Good question, since details are lacking.

You may be chasing the wrong parts for the wrong carb.

Jet in bowl is MJ from the side in a main jet holder, or the starter jet (SJ) deep inside the well, if equipped.

I have many Mikuni carbs without the starter jet in the bowl.

cliff
  Good question, since details are lacking.

You may be chasing the wrong parts for the wrong carb.

Jet in bowl is MJ from the side in a main jet holder, or the starter jet (SJ) deep inside the well, if equipped.

I have many Mikuni carbs without the starter jet in the bowl.

cliff
 

Do you have an example of your claim about the lack of starter jet in the bowl automan?

Personally, I have never seen a single cylinder Mikuni-Amal carb (VM style) without the starter jet* in the float bowl.

And since Yamaha used the "VM style" Mikuni carbs on pretty much every two stroke enduro from the late 1960's through the early 1980's, I've never seen a two stroke Yamaha Enduro Mikuni carb without a starter jet in the float bowl that I can recall?  

*some Mikuni "jets" are not replaceable and may even be a calibrated hole drilled directly into the casting itself...

Nor have I seen a Mik. without a pressed in SJ. I actually just noticed, based on this thread.
I have 2 spare bowls here from a Polaris triple sled.

No brass. I'll measure orifice shortly.

cliff

.058" inlet (at the base) .059" outlet (down the well)
Maybe  pix next

imgur.com/N00Mczy

Thanks for verifying.  It's a very easily overlooked jet that can cause all sorts of starting grief when plugged. 

More than a few people have been told about it and "blow it off" for lack of a better term, thinking their carb doesn't have a starter jet in the bowl when it actually does.  Eventually they hopefully figure it out. 

P.S. The only Yamaha VM Mikuni I've seen without a starter jet are the "second" carb on a twin cylinder...  only the main carb has the "starter lever" and a connecting tube to the second carb delivers the extra fuel to the other cylinder.  On these twins, you need to make sure to put the correct float bowl with the starter jet on the main carb.

Took a microscope pix but no dice presenting

imgur.com/a/oaV31en

Anyways, I've not seen jet setter/needle jet threads in anything other than Amal type threads.
Not made for reverse type threads.

cliff

Just thinking back to the likes of RD350 etc being twin cylinder but the choke is only fed off the left bowl & i "think i remember" finding one on a customers bike swapped left for right so puts choke out of action or actualy makes it worse than out of action due to opening airways on both when operated but no added fuel. Maybe someone can confirm that. Possibly snow ski things with multiple cylinders could be the same, just one carb bowl supplying fuel.

Automan wrote:  Anyways, I've not seen jet setter/needle jet threads in anything other than Amal type threads.
Not made for reverse type threads.

There are definitely at least two "jet setter" threads from what I've seen.  Earlier 250/360 has the needle jet (and jet setter) threaded for the Amal/Mikuni round main jet.  Later models had a needle jet (and jet setter) threaded for the Amal/Mikuni 4/042 hex (aka "reverse flow") main jet. 
Even though installing a hex main directly into the needle jet technically has the fuel flowing backwards through a hex main, it became "standard practice".  (Apparently even though the hex main flow is designed and measured with fuel flowing in from threaded end, reversing the flow by installing the hex main with fuel flowing out the threaded end makes very little difference.)

(And yes, jet threads are "English"...  not metric...  a carryover from Mikuni copying the Amal carb design that was never changed.)

Perhaps you need another pair of Polaris carbs Automan? Flange mount. 1972 (399?).
Just taking up space here.

Need nothing. Thanx!
I use small body vm34's on me triple. Bowls back to internal mains(hex) and .022" starter jets with well break.

cliff