ATV Florida Forum

ok   taking off   the air box  where would you start  with the mian  jets way up high or just a lil bit over stock? if anyone knows something its greatly   apricateed   will be staring  next week to mess with jetting 2005 kfx 400

ok here #1 read the damn manual that the jets come in  duh  lol
kfx 400  sucks;  get back to work on the eiger

no  4x4 suck lol    kfx much better and alot more fun to ride

Does it have an aftermarket pipe? Stock pipe? Baffle taken out? K&N or foam filter?

esr air box elimination         and got baffle taken out and power tip put on   for now

the k and n style filter  with the outa wears on it

Here are a couple of links that might help.

http://www.z400central.com/invision/index.php?showtopic=80881&hl=JETTING+NO+AIRBOX+STOCK+EXHAUST+BAFFLE

http://www.z400central.com/invision/index.php?showtopic=39000&hl=JETTING+NO+AIRBOX+STOCK+EXHAUST+BAFFLE

id go up 10 on the main jet and call it good. all you need to do is run the thing wot, if it pops, its lean, if it winds out fine, your ok. i doubt you changed anything enough to need to play with the needle, but if so, thats something you will have to get a feel for.

i got the dyno jet  jet kit   so i can put the new needle  ad stuff  out of it  adjustable fuel screw  you all think hats good idea?   and thank you all for the help looks like i would be around   150 or up main jet and 3 or 4 on needle  it should be good    ill keep u all posted   on the prog

I have a friend with 2 Z400. They both have a closed airbox with just the snorkle removed. They both have a Yoshimura slip on. He is running a 150 in one and a 152 in the other. I think you would be closer to 160.

Remember dyno jets are different than stock ones.

Width------Keihin # -- DynoJets # -- Mikuni #
0.0350---- 92.5--------- 92----------- 86.3
0.0360---- 95----------- 94----------- 88.1
0.0370---- 97.5--------- 96----------- 90.0
0.0380---- 100---------- 98----------- 91.9
0.0390---- 102.5------- 100---------- 93.8
0.0400---- 105--------- 102---------- 95.6
0.0410---- 107.5------- 104---------- 97.5
0.0420---- 110--------- 106---------- 99.4
0.0430---- 112.5------- 108--------- 101.3
0.0440---- 115--------- 110--------- 103.1
0.0450---- 117.5------- 112--------- 105.0
0.0460---- 120--------- 114--------- 106.9
0.0470---- 122.5------- 116--------- 108.8
0.0480---- 125--------- 118--------- 110.6
0.0490---- 127.5------- 120--------- 112.5
0.0500---- 130--------- 122--------- 114.4
0.0510---- 132.5------- 124--------- 116.3
0.0520---- 135--------- 126--------- 118.1
0.0530---- 137.5------- 128--------- 120.0
0.0540---- 140--------- 130--------- 121.9
0.0550---- 142.5------- 132--------- 123.8
0.0560---- 145--------- 134--------- 125.6
0.0570---- 147.5------- 136--------- 127.5
0.0580---- 150--------- 138--------- 129.4
0.0590---- 152.5------- 140--------- 131.3
0.0600---- 155--------- 142--------- 133.1
0.0610---- 157.5------- 144--------- 135.0
0.0620---- 160--------- 146--------- 136.9
0.0630---- 162.5------- 148--------- 138.8
0.0640---- 165--------- 150--------- 140.6
0.0650---- 167.5------- 152--------- 142.5
0.0660---- 170--------- 154--------- 144.4
0.0670---- 172.5------- 156--------- 146.3
0.0680---- 175--------- 158--------- 148.1
0.0690---- 177.5------- 160--------- 150.0
0.0700---- 180--------- 162--------- 151.9
0.0710---- 182.5------- 164--------- 153.8
0.0720---- 185--------- 166--------- 155.6
0.0730---- 187.5------- 168--------- 157.5
0.0740---- 190--------- 170--------- 159.4
0.0750---- 192.5------- 172--------- 161.3
0.0760---- 195--------- 174--------- 163.1
0.0770---- 197.5------- 176--------- 165.0
0.0780---- 200--------- 178--------- 166.9
0.0790---- 202.5------- 180--------- 168.8
0.0800---- 205--------- 182--------- 170.6
0.0810---- 207.5------- 184--------- 172.5
0.0820---- 210--------- 186--------- 174.4
0.0830---- 212.5------- 188--------- 176.3
0.0840---- 215--------- 190--------- 178.1
0.0850---- 217.5------- 192--------- 180.0
0.0860---- 220--------- 194--------- 181.9
0.0870---- 222.5------- 196--------- 183.7
0.0880---- 225--------- 198--------- 185.6
0.0890---- 227.5------- 200--------- 187.5

basically follow dynojets instructions for stage 1 accept for their main jet recommendation becasue it is for the lid being on. put the dynojet clip in on the 3rd clip, turn the air/fuel screw 3.5 turns out from all the way down. and id probably go with something in the 135-140 range for the main jet. and then go from their. if you put a 140 in and it feels to be a bit rich, you could always take the end cap off your exhaust and it may be enough to get it right on the money.

my end cap is hollowed  out its just a crome tip  with like 3 inch outlet   no screen or nothing   lol  shots a flame out it now if i am on gas real hardthen  get off it   just cut fenders  today my parts shoul d be  in soon ill be messing with it this weekend

with no endcap, and no airlid, id say a 140 main jet should be about right. when you get your jet kit, you could probably just folow the stage 2 instruction which are for a pipe and intake and then instead of using the 150 main jet that they recommend, go with a 140.

i got no box   not just no lid

same thing as far as jetting, only difference is you have to clean your filter every ride lol. i never really understood having no airbox. i built my uncle a blaster with a biger carb and ran it with no box, becasue i couldn't with the 34mm carb, and it was just kind of impractical.

its all about looks  my freind    lol ;)   no  just kiddin look at race cars   they run  filter right on top  of carb  why not  have  a restricted box  or snorkle around it   more  air plus more  fuel  equel more power   ;D   plus it makes me keep  the bike out of mud and water   i always get looked at funny when its covered  in mud  lol

lol, race cars have a hood and fender wells. the air is there either way, its just a mater of if you want aitr out of a shielded box, or dirt mixed with air flinging off of your tires lol. im just kiding with you tho, open filters are fine. id just rather a box for when its wet out.

yea its all good

ok   i got the lrd complete   system   to add to my bike now.   



my jetting is already   3rd clip on needle
160 main jet
and fuel screw is out  3.5 turns


i have dyno jet jet kit   how much more will i have to go up on the main you think 165 or 170?

i got header and new pipe to be put on   thanx agian or the help