Carb Jetting Guide

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Somebody, please, feel free to use these picks. save em and upload em, and fix the posts.. lol or make a new one?

I thought about combining all the carb related threads, removing/dissasembly, cleaning, re-jetting, etc etc, and all the usefull questions with answers etc into one sorta master thread. (theres only about 5-6-7 threads about it, wouldnt be too bad to do. however, its kinda redundant.

speaking of redundancy, some of these picks are sorta, redundant. but I was trying to get everything in thier, different angles and distances etc etc. (And this is a cut down selection of the picks I took.. not bad for cell phn pickies eh? lol)

anyways, heres a good collection of picks I took this evening while ripping my carb out and apart. if there needs to be more, or of other things/aspects etc let me know. Im taking it to work with me tommorrow to rebuild since its dead as hell at work.. lol

Pickies!!

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Choke in (Off??)
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Choke out (On?? this is of particular interest to me. as you can see, the shaft is bent to crap cuz I had problems with it. I pulled it out, to the RUN spot, thinkin I had pulled it to the start. and then it was wedged n such. at least the rebuild kit has what lookes like a whole new end and rubber for this. does this look right for CHOKED position???)

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Choked/on/start postion.. angle 2:
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Looks like all sorts of crap n dried crud in my float bowl:
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I found the perfect screw driver to get those screws out.. no problems what-so-ever.. slightly smaller than a typical star head.
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All apart.. not too sure how it came apart.. some of it shot off n bounced off my nogging when I released the spring tension.. think I found all the parts though...
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Included with the little plastic thingy from the float bowl that sits on the Main jet.
what is that for? heard mention of some kit, (Dynajet??) says to remove n discard. can that thing just be ditched? I wonder if it was in thier properly and perhaps messing with the way she ran some.. ??
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Top needle: Came in rebuild kit
Middle: came outta my carb
Bottom: Out of DynaJet kit (Stage 1)

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note the DnaJet needle is shorter. as in set on the 1st/top position, it would be the same as the 2nd or 3 of the other two, tip wise.
it seems to me to be wider at the top, but tappers quicker at the bottom.
I suspect it would provide more fuel quicker and sooner, but less overall WHEN USED WITH SAME JETS. I dunno.. havent quite wrapped my head around it all yet.

and feel free to go to the album they're sourced from.. lol
Album link thingy... (No idea where this will take you, in theory to the album with these picks.. lol
http://s21.photobucket.com/albums/b256/Lynx_Genisys/Mobile Uploads/
 
thats a weird design carb is it stock? my throttle cable hooked to the carb on the side. And dang clean that carb bowl lol
 
thats a weird design carb is it stock? my throttle cable hooked to the carb on the side. And dang clean that carb bowl lol

haha.. ya, for sure, it'll all be nice n clean by time Im done work tommorrow. buddy from work is also bringing his "Carb cleaning kit" :D

As for the cable. When I was looking into ordering a twist throttle, I discovered theres two variations or so of the carb/warrior linkage. Yes my carb is stock. (On a side note, alot of other people with other brands/makes of machines/atvs/bikes switch to our carb as a desirable upgrade... some people sell it in kit form!!)

The ealier ones had a dual cable going into the carb, (It splits under the fuel tank,) and the later warriors had only one cable.
Or at least thats the way I understood it. Not sure when/what year the change came about.

on a side note, I just found this:

http://www.mikuni.com/pdf/hsr_tuningmanual_021003.pdf

I was trying to look up the warriors mikuni carb. This one is somewhat similar but not the same.

Everything I come across for mikuni carb stuff seems to be Harley davidson related, or compared to kinda thing.

HOWEVER:
For those that can read between the lines, and adapt thier thinking, and understand the basics, there is a wealth of information there to be gleaned when it comes to tuning.

soo many tips and key points about testing, tunning the carbs, jet selections, how to test and select.

If you follow and understand, You can probably set your carb within one jet size on the first go around, even for a basic warrior carb noob like me.

I now know and understand, that a large part of my problem is very much likely the choke seal is buggered up, which makes perfect sense with the history of my machine. I need to correct that issue, adjust everything, then re-test. Likely need to move my needle and she should be good to go. I may need to change DOWN one main jet size as well.

A little more test n tune, and sparkplug reading, and she should be running quicker n snappier than a scalded cat on speed! (Cant remember who said that.. "..now she runs like a scalded cat.." lmao. I loved that! lol

anyways. Im gona extract and adapt a bit of the info from that link and add it into the jetting guide.. it makes things make so much more sense, or at least i nmy mind anyhow. Extra info never hurts. and say the same thing 20 times in a different way each time, different variations and wording will make sense to different people. IE: ME!!! MUahahaha!!
 
DUDE, thanks for the pics. I'll have to gather all the info and make a master thread again. THANKS!!
 
2 more picks today from when I ripped it apart at work

the carb basicaly stripped down on the float end (The pilot jet is still in there, but meh.)

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and the tidbits that came off of it.
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now that Ive had it apart, starred at it, played with it, figured out what passages run to where and how n when, I got this thing pretty well figured out!
It isnt scary at all anymore!! :D

I did strip the head off the little brass piece for where the fuel enters the float bowl, but meh, its inconsequential.

also, I ran and grabbed a 147.5 jet from the dealer.

I wanted a 150 as well, but they didnt have one. I wwhish it was the other way around, so I could start richer and go leaner, but meh.

considering my machine has exauhst, K&N filter, and stage1 hotcam, its kinda scary that its still setup on all stock jets..

I suppose the recently developing backfires where trying to tell me something??? lol

oh well. she'll be all cleaned and rebuilt by tommorrow night.
If I didnt just undergo 6hours of driving after work to go pick up the lil bro in law and his buddy who got rained out down where they were working for the summer, I woulda had back together and in tonight.. meh.

at least if I want the other jet, they can have it ordered and in within a day, but i said screw it, Im almost broke, even though its only 5$ figured I may as well just try the 147.5 n see how she does n go from there.

oddly enough, reading the plug, it seemed almost borderline rich. of course the choke issue was there as well. And Im wondering if maybe the plug isnt just a bit too hot for it.

ah well.. I'll get her over the next week or two. test and cahnge it each day and check her.
 
DUDE, thanks for the pics. I'll have to gather all the info and make a master thread again. THANKS!!

I have some tips and info I want to include as well. mainly on diagnosing and such to make things easier n all to decipher. I woulda had it posted up tonight, but had to attend to other things.. now after working 10 hrs and driving for 6, im gona go have a beer, shower smoke and hit the pillow though. i should get it up tommorrow though.
 
I could, but just thought it would be simpler to keep it all together an collectit one place.. lol

pretty much just a copy n paste anyhow from a set of instructions from Mikuni on carb tunnig n all.

Its actualy for a slightly different, but similar carb, but all the principals etc are the same.

I guess I will.. but for the moment, Im putting my carb back together and then onto the quad! :D

I just had to come check something.. seems to be alot of extra parts in my rebuild kit.. little things like mini o-rings n stuff.. lol im sure they should go someplace.. and a totaly random spring... ACK!
 
grrr.. i cant get this thing tuned properly...

Im tempted to just take it in and get it done. Or take it to mech and get him to see what its doin n what he suggests.

So I got it back together, with one size bigger main jet.
I raised the needle one slot. set the idle mixture.

took her to work the next day, she ran like crap. seemed okay at wide open. so I figured it must be the needles position.

I lowerd the needle.

I recalled reading about the roll off method for testing the main jet.
pin her, wide open, then quickly close the throttle to about the 7/8ths position.
If the engine seems to gain power, its lean, if it hesitates when the throttle is rolled off, then the main jet is too large... Note that a main jet that is far to rich or lean may cause the engine to misfire at full throttle...


well, I did this, and it all seemed to be good. but then I did it a couple of times, and then BAM she just stalled right the hell out, dam near died completely.

Had to feather the **** outta the throttle to keep her running, and then she suddenly picked up again n off we went... straight home.. lol

I tried it a couple more times on the quick rip home and same thing.
If I dont do it, it seems fine..

WTF??

I almost wondered if it wasnt a fuel starvation, like maybe I didnt get the floats set right and shes running out.. is that even possible?? lol

Im gona take her to the shop tommorrow. I'll run her flat out and see if she starves.

I seriously dont know wtf is going on.. I may just splurge and get it tuned by someone that knows what they're doin.. however, Its gonna bug me to no end if I cant figure it out myself.. lol

EDIT:
on all accounts the plug looks good, untill the last time, just the tip an tab are a shade whiteish (lean looking) but the base is sooty.

it has always looked good up until this last change, which is totaly messed, as I went richer with everything...
 
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Found this:

http://www.youtube.com/watch?v=PPpdINqDGdg&feature=related

Note its not a warrior or a quad. Im pretty certain its actualy a 2 stroke.. a gas powerd scooter dealy.. However...
..its fully tunable, top n bottom without changing jets n all that.

The guy uses it to demonstrate rich and lean conditions.
Helped me out a ton!

Im gona keep looking for other demos such as this. Im getting less and less hopeless at this figuring out my carbs jetting.. one youtube vid at a time.. lol
 
Im loving this thread but i have one problem i don't see these pictures your relating to.can anyone let me know how to veiw the pics for the carb jetting on this thread plz thx.
 
2 more picks today from when I ripped it apart at work

the carb basicaly stripped down on the float end (The pilot jet is still in there, but meh.)

201007201332.jpg


and the tidbits that came off of it.
201007201334.jpg


now that Ive had it apart, starred at it, played with it, figured out what passages run to where and how n when, I got this thing pretty well figured out!
It isnt scary at all anymore!! :D

I did strip the head off the little brass piece for where the fuel enters the float bowl, but meh, its inconsequential.

also, I ran and grabbed a 147.5 jet from the dealer.

I wanted a 150 as well, but they didnt have one. I wwhish it was the other way around, so I could start richer and go leaner, but meh.

considering my machine has exauhst, K&N filter, and stage1 hotcam, its kinda scary that its still setup on all stock jets..

I suppose the recently developing backfires where trying to tell me something??? lol

oh well. she'll be all cleaned and rebuilt by tommorrow night.
If I didnt just undergo 6hours of driving after work to go pick up the lil bro in law and his buddy who got rained out down where they were working for the summer, I woulda had back together and in tonight.. meh.

at least if I want the other jet, they can have it ordered and in within a day, but i said screw it, Im almost broke, even though its only 5$ figured I may as well just try the 147.5 n see how she does n go from there.

oddly enough, reading the plug, it seemed almost borderline rich. of course the choke issue was there as well. And Im wondering if maybe the plug isnt just a bit too hot for it.

ah well.. I'll get her over the next week or two. test and cahnge it each day and check her.




I have a q about the rod coming out of the bowl in pic 2. in my 96 carb it's extended like that, in my 2000 carb in pushed down, i tried to pull it up but couldn't, what does that mess mean?
 
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