Pilot jet orifice size

hovel

ol' stupid
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First time poster, long time enthusiast. Working on '74 TX 650, undoing the work of squirrels.
Is there a chart that lists the orifice diameter for Mikuni BS30/96 type pilot jets ? I found a main jet size chart, can't nail the pilots for the life of me. Can anyone help ? Thanks.
 
Welcome here is a chart 5Twins made up.
upload_2020-6-16_8-6-24.png
 
Thanks GLJ but I've seen it and it doesn't tell me the orifice diameter of the pilots nor the mains for that matter.
 
Most jets I've worked with have jet numbers that represent the orifice size in tens of microns.

Ex: A #35 pilot jet will have an orifice size of 0.35mm (0.014")...
 
YES ! That will work 2M. I was looking for a chart but if I have the equation/formula, we don't need no stinkin' charts. Big thanks.
 
That's one of the reasons you can't compare dynojet Jets to mikuni Jets based on their numbers because dynojet uses an actual diameter in mikuni uses flow rate if I remember correctly just like you said
 
I also try and only use genuine mikuni Chad said don't trust most aftermarket ones although I have had decent luck with EBC.

Results have been all over the place with the unbranded Chinese Jets that come in super cheap aftermarket knock off carbs
 
I have increased the thru hole size in genuine Mikuni BS38 main jets only approx .003" by hand drilling. That was easy and just a little more than a "clean up".
I used both lighting & magnification to inspect for burrs. That carb set bench tests (driveway runs) well so far and two short test rides.
I think that is better than buying aftermarket jets.
 

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