Where can I buy VM22 carb idle jets?

Where can I buy VM22 carb idle jets?  I am looking for a #16 idle jet instead of the #15 provided in my kit.  Any companies that provide these jets?  US if possible for shipping.

I currently am trying main jet 90, idle jets 50 and 15.  The idle circuit just not working for me.  Can't get a decent stable idle.  Choke has to be ON.   1978 KZ650 B2A 

Regards

John
 

Idle jet?  Do you mean PILOT jet?  

Common steps on the pilot jets is 2.5 points.  So there is 15 and 17.5, unless you buy some specialized OEM type jets. 

I doubt the pilot jet size is causing the unstable idle issue.  It's critical to clean the carb bodies and various jet parts carefully.  Set fuel level using the clear tube method.  Perform vacuum sync.  Replace carb rubber boots attached to the head, and make sure the airbox boots are in good shape.  

Thank you.  I appreciate the advise.  My idle circuit has 2 jets in it.  A #50 on top and a longer #15 below it.  This is a VM22ss carb.  Sorry, if I am not using the correct terminology of pilot jet / slow jet / idle jet.  My 1978 KZ650B won't get a nice lopping idle unless I have the carb lever pulled. If carb is pulled halfway, I can adjust the thumb idle center screw from 4rpm down to 2, but she struggles below 1500rpm.  If I close off the choke lever, it dies flat off.  It will die off flat even at 3k rpm.  Won't restart unless the choke is on full or half On.  

My fuel/air mix screw that inserts below the bowls is at 1 1/4 turns out.  I tried various fuel/air mix numbers.  1/2 turns out....sort of same.  1 1/2.....sort of same.  2 1/4 .....sort of same story.  Engine temps reach 220 degrees on all 4 cyl.  Float levels are at 23mm. 

With the choke lever 1/4 to 1/2 ON, I can repeatedly run the bike for 5-10 minutes.  Usually at 2k rpm.  I plug the tank's vacuum tube on cyl2 and use a bottle to feed the fuel.  Standard airbox in use.  Main jet 90.  Carbs cleaned several times.  Not the choke plungers though.  That will be my next step.  New jets and fuel seats in use from a generic carb kit.  

Intake boots are new and tight.  Air box boots also new and sealed well. I haven't tried taking out the K&N air filter in the standard box.  I might try that.  I do one change at a time.

My thinking is the #15 jet needs to be larger from spec, to not need the choke to be on.  Kits I see are all #15s though.  Maybe something is plugged in the plunger choke area.causing this behavior.  Thanks for your advice.


 

You issue appears to be a weak idle mix or fuel starvation at idle .
If the jets are not blocked they are not the problem and it is more likely a blocked drilling or damaged pilot screw.
You should inspect the pilot fuel screws for broken tips which are blocking the pilot outlets.
The screws should have sharp pointed tips and if they are blunt it's likely the remains are stuck in the pilot outlet.


 

I agree with checking the carb bodies for broken off tips of the pilot fuel screws.  Typically, these fuel screws have a drastic effect on running mixture; it's rare to need them open more than 1 full turn.  I'd start at 7/8 of one turn.  Any way you look at it, you don't need larger pilot jets to smooth the idle.  From what you describe, there is a problem, it's not an issue related to the base jetting sizes.

Thank you both for direction.  It keeps me from spinning around.  I agree something is wrong with the normal pilot fuel getting where it needs to go.  The fuel/air mix screws are new from the kit.  I might change back to older ones.  I am sure they are not EOM but another prior kit, though.  It would be interesting to see if that has an impact.

What I did was previously check each jet.  The #50 and #15 for passage.  I also used carb cleaner spraying thru them plus air compressor.  They got thru but now knowing something is not clean, I will spend more time on that.  See if the end is blocked/restricted by the rubber boots when installed on the bike.

I didn't want to take apart the bodies to get at the choke plungers, but probably worth the closer inspection.  My theory is the choke on at 1/4 up is providing fuel.  When I push the choke closed...off goes the motor.  It looks like the choke is the only source for fuel on this girl.  Yeah, I don't want to ride a bike that needs the choke on all the time.  It is hiding a problem.

I have an ultrasonic cleaner that I could put the carbs in.  That seems to clog passageways frequently.  I am thinking of using Berry Chem dip solution on these?  Does Chem-dip damage to parts?  Again, I appreciate the ideas.  3 heads are better than 1.


 

When rebuilding VM's, I remove everything off the carb bodies, then soak the bodies, float bowls, and jets in Berryman's for a few hours.  There is no need to remove the needles from the slides, or break down the choke plungers, but most everything else gets taken apart.  When done, shoot carb cleaner though every passage and make sure it comes out where it's supposed to.  That includes the choke passages both in the carb body, and float bowl.  Put the spray nozzle in the small hole at the base of the choke passage in the carb and shoot.  Spray should come out the choke pickup tube on the bottom of the carb, both on the end of the tube, and crossways on the tube.

These may help...

gsarchive.bwringer.com/bikecliff/images/vm_carb_rebuild.pdf
gsarchive.bwringer.com/cbsaunders/gs/pilot_screw_removal.pdf

wow, great stuff.  I wondered how I could fix a broken off tip. Great article.  When I pull this off, I will be able to see if it is plugged.  And how to pop it out.  
 

I pulled the carbs and striped it down.  First thing I looked for was that fuel/air mix screw.  It was not damaged.  I could see the little point and when turning all the way out, carb spray made it through all 4 carbs nicely.  A relief for me.  I moved on to removing the two double stacked jets.  Clean there too on all 4.  Air compressor spray and carb spray seemed to go places it should.  Same on all 4.  Air vents clean, fuel channels clean.  

I also removed all the choke plungers. Spray through those channels seemed also clean and equal on each.  I would put a little carb spray in the opening and then compressed air to see where it exits.

I did notice on the plungers, that two of the plungers where the white pull caps (#19 part) are missing O rings.  They seal the pull cap and the black top caps (#20).  The other two plungers had very worn useless orings there.  I am replacing them.  The main O rings looked ok on all 4 but if I some I will change them.  So that is all I found.  Not a good answer.

I am thinking of using the old #15 jets although they are tarnished, but I can verify the openings are clear.

So that leaves me with fuel height in the bowls.  Years ago, I made a drain cap with a clear tube connector.  Have to dig around and find it or make a new one.  Measuring 23mm from base won't tell me the correct answer.  

I am going to let this carb sit for a few days and work on some electric tasks.  Thanks for the assistance.


 

I use clear tubing pencil pointed so to speak, screwed into the float bowl drain threads, as a tool for measuring fuel level.  It's effective and cheap.

A question for you regarding air filter, running stock air box and filter, or pods or nothing?  Pilot jets for the vm carbs tend to run in 2.5 increments.  Not attempting to say you need larger ones but the next size would be 17.5.  

As to the #50 jet over top of the pilot jet, I have removed them and left them out without any issue noted in running.  

After a short delay, I got back working on these carbs.  Cleaned them.  Paid a lot of attention on the pilot jet channels.  I would like to find the VM22ss #50 jet that sits on top of the other pilot jet but can't find one to buy.  The opening is clean but that is my only idea.

The use of clear tube fuel level worked perfect.  Thanks. Trimmed it in a V shape and screwed them in.  No leakage on the testing.  I discovered each bowl had different measured heights.  Now I have settings of the floats at 26.5mm for cyl1 and cyl4.  24mm for cyl2 and 3 allowing me to be at 3mm actual fuel level.  

Bike started and idled very well today.  I attribute it to the fuel level Nessism suggested to fix me up.  I also removed my Dyna S ignition and went back to stock points and condenser.  My Dyna S gave be tons of gremlins making ignition shutting off cylinders here and there.  

My only problem left is the choke lever.  It needs to be up 1/2 to stay running at idle.  Engine temps around 190-210 all cylinders.  Fuel/Air mix on this VM22s is at 1 1/4.  If I close the choke, it floods my engine.  Why I don't know.  The result is that I can't restart the bike until it evaporates.  Or kick start it with the throttle open to give it more air.  

I tried the fuel/air screw at 1/8 (nearly closed).  same result.  Screw at 3-4turns out same result.

My  last idea is that #50 jet is restricting it too much to turn of the choke.

I did read one posting the recommend just removing the #50 jet.  Author said it worked fine with or without it.  I might try that next round.