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Here at sea level (Long Island NY), I have the HMF Comp-Series slip on, Lid off with K&N air filter/Modquad adapter. Jets that worked perfect for me are: 168 main jet, 45 pilot, NCVQ needle clip#2. No backfire or sputter on accel/decel and pulls hard through the gears (Thanks Terse! Man knows his ishhh!)
 

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Hey guys, I need to rejett my stock 06. Can I go and just buy a 168m kevin jet and a 45p kehin car and install it or do o need a aftermarket needle ?

Stratton ?
 

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Does,this sound like a jetting issue? (Video)

watch this clip n see what you guys think....runs PERFECT some days and horrible the next. At one point it ran fine for a couple months. Mods are in sig picture and jetting is now at 45 pilot-175 main NVCQ needle at 3rd clip..

2005 yfz ignition/fuel problem shot with a hero 2 - YouTube
 

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Mods: Cam mod, full curtis sparks, aftermarket intake with no lid

175 Main
42 Pilot
2.5 turns out on fuel
NCVQ on #2

Gonna pick up a 45 pilot instead and maybe a smaller jet, haven't gotten a chance to ride it yet still waiting on a starter but I should be close to right correct ?
 

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Mods: Cam mod, full curtis sparks, aftermarket intake with no lid

175 Main
42 Pilot
2.5 turns out on fuel
NCVQ on #2

Gonna pick up a 45 pilot instead and maybe a smaller jet, haven't gotten a chance to ride it yet still waiting on a starter but I should be close to right correct ?
Elevation?
 

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you might be fat on top but you leaned the 175 out by going to the 2nd clip.
 

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Sorry I've committed a cardinal sin, I didn't read all 53 pages of this thread. First five and last one I did. I've been trying to dial mine in and need some clarification on something.

When we refer to the mixture screw turns, is 1 turn 360 degrees? Or 90 degrees? On my screw it's labeled 1 2 3 4. And never seen this clarified. I can't get it to idle for the life of me.

Thanks.

05 yfz -
Pnp
Lrd exh.
Cam mod
Lid off
Modified intake tube
185 main, 45 pilot, 90 on the other one I can't remember name of right now
Boysen big shot w/50 leak jet.
 

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Sorry I've committed a cardinal sin, I didn't read all 53 pages of this thread. First five and last one I did. I've been trying to dial mine in and need some clarification on something.

When we refer to the mixture screw turns, is 1 turn 360 degrees? Or 90 degrees? On my screw it's labeled 1 2 3 4. And never seen this clarified. I can't get it to idle for the life of me.

Thanks.

05 yfz -
Pnp
Lrd exh.
Cam mod
Lid off
Modified intake tube
185 main, 45 pilot, 90 on the other one I can't remember name of right now
Boysen big shot w/50 leak jet.
Yes 1 turn equals 360 degrees, think you might wanna drop down a jet size if that's a yammie jet
 

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Need help with jetting. Currently at sea level with gytr slip on exhaust, FCI intake, no lid on airbox, and zip tie mod. I am currently running 175m, 48p, clip on fourth notch of gytr needle. I am getting a lot of popping when pushing the throttle and almost immediate bog/almost engine kill until higher rpms.
 

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Jetting looks rich all the way around to me. I would try a 45 pilot. Only change one thing at a time so you know what the change did. Whats your screw at?
 

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Jetting looks rich all the way around to me. I would try a 45 pilot. Only change one thing at a time so you know what the change did. Whats your screw at?
My screw is at 2 turns out. I will try going back to the 45p. I think I am getting my jetting screwed up because I was asking for help for when I ride at 3k-6k elevation. I believe everyone feed back now was for when I was at that elevation...
 

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I think I'm thinking about this arse backwards....when jetting for elevation does your jet size get smaller or larger?
 

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Jetting at higher altitudes will be leaner than jetting at sea level for any given machine. For jets, numerically, the number corresponds with the size of the hole. For example, a 160 has a smaller orifice than a 180. Your jetting does seem really fat, as dust n' u suggested, unless you have more internal work done. That almost seems like you have big-bore jetting... You should be closer to a 45 pilot, NCVQ needle on the third clip position, and a 168 main. That should get you in the ballpark, unless you have other internal mods that a previous owner installed or something... One quick trick that I like to use is to pull the choke in whatever area you're trying to diagnose. It's just a quick and dirty way to see if you're rich or lean. If it runs better when you pull the choke, you're lean. If it runs worse, you're already rich. Good luck.
 

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Jetting at higher altitudes will be leaner than jetting at sea level for any given machine. For jets, numerically, the number corresponds with the size of the hole. For example, a 160 has a smaller orifice than a 180. Your jetting does seem really fat, as dust n' u suggested, unless you have more internal work done. That almost seems like you have big-bore jetting... You should be closer to a 45 pilot, NCVQ needle on the third clip position, and a 168 main. That should get you in the ballpark, unless you have other internal mods that a previous owner installed or something... One quick trick that I like to use is to pull the choke in whatever area you're trying to diagnose. It's just a quick and dirty way to see if you're rich or lean. If it runs better when you pull the choke, you're lean. If it runs worse, you're already rich. Good luck.
"Really fat" meaning too much fuel not enough air?

"Should be closer" to a 168 meaning for sea level or higher elevation?

I live about sea level but I don't get to ride until I am at about 3k-6k. So if I find where I am good at sea level should my jetting go up in size or down in size?
 

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If you're jetting for sea level, but riding at 3k-6k feet, you're going to have problems. If you jet it properly for sea level, the appropriate jetting will be leaner for the higher altitude-- meaning that the jets required for the higher altitude will be smaller. You should just try and get in touch with a shop who does frequent jetting or try and find a jetting chart to see what you should be at whenever you change from sea level to your riding altitude because it's ridiculous to sit here and troubleshoot this if the jetting you're shooting for isn't even the jetting that's required for wherever you're going to ride.
 

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I don't think it's ridiculous to sit here and try to figure out what I am doing wrong. I am just trying to figure out which direction I am suppose to adjust jetting wise once I get my jetting dialed in around sea level. Thanks for the great input and I now have a better understanding as to what I need to do.
 

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I ended going down to a 168m, 45p, two turns out on the fuel screw. My bike is running good now with no hesitation. My only question now is; what does it mean if in neutral I blip the throttle and the rpms stay high and eventually come back down to idle?
 
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