I finally made it to the shop to get a couple of jets, and got the baffle out, lid off, and cam mod,put the 168 main in, 45 pilot, moved the clip on the stock needle down to the 5th position. And all I can say is WOW :O its almost like I bought a whole new bike for the $8 bucks the jets cost me. :lol
OK fellas I will send you the JD instructions but to everyone else let me make this clear these just tell you mechanically how to jet, not how to dial your bike in. OK
Moving the needle down to the 6th clip will help a little but you are still gonna be lean at 3/4-WOT cause the fuel cant flow past the small stock main jet.
Originally posted by McDowell@Mar 1 2004, 07:19 AM ok, here it goes:
with an HMF slip-on and air box lid on, i'm now at a 170 main, YZ NCVQ needle 3rd clip, 48 pilot, Zip-Ty screw at 2.5 out. seems ok except if i crack the throttle open hard from idle it dies at about 1/4 throttle. does fine if i open it slower but just quits if i open it quick. i tried the needle at 4 w/ same result. i also adjusted the screw everywhere from 1 to 3 turns w/ same basic result. my brother's YFZ is identical except 175 main and stock needle stock clip and dies at the same point.
my thought is that the pilot is a tad too big and i should try a 45.
ANY helpful suggestion would be appreciated. thanks.
Originally posted by superdave@Mar 10 2004, 06:16 AM Yeh, I work part time at a Yamaha shop so I I bought the jet kit form the shop. My understanding is that the YZ450 needle is the same thing. SO all you need is a couple of main jets and one or two pilots. ...I started working at the shop after I bought the 450 so I did not get a great deal on it, but parts are cheaper......
Originally posted by FAST1@Mar 26 2004, 07:07 PM
Interestingly, when we discussed jetting specs last summer (mid- August), you suggested I run a 168 main, 3rd clip on NCVQ needle, 45 pilot and that was with a full GYT-R exhaust and a FOAM GYT-R filter with lid off. Now you suggest the same jetting for a K&N which obviously flows more air than the foam filter.
I would allways start rich and know your rich, then lean down the main and needle clip. Your even running a 172 main, correct?
I did and I realized that I and alot of other folks were actually jetted richer than need be.
And yes I do run a 172 48 pilot, 5th clip on NCVQ needle and 1.5 turns out on the mixture screw.
With
ESR pipe
ESR intake (no airbox, more air than just a K&N in the box)
YZ EX cam
and head cleaned up (reason for bigger main, was 170 and 4th clip before)
Yup your jetting specs sound right on to me, I told you to go down in main size a while back.
You are jetted close to me, I am at $2200ft and have the head ported so I am just alittle bit richer.
As for Glamis its at sea level so yes you will have to jet alittle richer than you are now.
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