New exhaust, need jetting help Please!

[ledofthezep]

Hey all,
I'm going to go crazy here before long...just installed a full WB exhaust with the e-series silencer. It's an '01 400ex and it was running great in stock trim before I installed the pipe. I just can't getting the jetting correct(I believe it's the jetting anyway). I've tried stock/152/155/160 mains and none have helped. It revs ok up to half throttle & then it starts to pop & falls on it's face. Plug looks a bit rich. I took it to the local stealer yesterday & asked them, per their advise I tried dropping the needle down a notch(boy isn't that fun!) & now it's worse than before, runs like crap from low to mid & still craps out worse at mid throttle. I plan on trying to move the needle up a notch from stock & will see what that does. I haven't adjusted the pilot since it runs fine up to mid throttle. I'm running the stock filter(is clean) and removing the air box does not have any effect of the performance. I currently have in the 155 main, it seems to not crap out as bad as the others I tried, but it still falls on its face after mid throttle. Almost seems electrical, but I'm not sure. Why can't the EX be as easy to work on as my banshee?:blah: hehe Any help would be greatly appreciated. Thnx in advance. ;)

LedoftheZep

[Bad Habit]

Brandon,

When you took the stock main out, did the needle jet holder come out with it? That is the tube that the main threads into and the needle slides up and down in. I've had mine come out before, instead of the main unthreading from the tube, the tube unthreads from the needle jet. Just a thought, but there is a locknut on the tube that positions it. It is possible to have it adjusted down too far, which will bring the needle taper out of the main sooner, which would in some sense be like having a much larger main.

Just something to look at maybe. Jetting can be a, umm, character building experience. :huh

Dan

[ledofthezep]

Jetting can be a, umm, character building experience.

You aren't kidding either!:mad: :p

I am sure I got the main in right, withought a doubt. I also tried adjusting that locknut also. I tried it a couple turns in and also a couple turns out from stock position & it made no difference. I'll just have to keep tinkering with it, I'm bound to get it figured out sometime. But I was planning on taking it to the dunes with me this weekend, if I can't get it running right I'll probably just leave the durn thing at home until I can get it running good. I doubt my local stealer could have it in & out by Thursday.:confused: I dunno...Thanks for the reply though, and again for the stuff!;)

[digitalsorrow4]

try lowering the clip to RAISE the needle to let more air in to compensate for the added fuel also try to run a high flow air filter if you aren't already UNI makes a good foam filter.Give that a shot lower the clip to the 3rd postion from the bottom with the 155 main.that should be close.Did you change the piolt jet?

[JOEX]

Originally posted by digitalsorrow4
try lowering the clip to RAISE the needle to let more air in to compensate for the added fuel also try to run a high flow air filter if you aren't already UNI makes a good foam filter.Give that a shot lower the clip to the 3rd postion from the bottom with the 155 main.that should be close.Did you change the piolt jet?
I belive lowering the clip which raises the needle will allow more fuel in to richen the circuit.

[ledofthezep]

I plan on raising the needle just to see what it does, heck I'm up for trying anything. I am going to get a new filter, but not at this time due to my financial situation. I also have not adjusted the pilot, may try a 42 pilot, but it was doing ok from idle to mid so I figured the pilot isn't too far off.:confused: I'll have to tinker with it some more whenever I get time. I foresee some late nights this week trying to get that durn thing going before Thursday!:mad:

[cals400ex]

if your using the stock needle and keihin jets, the clip should work best in the stock 3rd position or in the 4th position. i run mine in the 4th position with good luck. i definately would NOT raise your clip up to the 2nd position. i would make sure the carb is clean and make sure you don't have an air leak anywhere.

[ledofthezep]

Thanks for the input Cals400ex!;) I'm pretty sure there's no leaks, definately something to check though. The needle is currently on the 3rd down I believe, or one lower than stock....made it worse than before, now crapping out from idle to half, then dying at mid-WOT.

[cals400ex]

are you running a jet kit?? just wondering because the needle clip location on a stock needle is in the middle or 3rd position.

[James Parent]

edit:

ops

[ledofthezep]

Well I got it figured out, zephead400ex & I spent about 5hrs working on it last night. You all are going to laugh! :p I had to go with the 155main, dropped down just bit. I adjusted it down using the that locknut, just a couple threads lower than stock. Needle is now in stock position. Ultimately; it help's to not have the choke on...:rolleyes: Yes, I'm a jackass.:blah: All is well now, it's alive & running damn good.:devil:

[cals400ex]

Originally posted by ledofthezep
Well I got it figured out, zephead400ex & I spent about 5hrs working on it last night. You all are going to laugh! :p I had to go with the 155main, dropped down just bit. I adjusted it down using the that locknut, just a couple threads lower than stock. Needle is now in stock position. Ultimately; it help's to not have the choke on...:rolleyes: Yes, I'm a jackass.:blah: All is well now, it's alive & running damn good.:devil:


i was going to mention that but there were two reasons why i didn't:
1. my bike will act up in the all of the gears, not just 5th when i have the choke 1/2 way on. it may be more noticable in 5th, but the power won't be there even in the lower gears.
2. everyone gets flamed for mentioning that. when i suggest that or making sure your run switch is on i get something along the lines of "no the choke isn't on and the run switch is on, i am not a dumbass." i am not trying to be mean, but just trying to keep it simple first.

glad you figured it out. cal

[zephead400ex]

Originally posted by cals400ex
i was going to mention that but there were two reasons why i didn't:
1. my bike will act up in the all of the gears, not just 5th when i have the choke 1/2 way on. it may be more noticable in 5th, but the power won't be there even in the lower gears.
2. everyone gets flamed for mentioning that. when i suggest that or making sure your run switch is on i get something along the lines of "no the choke isn't on and the run switch is on, i am not a dumbass." i am not trying to be mean, but just trying to keep it simple first.

glad you figured it out. cal

haha, thats about right Cal. When dude told me that he had the choke out the whole time, I called him a dumbass and continued to laugh at him most of the evening. Them Yamaha boys don't need to be working on them Honda's! haha!

[ledofthezep]

LMAO, I know what ya mean cal...and being the yamaha boy that I am,...I'm not used to working on 4strokes. It's not even that though, I just got my panties in a bunch & didn't pay attention.
Live & Learn I guess .hehe :D

But if anyone needs their carb rejetted or the needle adjusted, let me know. I think I could do it in my sleep now!:p

[James Parent]

haha i think we pass

[zephead400ex]

Originally posted by ledofthezep
...But if anyone needs their carb rejetted or the needle adjusted, let me know. I think I could do it in my sleep now!:p

haha, that ain't no sh*t!:D

[Bad Habit]

It seems like I remember someone asking about the choke in a pm or something. ;)

Cool dude, I'm glad you got that mofo figured out finally. Now go rip some chit up! :macho


Later
Dan

[ledofthezep]

It seems like I remember someone asking about the choke in a pm or something. ;)
:D Yepper, ya asked if the choke got stuck enguaged or something like that. I just 'figured' I knew it wasn't...but I got my head stuck in my arse & thought that when the choke was actually on, that it was off & when it was off that it was actually on. Good thing zephead was there to call me a jackass, chances are I'd still be tinkering with the durn thing. :blah: Just goes to show what lack of attention will get ya; but on the bright side, I can go through an EX carb if ever needed.;)