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Discussion Starter · #1 ·
ok guys i just got out to adjust my jetting and i'm running a 180 main,50 pilot, 2 turns, and a gyt-r 4th pos. well i took it out and it starts up great and idles awsome. but when i start moving and roll the throttle form 1/4 it boggs. can it be my needle clip. i tried 4th pos with a 170 main,175 main, all with a 45 pilot and a 48 pilot. with about 11/2 - 2 turns. i live in jersey sea level. i have a full hmf, cam mod, airfilter. i think i'm almost there with the jetting i just want it to be perfect. let me here what u guys think ??? thanks
 

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Discussion Starter · #3 ·
well i'm at 1/4 when i start to roll the throttle. then it bogs.
 

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It is only perfect when it runs the best.

We always put the airscrew at 1.5 to jet, then get the best jets possible, until it runs the best

then you will have equal distance for the needle to go up or down when at last you adjust the airscrew.

so first off, put that airscrew at 1.5


now it BOGS could be too lean or too rich.

SO how to decide?

ANSWER!

pull the choke out 1/2 click and try and run it.

if it runs WORSE NOW then you were too rich on the bogging!

so go down on the clip only on
and run it with and without choke


If it bogs on the TOP then go to a 175 main.






NEVER CHANGE TWO THINGS AT OPNCE or you will never learn



i think a pilot of 50 in this cold weather is great!

since it IDLES GREAT the pilot is right on.

play with the clip

those are the nesxt two moves I would try.




if the choke made it run WORSE then go down one needle

if the choke made it better, go to needle #6


you can also try the airbox lid, if you put the airbox lid on and it runs WORSE then you were TOO RICH and you have to go down one needle clips

if you put the airbox lid on and it runs BETTER then you were too lean and you have to up one needle clip

you can EVENTUALLY jet right by just trying every needle combination, but shoot that woould take a week.

so use the choke trick and airbox lid trick to speed things up

your idle is perfect
fiddle with the needle

then lastly adjust the airscrew one way then another.

GOOD JETTING!
 

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Originally posted by daddogrider@Feb 8 2004, 11:33 PM







NEVER CHANGE TWO THINGS AT OPNCE or you will never learn


GOOD JETTING!
I re-jetted my two YFZ's after reading the daddogs dogriders page.

I bookmarked (but lost when changed my old computer) a page where daddog mentioned simply getting the re jet kit from your Yamaha dealer, and daddog gave some adjusting tips. He may have changed the info on that page.

Several of my neighbors brought their YFZ's over and we had a dad dogs re jetting blockparty. No booze until we finished.

We all run fast, and easily beat the feared Predator quads at the dunes.

I think the confusion with re jetting suggestions (from different sources not just daddogs) is sometimes it isn't clear if the clip recomendation is for the stock or NCQV needle, often no mention with the boxtop on or off, and often airmix screw setting is omitted. Ya gotta dig around daddogs site for little nuggets of info to pull it all together.

Following daddogs basic guide from his dogriders page ( that I can no longer find):
165 main/45 pilot/ K&N/tuneable pipe/ncqv needle 3rd clip/2 turns airmix/ehs lid

No hesitation off idle, great performance low and top end, starts with no choke in 30 degree weather.

Absolutely, positively blows built predators off the dunes.

The cam mod/170 mainjet YFZ's are faster, no question.

Do and perfect 1 mod at a time, or you'll be chaseing your tail trying to tune, or find your mistakes.

Patience, time and a good shop light are the key.
And do it sober.
 

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Originally posted by yfz450 kid@Feb 10 2004, 04:20 AM

And do it sober.
I don't know about all that :D
 
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