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Omoc
10-19-2010, 12:41 PM
I have an 02 400ex with a fmf procore 4 exhaust, 450r carb, stage 2 hot cam and a rev box. 1st and 2nd gear run fine but when I get on the throttle hard in 3rd it bogs down. 4th and 5th bog as well. Any suggestions on the jet size I should be using??
honda400ex2003
10-19-2010, 01:57 PM
what are you at now. i would say to go down a size or two on your main to something along the lines of a 158 or so with a 48 or 50 pilot at around 2.5 turns out on the f/a screw but i would like to find out what you are at. I would think you are around a 165 judging by some of the others that have gone off of fmfs suggestions and such. leave the needle on the 3rd clip for now. steve
honda400ex2003
10-20-2010, 09:07 PM
guess your not too worried about it? steve
Omoc
10-20-2010, 10:19 PM
Originally posted by honda400ex2003
guess your not too worried about it? steve

No thats not it i just havent had a chance to work on it yet. Im not sure what the jet size is but ill update you. i just bought the bike saturday and havent had it apart yet. i do appreciate the advice.
honda400ex2003
10-21-2010, 10:55 AM
sounds cool I was just messing with you anyway, I figured you were busy, most guys with jetting problems are like: i gotta get this fixed asap i have a big ride coming up or something. lol steve
honda400ex2003
10-21-2010, 10:56 AM
oh and welcome to the site :D steve
Omoc
10-21-2010, 03:56 PM
ok steve here is what im workin with. the guy i bought the bike from was using a 210 in the main jet. I went to a 160 and the bike ran ok. i then went to a 165 and the bike runs much harder. The next size i have is a 190??? i dont really know what to do from here i was thinking a 175 would probably be better. what do you think???
honda400ex2003
10-21-2010, 04:08 PM
next size would be a 168. then then a 170, 172, 175, 178, 180. there is an extensive amount of jets to choose from. heres some info to help you out:

http://www.exriders.com/vbb/showthread.php?s=&threadid=445695&highlight=jetting+placement

check over the list of jets and such there. I would say that you would be too rich with a 175. I dont think anything over a 170 is needed for you. I am going to bet that the 165 is where you should be at. get a new plug and do a couple of plug chops as per the jetting placement thread. you can also tune your pilot circuit also when doing it. steve