Another pilot problem

So I have the adjustable pilot and all the sudden can't get it right.

Bike has never given me this problem but now as soon as I turn the choke off it dies. I know that means adjust your pilot so I did.

With the choke on it will stay running so I adjust the screw out (left) to up the rpm and it does...then as soon as the choke is off back to nothing bogs a second and then dies, even if the pilot is all the way out. Think I need to pull and clean? I'm suppose to be riding in 40 minutes and I'm late! I think I would rather just pick up a new pilot on the way what size do I need?:thumbsup:

Edited by r6speed

UPDATE: pulled out the pilot and the main just for good measure and they both looked good, cleaned them up and put them back in, still same problem, seems to be a bit better but not by much. Now it will kind of idle for a little longer and ride a little better until I let out of the gas, pull in the clutch and it can't hold its idle it dies every time...and we all know how fun they are to start when they do things like that!!! yay!!

So now what? I already missed my riding trip so I guess I will be working on it all day. What should I do now?

P.S. after taking the carb apart and taking apart the throttle and all on the carb the throttle no longer "snaps" back. I took it back apart and made sure I got the plastic washer thing back in and the spring was tight but still no snap...what a bad day

EDIT: Well no responses...guess I'm goin for the needle clip and hoping for the best. Its Sunday and I can't even get a pilot jet a different size anyways so can't even try that.

Edited by r6speed

Decided to go ahaid and try getting a new pilot even though it used to run fine with this one. Got a 48 and its completely different! Not even the same threads and it has holes in it and such unlike my original. Not same width or length either. This is suppose to be the one but obviously not...what did I do how did I get this totally different jet (came from yamaha shop). I'm not even attempting putting it in.th_jetsstockand48.jpg

UPDATE:

I finally broke down and took the whole carb out. In the process I somehow lost the little ?plunger rod? that goes into the accelerator...what exactly is that called so I know what to ask for?

Anyways took it all apart and it actually all looks really good, figure I will clean it anyways and maybe take it with me to the yamaha shop, then probably to a local bike mechanic that actually knows something and maybe have him go through it and be sure nothing is wrong and try again I guess...

I know there are a ton of threads about this kind of thing but I tried all the usual solutions...really need some help here, any would be greatly appreciated.

Edited by r6speed

What model and year is your bike?

99 YZF 400

Sorry I don't know why I didn't put that in there...

UPDATE: Also the numbers on the carb above the float boal read 5BE1 and this does have the hot start on it. I just started reading into that because I noticed the boot came off the intake line going to the hot start knob...I'm pretty sure I probably did that while taking out the carb and probably was hooked up fine before and has nothing to do with the problems...who knows though I will definately keep it in mind

Edited by r6speed

The shorter brass item in your picture is a pilot jet. The longer brass item is a pilot screw. Two different things. Be sure the pilot jet matches the one from your carb, as there is a late and early type, and I'm pretty sure the 400 takes the early one.

The accel pump rod is PN 5BE-14379-01-00 and is illustrated as item #39 in the parts fiche. The book calls it a "starter rod".

The shorter brass item in your picture is a pilot jet. The longer brass item is a pilot screw. Two different things. Be sure the pilot jet matches the one from your carb, as there is a late and early type, and I'm pretty sure the 400 takes the early one.

The accel pump rod is PN 5BE-14379-01-00 and is illustrated as item #39 in the parts fiche. The book calls it a "starter rod".

Ok great thank you I needed that info...its the "screw" and "jet" that got me mixed up :thumbsup:

Well I pulled the "pilot JET" and it is not like the new one I got either. It is much much shorter so I am guessing the new one is the early model and mine is the late model? I know the guy was saying something about 21 series and 22 series? Which do I need?

My current pilot JET is a 45 and I am thinking I will go to a 48....think that is wise or stick with the 45 (remember it used to run great...maybe a couple too many pops on decel though so I think 48)

My other jet (which is this?) is a 19

My main is a 175 for 500' elevation which is what I want

I'm pretty sure the exhaust is stock on this but it sure sounds beefy so I could be wrong. These are the jets that where in it when I bought it...switched the 175 every once in a while when changing elevations...other than that always ran great.

Thanks again for the help

The Type 21 pilot looks like this one:

http://i267.photobucket.com/albums/ii315/oldernYZer/PJClose.jpg?t=1269062689

Note the threads are on the larger diameter section. On the Type 22, the threads are on the smaller diameter section.

Don't know what you're talking about as to a #19 jet.

Ok Great, looks like I do in fact have the 21. Now hopefully I can find that sarter rod in town :thumbsup:

Here is a picture of the jet 19 I'm talking about. its just left of the main in the picture

th_underfloatboal.jpg Its size 19 but what jet is it? Just figure I might as well learn as much about this carb while I got it off.

The jet in your picture is the starter jet, which feeds the cold enrichment ("choke") circuit. It should be a 65 from the factory, not a 19. If the bike cold starts alright, don't concern yourself with it.

huh ok, wierd its a 19 thats a huge difference but it cold starts just fine. So I ended up getting the same pilot jet I have (45) just a new one. The guy said if it ran fine before why change it...makes sense. Also said he thinks I will foul plugs with a 48.

So I put it in and got the bike all back together and bam 0-1/4 throttle was great with screw at about 1 and 1/2 turns out and idles like normal again! YAY!

One problem though...after the 1/4 of throttle it seems to want to cut out for a second and not as responsive in the mid range...not real bad ( I would ride it as it is now atleast) but enough to mess me up.

I will keep playing with it I guess

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