24-2010, 05:11 PM   #1
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Default not much hair left on my head. Just about pulled it all out.

I cannot figure out why my ninja and vspec are idling so low. I have 2 fuel tanks and neither has a leak. New front bearings. New sleeve on ninja and a really good one on my vspec. New fuel lines with no bubbles. Have tried 3 different pipes and it does not matter. Pinch bolts are tight and properly installed on both engines. Needle housing is tight on both so is back plate. Glo plugs are new, and cooling heads are properly installed. I had my ninja sealed with lucky seven before i broke it down because it was doing the same thing.

New jug of fuel

new clutch

Carb boot maybe? don't know how to check that.

New batteries in my glo ignitor and so on and so on.

Once i am running it, it is ok for the most part. If i let it idle longer then a couple seconds it drops to a very low blubbery idle, as if it were very rich, and dies a few seconds after. doesn't matter how i tune it. I have my idle open almost 2mm and it still does it. When i start it up, i have to pull the trigger over and over so it won't die. So usually i just throw it on the ground and start running it. When it gets up to temp it still does it.

It has to be an airleak. But on both engines, tanks, lines and pipes? I am not the best tunner, but i can tune pretty well. Getting the darn thing to idle has never been a problem. No flame outs yet. Just very crappy idle.

ideas?
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Old 06-24-2010, 05:17 PM   #2
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I'm not the best tuner either but it sounds fat on bottom. You try the pinch test? Airleaks usually cause it to run leaner and idle higher i thought.
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Old 06-24-2010, 05:19 PM   #3
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I'm not the best tuner either but it sounds fat on bottom. You try the pinch test? Airleaks usually cause it to run leaner and idle higher i thought.
you are correct. That is why i am stumped. I put in new bearings, rod and got my P/S done by rayaracing. The engine runs crazy good, just idles for crap. It's not that big a deal and i am not worried. Just trying to get 2 good motors for the classic

you going?
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Old 06-24-2010, 05:23 PM   #4
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I'll be there with my 1 motor lol. I slapped new bearings in it last week and idled a half tank. Seems ok. Gonna try and get out to the track tomorrow to put a race tune on it. Hopefully the old front bearing wasn't leaking too much air and the tune will be close. Classic gonna be fun!
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Old 06-24-2010, 05:24 PM   #5
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when the engine is warmed up how long does it take to drop down to idle?
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Old 06-24-2010, 05:29 PM   #6
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when the engine is warmed up how long does it take to drop down to idle?
it's a little better when it gets warm. i would say 5 seconds before it drops and bogs out.

Ninja just got rebuilt so my settings are just a hair richer then race tune after 5 or 6 tanks.

I have to take into account the more hummid/hotter days too. Those both make my engine run leaner. But after reading my plugs they are slightly wet. More like a residue. Rich side of 100%.

oh. It's not my linkage either.
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Old 06-24-2010, 05:30 PM   #7
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it's a little better when it gets warm. i would say 5 seconds before it drops and bogs out.

Ninja just got rebuilt so my settings are just a hair richer then race tune after 5 or 6 tanks.

I have to take into account the more hummid/hotter days too. Those both make my engine run leaner. But after reading my plugs they are slightly wet. More like a residue. Rich side of 100%.
you are rich. you do not need to run rich when you do a pinch, just idle a tank then race tune it. lean it out, youll be good to go.
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Old 06-24-2010, 05:34 PM   #8
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Isn't it the hotter and more humid it is out the more the engine will "think" its rich. So you have to lean it out more.
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Old 06-24-2010, 05:35 PM   #9
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you are rich. you do not need to run rich when you do a pinch, just idle a tank then race tune it. lean it out, youll be good to go.


That all depends on the amount of the pinch that was done . If it was just to freshen it up with a partial , yes . A full pinch requires another break-in .
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Old 06-24-2010, 05:39 PM   #10
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you are rich. you do not need to run rich when you do a pinch, just idle a tank then race tune it. lean it out, youll be good to go.
yeah ok. It was pretty tight. Ray does awsome work. Will race tune tomorrow. My vspec it doing it as well. And i have leaned that one out for sure. Maybe that one is low on compression, although it does not feel like it. Will switch it out with another sleeve i have and see. Either way i will be alright. makes me mad when i can't figure something out.
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Old 06-24-2010, 05:41 PM   #11
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That all depends on the amount of the pinch that was done . If it was just to freshen it up with a partial , yes . A full pinch requires another break-in .
ok, this is my opinion, a correct pinch is i guess was u call a partial. puttin a full pinch like its new is wrong to do imo, your putting to much stress on the rod and crank.
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Old 06-24-2010, 05:43 PM   #12
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Sounds like a tune issue to me. Lean the bottom out and put the idle gap back to 1mm where it should be. Don't touch the idle gap. Use the LSN to set your idle. And stop being so paranoid! Nothing is wrong with your gear. Your tuning, well that's another story. Just be patient and don't be afraid to lean it out. As long as it is running well with a good smoke trail, you're good. And get the # of turns out of your head. Don't be afraid to go past 3.5 turns out on the bottom. I'm at about 2.75 on my speed now and it is running a perfect race tune. I bet you're just over thinking it too much!
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Old 06-24-2010, 05:45 PM   #13
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Isn't it the hotter and more humid it is out the more the engine will "think" its rich. So you have to lean it out more.
Hot temp = leaner

more humid = leaner

lower nitro = leaner

less oil = leaner

I have all of these conditions right now. My engine probably is to rich after all.

It's about 95 degrees outside with high humidity and 20% oddonnel fuel. p3 plug at sea level.

Is it me, or do engines run better in cold weather?
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Old 06-24-2010, 05:46 PM   #14
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Dreaux you coming to the cajun classic this weekend get someone to look at it. They will be out theere all weekkend.
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Old 06-24-2010, 05:48 PM   #15
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Originally Posted by dreaux View Post
Hot temp = leaner

more humid = leaner

lower nitro = leaner

less oil = leaner

I have all of these conditions right now. My engine probably is to rich after all.

It's about 95 degrees outside with high humidity and 20% oddonnel fuel. p3 plug at sea level.

Is it me, or do engines run better in cold weather?
Now you're on the right track Dreaux. Remember 20% fuel does tune differently than 30% fuel. My engines are tuned much leaner to achieve a race tune than someone running 30% fuel. Lean it out!

And yes engines run much better in cooler temps! I ran in very similar conditions to what you described last weekend, and I had to lean my engines out quite a bit. Lean it out!
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