jetting

[dannyboy20]

ok the 42 is in along with the 155. Now when i start it it will idle for 10 seconds and die unless i give it gas. It also did this before with the stock pilot. I even played with the idle screw a little bit. But it still wont idle. Any suggestions ???

[hondarider2006]

how many turns out are you on the mixture screw?? Trying going with 2-2 1/2

[dannyboy20]

havent touched it. I was gonn ask if i should adjust that. Were is that located on the carb ?

[linkindust313]

does it seem to run pretty good with the 42 pilot and 155 main? i am thinkin about doin that to mine this weekend. puttin a 42 pilot and either a 152 or 155 main in. i have the airbox lid removed with a yosh pipe and k&n filter. i also have a hot cams stage 1 cam and port and polish done

[dannyboy20]

i really dont no yet i havent ridden it with these settings. Still tryong to find out about the air/fuel screw.

[hondarider2006]

the mixture screw is the little screw on the bottem of the carb. I think its bronze in color. Take the carb off, lightly screw it all the way in, and turn it 2 1/2 turns out. that should do the trick;) I think right now....its at about 3 turns out which it to much.

[dannyboy20]

i have to remove the carb to adjust the screw ?

[hondarider2006]

its the easiest way to, but you can do it w/ the carb on. It will just take a short stubb flat head screw driver. Also make sure your turning it in, and not out;)

[dannyboy20]

ok so all the way in and the 2 1/2 turns out. What exactly does this adjust ?

[dannyboy20]

ok i turned the screw in until i felt good tension and then 2 1/2 turns out. Now i have a weird odor when the quad is idling.Is this from the scew adjustment ?

[hondarider2006]

that odor could be from it being to rich. Also let it idle for a while, and look at the headers, if they turn red than you are too lean, but at 2 1/2 turns out you should be fine.

[JP400ex]

I don't think that the headers being cherry read means your too lean. Mine did that when I got the bike and the guy who had it before me had a 200 main jet in and i know that wasn't lean. My problem is now im trying to get my jet size down to where everyone is saying it should be at and it just seems to run lean (pops after i stab the throttle) I have a 185 main jet in now and it runs pretty decent but is a little rich when the throttle is full open. I picked up a couple more jets today and am going to lower the jet size and change the clip on my needle to the 4th spot.

[dannyboy20]

running rich is better than running lean correct ?

[F-16Guy]

Originally posted by JP400ex
I don't think that the headers being cherry read means your too lean. Mine did that when I got the bike and the guy who had it before me had a 200 main jet in and i know that wasn't lean.
I can't believe your bike is lean with a 42 pilot. Try opening your fuel screw a quarter turn at a time more, don't go higher than a 170 on the main, I prefer the needle in stock or one groove down (richer) position, and check your intake tract for leaks. The popping during deceleration indicates a lean idle circuit. You'd really have to do some work on a 400ex to require a 185 main, let alone a 200. I think you'd see a lot of HP gain by going down quite a bit on your main jet size. If you're lean with a 42 pilot and a 185 main, I'd bet you have an air leak somewhere.

[JP400ex]

Originally posted by F-16Guy
I can't believe your bike is lean with a 42 pilot. Try opening your fuel screw a quarter turn at a time more, don't go higher than a 170 on the main, I prefer the needle in stock or one groove down (richer) position, and check your intake tract for leaks. The popping during deceleration indicates a lean idle circuit. You'd really have to do some work on a 400ex to require a 185 main, let alone a 200. I think you'd see a lot of HP gain by going down quite a bit on your main jet size. If you're lean with a 42 pilot and a 185 main, I'd bet you have an air leak somewhere.

How would i check for an air leak???

Also, I took this video of it running tonight. Its around 5mb so right click and do a "Save As"

http://parsons.dynu.com/400ex/416run.avi