Suzuki Central Forum banner

1 - 20 of 41 Posts

·
Administrator
Joined
·
12,453 Posts
Discussion Starter · #1 ·
Well here's one of them How-To's we've been talking about. Once I put the pipe on the kids quad I knew I'd need to re-jet.
Ideally you'd buy a jet kit that would come with an assortment of jets plus an adjustable needle. I had quite a few jets and the needle from my quad (now has an FCR) so I figured I could make it work.
Jet sizes, fuel screw position, needle info should all be researched for your individual machine.

Here we go.........

As it sits at the beginning

Let's get rid of the snorkle. For us here in sunny California we don't see much mud and water so there's really no point in keeping this obvious restriction!

It can be done without removing any plastics and the tank but why fight through all that stuff. First I removed the side plastics, the tank plastic and then the tank.
Way better this way.

Now I can get to the top of the carb easily to replace the stock needle with the after-market adjustable needle.
Remove the two phillips head screws and take the diaphragm cover off. There's a big 'ol spring in there that should come out with it.
Now gently pull up on the diaphragm and remove it from the carb.


You will need to use some needle nose pliers to get down inside there and pull up on the plastic holder that holds the needle in. It's kind of held in with notches, don't be scared, just grab it and pull it out. Now carefully remove the needle keeping track of everything.
In this picture you can see the stock needle, the aftermarket needle and the holders for both. It came out of my old carb so all the washers are on it already. If you buy a Dynojet kit there will be a drawing of how it should be. I printed the directions off of the internet just in case.

So now the needle goes back into the diaphragm. Careful nothing falls off. You can hold the needle pointing up and slip the diaphragm down over the top then flip it back over. Now slide it back into the carb being careful that the needle goes through the hole that leads to the main jet in the throat of the carb. Make sure the diaphragm is seated right then replace the big 'ol spring and put the cover back on.

Now get an 8mm socket or wrench and remove the bolt holding the black breather box on the right side of the carb. There is a tube leading from the black box to the top of the valve cover. Pull that one off the valve cover and pull the black box through the frame and out of the way. This will allow you to rotate the carb.

Now loosen the hose clamps on both side of the carb. The intake boot and the carb to head boot. Once loose you can rotate the carb so that the bottom is facing the side with the shifter (left).

I removed the screw holding the idle adjustment knob and got that out of the way. This will allow a straight shot to the two screws that the cable partially blocks. It is very important to get a screwdriver that fits the 4 bowl screws just right. They are crappy screws and if somebody has already been into your carb you'll know it. They will either be all butched up or will have been replaced with something better!
Mine look brand new......first in! The first 2 came loose no problem. #3 not so easy so I skipped it for now. #4 came out no problem.
Back to #3. Tried another screwdriver and mangled it pretty good. Now you have some choices. First off you may as well pull the carb all the way out of the boots and through the frame so you can get to the screw.

You can try grabbing it with some pliers, you can cut it off, drill it out or cut a groove into the head with a dremel. The last one is the way I did it (see pic) and I then used a flat head and it came out with no further issues. On the first Z carb I worked on there were 3 I had to groove. At that time I bought a very cheap "dremel like" tool at Harbor Freight. It was a POS but it got the job done and was lke 6 bucks!


OK so we got through that.......it's not so bad when you know what to expect! Now with the screw removed we are into the bowl. The main jet is the one in the middle with the yellowish shield thing around it. The pilot jet is done inside that silver tube and the other is the starter jet (never messed with this one). If I had a 25 pilot jet handy I would put one in now but I don't so maybe next time. The plastic shield on the main jet just kind of snaps on so pull it straight off by hand. Now use a well fitting flat-head screwdriver to remove the main jet. You may want to hold the hex part below it with an 8mm wrench or the whole thing could come out. No big deal if it does, you'll figure it out.

I put a 155 DJ in it and slapped it back together. I did not use the POS screws. Instead I used allen head screws/bolts. Sorry, don't remember the size but you just match to the POS screw and you're fine. I also like to replace the two hose clamp screws on the boots with allen head screws as well.
Now you will need to access the fuel screw. In the last picture there is the head of a phillips screwdriver right where that screw is hiding. The EPA makes Suzuki put a brass plug over it so we can't make too much pollution.
Use a small drill bit (I used a 3/32" with a stop on it) and drill through the plug being very careful to not go to far and hit the soft screw that is hiding in there. The Dynojet kit will come with a bit and a screw to do this with.

Once you have a hole in the plug find a screw that will go in tight and work it out with some pliers.


Now snug that screw down just tight. Do not over tighten it. There is a little tip on the end that can get stuck down there and break off in the carb. This likely turns your carb into junk.
In my case I have a full exhaust, no airbox lid and a K&N filter. I'm going to back it out 3 turns and see how it does.
That's about it....
 

·
Premium Member
Joined
·
5,886 Posts
Great writeup! Could have used this a year ago w/ my stocker. Sticky!!!
 

·
Registered
Joined
·
380 Posts
Good write up spize, could have done with this when I first went at my carb, just a game of trial and error for me!
 

·
Registered
Joined
·
800 Posts
good job spize!
have you ever cut the spring on the top of the carb that holds the diaphragm down? if you trim about 3 coils off of it, it will have better throttle response as it takes less vacuum to lift the slide up.
 

·
Registered
Joined
·
800 Posts
oh and one other thing, that brass plug is not on every carb, its only on the "California" models. both of mine had just a black rubber plug that pulled right out and slid back in afterwords.
 

·
Administrator
Joined
·
12,453 Posts
Discussion Starter · #6 ·
good job spize!
have you ever cut the spring on the top of the carb that holds the diaphragm down? if you trim about 3 coils off of it, it will have better throttle response as it takes less vacuum to lift the slide up.
Never heard of doing that one..........
As for the plug on the fuel screw, are you sure about that? I thought they all had it. One more thing to get screwed for here in Kalifornia.
 

·
Registered
Joined
·
2,286 Posts
Good write up spize..very helpful. Pretty sure the brass plug is in them all...or atleast supposed to be. I bought mine in Virginia and it had it. Was yours used before you smokeya?
 

·
Registered
Joined
·
1,321 Posts
My 03 had the rubber plug, was sold in ny new.
 

·
Registered
Joined
·
463 Posts
Thanks a lot spize! Looking forward to have DIY's/How to's in a single thread. This would have helped me a lot the first time I rejetted my wheeler. Also, my Dynojet kit did not have a bit for removing the plug. Also, my quad did not have any plug, and neither did my last z. Both were bought from the same dealer in MN. Both were 04's.

After I rejetted my carb the first time, I had a similar problem with those stupid brass screws and replace with stainless. I ended up drilling out two, just enough for the carb bowl to come off, then i just unscrewed the studs with my fingers. I bought 8 stainless screws for replacement (it only takes 4) but after rejetting many times, and have a friend help out on the wheeler who loves to over tighten things, I have used up my spares. Next time I will try to find a hex screw that would be the same threads to avoid stripping of the bolts. The main reason I have had problems is because I don't take my carb off everytime I need to rejet. I loosen the boots and twist the carb, which makes some angles for the bowl screws kinda crazy.

This should take care of most questions about rejetting. THanks again!
 

·
Registered
Joined
·
800 Posts
My 03 i bought new and it had the rubber plug, then my wifes 04 i bought used but was bone stock and it had the rubber plug when i jetted it.
 

·
Registered
Joined
·
1,410 Posts
good job spize!
have you ever cut the spring on the top of the carb that holds the diaphragm down? if you trim about 3 coils off of it, it will have better throttle response as it takes less vacuum to lift the slide up.
Does cutting the spring really work? Also, i have heard that drilling holes in the slide can help as well..
 

·
Registered
Joined
·
463 Posts
Both those mods sound kind of scary. If it didn't work out, you would probably end up buying a new carb for parts. I haven't heard of these mods being done before, but maybe they work, just never seen it done.
 

·
Registered
Joined
·
1,410 Posts
I have heard of cutting the spring before.. I think i'm going to try it because it helps a little with throttle hesitation, especially down low.. From what i've heard it's a pretty noticable difference
 

·
Registered
Joined
·
800 Posts
i believe the team alba jet kit tells you to do it, and ive read somewhere on here that its been done before with good outcome, i have not done it to either of my ltz's, but i had an 04 honda VTX 1300 cruiser that i jetted after a set of vance and hines pipes and cut the spring on that vacuum carb to give it better responce and it worked great.
 

·
Registered
Joined
·
463 Posts
Sounds interesting, and I guess it makes sense. I would be willing to do it if I knew others who had done it. I suppose if Alba has it in their instructions it must be helpful. Hopefully someone who has done this to the stock carb will give some advice.
 

·
Administrator
Joined
·
12,453 Posts
Discussion Starter · #16 ·
just kind of surprising that it's never been brought up here before........at least not that I've seen.
 

·
Registered
Joined
·
1,410 Posts
When i return home in a couple days i am going to try it.. I'll let you guys know how it works out..
 

·
Registered
Joined
·
800 Posts
1 - 20 of 41 Posts
Top