jetting placement

[honda400ex2003]

Just for reference for me, i am making a thread with this info on it. It shows where each part of the carb is in effect. now i can just search for my name and find this lol. steve

My jetting suggestions:
http://img121.imageshack.us/img121/2353/newpicture1d.jpg (http://img121.imageshack.us/i/newpicture1d.jpg/)

Jetting placement chart:

[honda400ex2003]

I know this is on here already. lol now i know what to search easy when i want to find this stuff. steve

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

[honda400ex2003]

pilot adjustment procedure

http://s759.photobucket.com/albums/xx239/rocky_mtn_honda/TRX400EX%20Manual%20Pages/?action=view&current=carbadjustment.jpg

same with the picture.

http://s759.photobucket.com/albums/xx239/rocky_mtn_honda/TRX400EX%20Manual%20Pages/?action=view&current=carbadjustment.jpg

[ridein'red7]

mods put this in faq!!

[honda400ex2003]

most of it is hidden in there or other places. I just get tired of trying to search for it all the time. so i made my own so i know what to search for with my name to get the correct thread. steve

[honda400ex2003]

plug chopping
the plug chop is an essential step in setting up jetting. not only does it help you get good performance, but more importantly, it helps you make sure yr bike is not running so lean that it will blow up!

1. wind it out! . warm the bike up well (5-10 min) with a new or fairly clean plug, correctly gapped, then wind the bike out in a gear. generally, i like to do this in 3d, but it depends how fast your bike goes in each gear and where you're doing this test (trying to run a bike out in 4th is not advisable in, say, a school zone). at least get into 2d.

2. hold it there ... even though you will be nervous, hold it in gear at max rpm for a while... what you are trying to do here is simulate the hardest use the bike will ever conceivably see. if you jet for the most stressful conditions, then yr normal use will be well within safe margins. keep yr hand on the clutch, as you could (doubt it, though) seize if you are jetted too lean to begin with. as always, use yr own judgment!

3. kill it. simultaneously hit the kill switch and pull in the clutch. hitting the kill stops the plug sparking; pulling the clutch stops the clutch from turning the engine over (bringing in more unburnt fuel). thus, you get a perfect picture of what the sparkplug looks like at the moment you hit the kill switch.

4. pull over, pull the plug out you will want to have gloves or a set of pliers, cause the plug will be hot!!!

5. read the plug. if the plug is:

black and wet: your jetting is too rich

chocolate brown: your jetting is right on!

white and burnt smelling: yr jetting is too lean! upjet now . you might also notice a blistered insulator. this is real bad. you are lucky you haven't hurt your bike worse!
See sheets below for proper plug colors and pictures.

steve

[honda400ex2003]

Plug reading sheets:

http://www.jetsrus.com/FAQs/FAQ_spark_plugs.htm

symptoms of lean and rich jetting:

http://www.jetsrus.com/FAQs/FAQ_jet_kit.htm

Elevation and Temperature changes:
http://www.jetsrus.com/FAQs/FAQ_rejet_elevation_and_temperature.htm

[honda400ex2003]

Old manual:
http://www.sendspace.com/file/wcy9is

New manual:

http://go.redirectingat.com/?id=162...x-400-ex-2.html

Password is: trx400ex400x

Pages for specs on top end: 104, 110, 121 for cylinder, head, and head cover specifically

Torque specs:
400EX Engine Torque Specifications
from the '99-'05 TRX400EX service manual
Maintenance
spark plug -- 13 lbf-ft
valve adjusting hole cap -- 11 lbf-ft
valve adjusting lock nut -- 17 lbf-ft
crankshaft hole cap -- 5.8 lbf-ft
timing hole cap -- 7 lbf-ft
engine oil drain bolt (crankcase) -- 18 lbf-ft
engine oil drain bolt (oil tank) -- 14 lbf-ft
engine oil strainer screen (at oil tank) -- 40 lbf-ft
oil pipe joint flare nut -- 14lbf-ft


Cylinder Head/Valve
cylinder head cover bolt -- 8 lbf-ft
rocker arm shaft -- 20 lbf-ft
intake sub-rocker arm shaft -- 20 lbf-ft
exhaust sub-rocker arm shaft -- 20 lbf-ft
cam sprocket bolt -- 14 lbf-ft
cam tensioner plug -- 2.9 lbf-ft
cylinder head nut -- 33 lbf-ft


Cylinder/Piston
cylinder bolt -- 33 lbf-ft
cylinder stud bolt -- 33 lbf-ft


Clutch/Gearshift Linkage
clutch center lock nut -- 80 lbf-ft
primary drive gear nut -- 65 lbf-ft
gearshift drum stopper arm pivot bolt -- 9 lbf-ft
gearshift spindle return spring -- 17 lbf-ft


Altenator/Starter Clutch
flywheel bolt -- 94 lbf-ft
starter clutch bolt -- 22 lbf-ft
left crankcase cover stud bolt -- 7 lbf-ft
gearshift pedal pinch bolt -- 14 lbf-ft


Crankcase/Transmission/Crankshaft
mainshaft bearing setting plate bolt -- 9 lbf-ft


Lights/Switches
neutral switch -- 9 lbf-ft

[rubbersdown]

This is a nice post, mod should def. sticky this. Maybe it will cut down on some of the 100 daily jetting question posts lol.

[honda400ex2003]

450r carb adaptor information
http://www.exriders.com/vbb/showthread.php?s=&threadid=421133&highlight=adaptor


I stickied it already in post on the second page. it is doubtful that people will go that far back and read through everything but it is good for me as a base guide for any questions that arise. steve

[BenHonda400ex]

Hey I've got a question I live about hmm like 1,100 feet above sea level. I'm running a 155 main and 42 pilot and 2.5 a/f for the winter and it ran great. What do you think I should run for the summer? 165? Or do I really even need to change it out with just full exhaust and air filter no lid? Sorry so many questions! Thanks Bro!

[honda400ex2003]

you would want to go down for the summer usually. if i understand it correctly you are running no lid and a full exhaust now so i would recommend leaving the 155 in for the summer or going down to a 152. that seems a bit low for a summer jet with a full exhaust but running the stock filter will limit it about 2 jet sizes compared to usual with a full exhaust.

I hope i read it right,

also if possible, and no offense to you for posting here but if you could delete your post after i finish your question, I would appreciate it. I would like to keep this clean of posts.

Thanks,
steve

[sheweezy]

so glad you did this...have searched for a lot of these different posts...now its all in one!! thanks again Steve!!

[atvextremerider]

i have a 170 main slip on with a airfilter

[Drfat400ex]

Okay so I have a slip on, and a filter, and I already ordered a 158. I'm planning on getting a headpipe this winter for it but for now if I mod my airbox would that be alright? I'm also running in cold weather.

[spicer669]

that chart is wickid helpful man but it must be diff up here cuz i work at a honda dealer an the stock main for a ex here is a 138 lol so im wonderin how much my 440 is gona be diff from what uve got here in that chart but its a good startin point me thanks again

[99400exdude]

Just for reference for me, i am making a thread with this info on it. It shows where each part of the carb is in effect. now i can just search for my name and find this lol. steve

My jetting suggestions:
http://img121.imageshack.us/img121/2353/newpicture1d.jpg (http://img121.imageshack.us/i/newpicture1d.jpg/)

Jetting placement chart:

are these keihin jets?

[CJM]

are these keihin jets?

Yes, I know this for a fact he doesnt use dynocrap jets

[JOHNDOE83]

Yes, I know this for a fact he doesnt use dynocrap jets

Not saying theres anything wrong with this thread, Im just saying that if your gonna jet you should follow the jetting procedure for tunning the main jet at www.jetsrus.com

Theres lots of stock bore 400exs running 200 size main jets, its best to find out the right way instead of guessing or assuming jet size.