Jet needle

[Jimsyfz]

Hey guys, looking at changing my needle out on the yfz. Any good suggestions? Mine pops a little on deceleration.

Thanks,

[Jeremy]

A 'small' pop(s) on decel isn't always bad and certainly doesnt mean you need to adjust your needle. Have you adjusted the fuel screw?

[Jimsyfz]

Yes I have adjusted the fuel screw, but it still does it. Not so bad with the new pipe tho. Quad runs strong and all, just have carb off for some other work I'm doing to the frame, so figured I'd get some input on needles. I know they sell supposedly better ones. I just raised the stocker 1 groove and have been running it that way for a while now.

[Jeremy]

Maybe you just have an air leak somewhere. Is your headpipe tight?

[Jimsyfz]

Ya, I just put one of the new TDC pipes on the quad. I like it so far. Have been all over it carb and exhaust. Will try playing with the fuel screw some more.

Thanks

[easman31]

ofcourse this is with no airbox lid, and after market filter
Main Jet Needle Clip position Pilot Air/Fuel screw

175 NCVQ 4th from top 45 2.5 turns out from closed

[Bowtie]

Decel pop is usually associated with being lean on the bottom end of the carb. What happens is the slide slams shut, and there is no fuel. Bump the pilot jet up a size and then re-adjust the air/fuel mix to get a clean idle. The needle doesn't come into play until 1/4 to 3/4 throttle.

[Jimsyfz]

ofcourse this is with no airbox lid, and after market filter
Main Jet Needle Clip position Pilot Air/Fuel screw

175 NCVQ 4th from top 45 2.5 turns out from closed

That is like the exact set up I'm running. Except I have the stock needle. And fuel screw is around 3.5 turns. Think I'll try a 48 pilot and re- adjust.

Also, it doesn't like to return to idle right. kind a hangs up high and then settles down and wants to stall.??? But not all the time. Have checked for airleaks and all that.

[easman31]

the kind of needle makes a big difference..Also make sure the head pipe were it meets the head is snug..

[Bowtie]

Flush out the thumb throttle and cable and make sure they are free flowing. Double check the slide and make sure it's cleaned out. Pay attention to how the slide comes out, if you install the plate upside down, you will fight a lean condition.