And even more stock carb problems

Well Ive searched the forum but cant find anyone with close enough to the same problem to help any.

What is going on is I have a 3x3 mod, rs3 Yoshi pipe, DJ kit, uni filter, 142.5 stock main jet, 25 pilot, 3.5 turns on my idle, and 5th clip down on needle instead of 4th(that was necessary to get rid of a steady throttle surge),and what happens is when I just try to bump the throttle from idle, not rev it up a bunch, the idle will drop and the bike might even stall. But if I just whack the throttle WFO it revs just fine (well i guess fine for a CV carb anyway). It mainly effects me when I am coming up to a 90 degree corner on the street and try to feed it just a little throttle through the corner the bike starts to lunge and stumble but if i give it more gas its alright, and off-road it unrideable because at low speeds and light throttle it will die and in turn I usually fall over.

It does get worse when its hot which burned says that means rich, but if i lean the idle screw out it get worse when cold and hot. I have even had the idle screw all the way in and it would idle and rev fine but the light throttle bog was insane so i ended up with 3.5 turns which seems best I suppose.

But what should I do if anything, I am waiting for TT to get in a shipment of FCR's which I have been waiting oh so patiently for :excuseme:, or go up to a 27.5 pilot, or stock 22.5, I really dont know where to go from here. Thanks in advance for any help, this really is a annoying issue.

It would help if you gave some more info. By the mention of 142.5 Pilot jet and the 5th groove for the clip vs. 4th, I'm assuming you have an S model (vs. SM). Also, you mention "idle screw" 3.5 turns, but I'm guessing you are speaking of the fuel mixture screw. The norm is about 2 to 2.5 turns out with the 25 pilot jet. If that wasn't working for you then something else might be wrong. Also, it would help if we knew if you just did the jetting mod and its performing the way you describe from the beginning, or if you did the mod a while ago, the bike worked fine, but now it's not. If you clear some of those questions up, it will help to narrow in on a suggestion. (it also helps to know your elevation from sea level).

For the S model, from what I've seen here, most people have good results with the 25 pilot jet, 2.5 turns out, 4th groove down on clip (like the instructions). It seems like main jet is either 142.5 or 140 (I have an SM, so I don't pay as much attention to the S main jet size). Since yours isn't working well for you, it could be something went haywire when you did the jetting. Some people remove the wrong jet instead of the correct pilot jet. Some people don't get the slide needle assembly washers/spring/etc in the correct order, or don't seat the white plastic retainer thing all the way in and the needle floats around. Some people loose the little rubber "0" ring that's under the black plastic slide cover, etc. etc. Some people have complained of an off idle bog or stumble that was simply fixed by raising the idle (using the idle screw, not fuel mixture screw).

So let us know some of the missing info so we can offer suggestions, and maybe go thru your carb to double check your assembly.

I hate it when a bike runs like that. Hard to ride smooth. Takes all the enjoyment out of it. Try setting the idle speed where the dip is worst and settng the mixture screw there. Try the 22 pilot. Try the needle back on -4. I could live with a little surge easier than a lurch off idle. Take a look at the float stting too.

It would help if you gave some more info. By the mention of 142.5 Pilot jet and the 5th groove for the clip vs. 4th, I'm assuming you have an S model (vs. SM). Also, you mention "idle screw" 3.5 turns, but I'm guessing you are speaking of the fuel mixture screw. The norm is about 2 to 2.5 turns out with the 25 pilot jet. If that wasn't working for you then something else might be wrong. Also, it would help if we knew if you just did the jetting mod and its performing the way you describe from the beginning, or if you did the mod a while ago, the bike worked fine, but now it's not. If you clear some of those questions up, it will help to narrow in on a suggestion. (it also helps to know your elevation from sea level).

For the S model, from what I've seen here, most people have good results with the 25 pilot jet, 2.5 turns out, 4th groove down on clip (like the instructions). It seems like main jet is either 142.5 or 140 (I have an SM, so I don't pay as much attention to the S main jet size). Since yours isn't working well for you, it could be something went haywire when you did the jetting. Some people remove the wrong jet instead of the correct pilot jet. Some people don't get the slide needle assembly washers/spring/etc in the correct order, or don't seat the white plastic retainer thing all the way in and the needle floats around. Some people loose the little rubber "0" ring that's under the black plastic slide cover, etc. etc. Some people have complained of an off idle bog or stumble that was simply fixed by raising the idle (using the idle screw, not fuel mixture screw).

So let us know some of the missing info so we can offer suggestions, and maybe go thru your carb to double check your assembly.

Yes it is a S not SM. I ride about 500-1000 feet from sea level. the air filter is clean. the float level is 14mm( I think thats in spec). I checked the slide and needle Assembly and all is good and in place. the fuel mixture screw is 3.5 instead of 2.5 turns because that just seems to work the best, but it doesn't really seem to effect anything. the idle is set pretty much as high as I can go before the idle starts hangs high for a few seconds when its coming off throttle.

I followed the instructions from this page, http://www.4strokes.com/tech/suzuki/drz400su.asp, and to began with it was running great, but then I couldn't ride for a while and the jets gummed up on me, I took the carb apart and got everything cleaned up and It developed a couple problems it would have that stumble at the bottom, and also at steady 1/4 throttle doing 35-45mph it had a wicked hesitation that made it unbearable, so my consensus was it was REALLY lean at that part of the throttle and not getting any fuel, so thats when I droped the needle from the 4th to the 5th and it fixed the problem pretty much entirely, but that light throttle stumble was still there. I know if it ran right to began with that it should of ran right after I cleaned the carb but...

Its just confusing because it will idle all day and then you could whack the throttle open and it would rev but then when it idles back down and you just touch the throttle, less that 1/8 of a turn it will do the stumble die trick :excuseme: It actually is really easy to just ride through it but thats only on the street, for off-road it just has to be dealt with. Let me know if you need any more info. Also could it be somewhere else besides the carb settings, i could try a new spark plug in it but the bike only has 900 miles on it so I wouldnt think thats it.

In my opinion, the key item is your mention of the bike running great, then sitting for a long time, then the jets gummed up. My ZX7 Ninja sat for a long time and the same gumming happened. It now has a hesitation when just cracking the throttle like yours. Idles ok, runs strong after you get past the hesitation. I'm pretty sure my problem (and yours) is that the one or some of the internal orifices/holes of the carb are still gummed up. You can remove the jets and clean them, but getting into the little internal passages is an entirely different matter.

I think your mention of the fuel mixture screw "not really affecting anything" and having it turned out to 3.5 coupled with you raising the needle (5th groove) (both items effectively making things richer) both point to some carb orifice/passageway still being gummed up (add in your comment that the bike appeared really lean at that setting, to me almost confirms that an internal fuel passageway is still plugged). I suggest tearing the carb apart removing all removeable jets and needles/whatever, and using lots of carb cleaner and maybe poking thin wire (guitar string) into all the holes and orifices you can find.

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