Ok - so I broke down tonight and bought a new compression tester (to get the required 12 mm adapter). The result: 151 psi consistently - factory spec....so I can now rule out compression.....Did a lot of reading today on Mikuni carbs and carb 101 in general. Now have a MUCH better understanding of how the various circuits work and interface with one another. More and more convinced my problem is the pilot circuit....mixture screw......Tomorrow will confirm correct bowl fuel level and also will pull the pilot screw again. It does have a tip but not sure if this is supposed to be a sharp tip? Please see ATTACHMENT pic of spark plug (white electrode) looks lean to me....and also pic of phantom "mystery holes" in head to right of exhaust manifold....Also gonna pull the inlet manifold to check O-rings and boot tomorrow......May move jet needle clip down one position to effectively open needle jet a bit to see if this helps the issue from idle to 1/4 to 1/3 throttle......thanks for any feedback.....
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