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yfz450 revs way to high, no it's not my idle

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Old Aug 28, 2007 | 11:21 PM
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Default yfz450 revs way to high, no it's not my idle

The bike starts fine and idles fine. Once I touch the throttle she stays at a high rev. When I put the bike in gear and release the clucth she goes back down to a nice idle or if i'm riding and I come to a stop with the clutch in or out she idles high. What the hell is that...The stock settings did this and then I jetted her. 168m,45pj and 5th clip with 2 turns out. Still the high revs. Any help would be cool, i'll try anything at this point. Thanks...
 
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Old Aug 29, 2007 | 10:32 AM
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From: Chickasha, OK
Default yfz450 revs way to high, no it's not my idle

Sounds like may have vacuum leak somewhere. Have you messed with the carb lately? Check your boot, see if it's cracked and sucking air. You can get a can of carb cleaner and start the bike. Spray the cleaner lightly around the carb. If it revs higher there is a leak somewhere.
 
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Old Aug 29, 2007 | 01:59 PM
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Default yfz450 revs way to high, no it's not my idle

Thanks, I will try that with the carb cleaner. I just bought the bike and it had that problem. It was all stock so I jetted it and it still revs high. So hopefully there is a leak so I can pin point it and fix it. Thanks again.
 
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Old Sep 6, 2007 | 11:03 PM
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Default yfz450 revs way to high, no it's not my idle

I'm done, the quad is running perfect. I had the stock needle in the carb, NDSR, on the 5th clip and replaced it with the NFSR, aka NCVQ on earlier models, and put that on the 5th clip. So now I can run with the baffle out and it does not rev high. Yee Haa. The needles looked identical, but made the difference. I also did the oil upgrade, pump and squirter, myself if anyone is interested along with many other mods.
 
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Old Sep 7, 2007 | 10:35 AM
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Default yfz450 revs way to high, no it's not my idle

Good deal. Let me ask you a couple questions here.

On the needle. I take off the top of the carb. Use a allan to get the top off and expose the needle. But how does it come out? I can't get the carriage out because I've almost rounded off the head on it. Tips???

On the oil mod, what does that take? I'm confident I can handle anything but, I don't want to tear it down too far until winter.

Thanks.
 
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Old Sep 7, 2007 | 12:33 PM
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Default yfz450 revs way to high, no it's not my idle

I'm not sure what you mean by "I can't get the carriage out because I've almost rounded off the head on it". The simple way I get the needle out is to rotate the throttle carrirge, the round thing that holds the throttle cable, to expose the needle inside the throttle body and lift it out from the inside. Hope that helps.

As far as the oil mod goes I did alot of research on the other forums and copied all the pics I could that others have posted and just winged it. By winging it you pretty much figure it out as you go. It became very simple after that. When winter comes and you have a couple of questions you can write back then. Until then, enjoy the rest of summer/fall.
 
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Old Sep 7, 2007 | 01:28 PM
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From: Chickasha, OK
Default yfz450 revs way to high, no it's not my idle

Ahh, I see. Sorry if not clear but, either way you covered what I was looking for. Thx.
 
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