2007 YFZ-450 Jetting?

[smaho007]

Hello everyone I am new to posting and am not quite sure if I am doin everything right but anyways I have a 2007 YFZ-450 with a Toomey racing pipe,K&N extream power lid, K&N replacement filter, and the GYT-R Jet kit. My jetting is at 170 main, 45 pilot, 4th clip on the NCVQ needle and 2.5 turns on the air screw. I also put the o ring mod on the AP. It runs really good and the plug is burning nice. I am wondering if it sounds like I am on the right track or what ya know. I am in NY at about 600 ft in elevation I think.Any info would be Great. Thanks Steve

[YFZKID]

dude i got the same set up! 07 yfz, mod squad filter kit,but a dial a jet,ket kit and a toomey pipe! i had many issues with jetting mine also,i would suggest 2 other things that help the yfz out,a boysean quick shot 2 and a aftermarket fuel air mixture screw,so you can adjust as the weather changes....but other than that i think you are on the right track
jus send me any messages if you have any issues with you yfz!

[P1M]

I also think you should be pretty close. The NCQV needle is great.... Also works good on WR450's. Cleans them up nice.

[smaho007]

YFZKID thanks for the info man.. I def. want the boysen QS2 and the whole airscrew thing sounds alot easier than twistin the carb everytime ya know.. But another question will the AP mod affect the Quickshot? well either way if it does I can just take the o ring off right.. I have been doin a ton of research on this YFZ man and it is one mean monster when its jetted and runnin right..What about the cam mod you have any info on that..or is that just a bad idea in my situation...anyways thankz for all the help and stuff its def. good to hear from others and figure what they did in there situations. Oh yeah YFZKID you gotta nice quad man.. Do you like the toomey? Is your quiet core and spark arrestor in it or not. Mine is. Does it really make a difference or what. Hit me back man, tell me what you think...Thankz Again...Later

[Dirtbikindad393]

smaho007,

Do you get any popping on decel with that set up?

I would try bumping the pilot up to a 48. The 170 is pretty fat for a 45 pilot and 2.5 is about the max on the fuel screw. To give yourself more fuel screw adjustment if you go to the 48 you would want to run about 1.5 on the fuel screw. Of course you would have to try it and dial it in to your bike but I think a 48 would bring the bottom end alive a little more. I had the 170/48 set up in my '06 YZ450F and it was a little rich. I ended up backing down to the 168/45 and that runs cleaner and still has a lot of snap but 2 wheels is a little different than 4 also. Let us know if you try it.

[YFZKID]

honestly i am not too familiar with the ap mod! but if you were to install the quick shot just removed the oring you installed for the ap mod and use the factory orings.with the quick shot you must use the factory orings or even just go buy new ones they are only bout 3 bucks for both of them! here is a link to the cam mod http://www.allthingsmoto.com/forums/...video-s-12298/ with a little work the yfz will outright fly! i do like the toomey,i ran it for a while without the quiet core installed and it was a little too loud! my friends would get mad when they were riding behind me! so i installed the quiet core..but other than that i am really pleased with the quality of the toomey.i think with it out you have to constantly tweak the fuel air mixture screw,and with it in you can basically set it once and go ride!

[smaho007]

alright so if I go with the 168/45 what should the fuel/air screw be at.. Does the screw control fuel or air? I am not really sure what it does exactly but I do know I had it at 2 turns out then I installed the k&n lid and filter and it seemed to have a little less low and a little more top so I gave it another 1/2 a turn and it seemed to fix the low a little but I think it could be a little crisper so thats why I might go with the 168/45. It doesn't really pop or backfire but occationaly it will like....burp almost. so I don't know what would cause that..or how to crispen it up but let me know..Also do think the cam mod really gives it a whole lot more or not I don't really know if I want to do the cam mod but if it does do alot for it I will. but I also don't wanna meltdown. so I don't really know what to do so...let me know what you think ..thankz again the info is great.

[YFZKID]

i am not too sure what the gytr jet kit numbers are! i used the dial a jet kit and the numbers are diffrent! i am thinking main jet like 185 pilot jet 45 and the 3rd clip on the needle..i think!! i cannot remember exactly!! the fuel air mixture basically explains it self the more turns one way the more air,turn the other more fuel! i think mine is like 2 1/2 out but the quick shot 2 will crispen up the bottom and top end..i am not sure about the cam mod,i figure if it aint broke dont fix it! and if it dont need it dont do it!! but if i had to replace the cams i would do the cam mod then,but until something happens with them or you need to replace them,then i would not do a cam mod

[smaho007]

Ok so I changed the jetting a little I tried the 168/45 but it toped out really quick and didn't have as much top end. So I went back to a 170/45 and changed the needle clip to #3 and I also turned the air/fuel screw to 1 3/4 open and it seems to run awesome. It has a lot of pull throughout the whole entire powerband. There is still a slight pop on deceleration way down low, I don't think its anything to worry about but I would really like to get it dialed right in ya know. I raced my uncle's 03 banshee at a rolling start and I pulled on him the whole time but we seem to be pretty even on the top. I bet from a dead stop for like a while I would have him but I am not really to worried about that either. But my jetting now is 170/main, 45/pilot, 3rd clip on the needle, and 1 3/4 turns on the mixture any info would be great. I don't really wanna change the jetting to much it seems really close but any tips on really dialing them in would be great. The plug is a pretty nice chocolate so I am very close and I don't really wanna richen it but maybe another 1/4 turn in on the screw to make it 1 1/2 turns. Maybe that will get rid of that exess fuel causing the pop down low. Anyways let me know what you think..Thanx.

[smaho007]

Ok so its been a while and I have a couple of Questions. I recently bought a wirtz racing A/P cover and installed it and it told me to adjust the a/p timing to 2.5 mm. So I did everything it told me to do and it seemed to have a really bad bog on the idle curcuit with the sparky in the toomey. I pulled the sparky out and it runs better no bog or anything, but I also don't know if my fuel screw it set right or not. The plug actually looks pretty good so I am a little confused. It does backfire on the deceleration but I have read a couple of forums that say it could be normal. I am still running the 170/m 45/p ncvq needle on clip#3 and 1 3/4 turns on the fuel screw. Any info will be great thanx. Oh and also I just got an HMF sport series slip on for my girlfriends 07 raptor 350 and have no idea where to start the jetting on that. I've read a little about it but not enough so any info on that...,would also be great.

[giesdog]

i don't know much about the ap cover, your jetting sounds pretty good except the #3 clip on needle. I would at least try 4 clip. stock is 3, I have 172 main 45 pilot 5th clip, just set it up like that and it runs well, may still be a little too rich. I started with 175 main 6th clip and 48 pilot. did this so I could work my way down once I installed my new pipe filter and powerbowl with accelerator pump to get it jetted right on. I knew it would be rich and it was. I couldn't hit rev limiter with throttle all the way it would pop too much. of course that was when it was 40 degrees outside, now it is 90. I will probably try 170 4th clip but stay with 45 pilot. 45 pilot is probably best bet for 80% of quads. unless you have really built motor it should be fine. I try to leave my mixture screw at 2, I haven't been able to tell much by adjusting it. thougn at 1.5 it tends to pop more than at 2. My guess is you popping on decel is due to a lean clip setting which controls fuel from 1/4 to 3/4 throttle. let me know what you think, I may be way off.