Squashed Pilot Jet in Old Mikuni?

I was rebuilding an old Mikuni TM Flat Slide carb.  It was running fine, but float needle was leaking a bit.


When I took out the pilot jet, it unscrewed, but was stuck in the hole.  I pulled it out with pliers.  It was "compressed" at the upper end (where there is a wide bore and some side holes.  It was compressed like accordion at the side holes.  I replaced it with new jet, but when I screwed it in, the same thing happened to the new one.  Obviously, the tip was not clearing the bottom (top) of the hole.


Anyhow, I figured that it was running fine before, so I removed the squashed end and reinstalled.  I figure the gas metering (jet bore) is done at the bottom end (near screw head).  Bike is apart for other work, and it will be a while before I can test.


Think it will work?  What is purpose of the tip of the pilot jet (with wide bore and holes in side)?



Are you sure you are using the correct jet? JETS.RUS has jet dimensions / applications on their website. If using the correct jet check for obstructions or a deformity in the jet passage. I wouldn't run a crushed jet. The end is where the fuel and air mix.

Keenxxx - Yes - you nailed it.  Wrong style jet was in there.  It was running good though.  I assume I can replace with correct style and same number?

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