Another round of tuning tonight. First, I ensured no air leaks between the carb and engine... using the starting fluid trick. No leaks detected.
Next I unbolted the carb and rotated it so I could pop the bowl off (after I drained it). I checked the mixture screw... cause it's darn hard to reach with the carb in place... and it was just past 2 turns out... and still lean. I set it back to 1.5 turns out.
Next I pulled the pilot jet. I thought it was a #38... but am not so sure. The stamped # on the jet looks like a 33, but I assumed the second digit was a bad stamp and the 3 was really an 8. Anyway... I checked it using my #'ed drill bits to gauge it's size. It was definitely smaller than .38mm. Maybe it is a #33?? So I easily got the #80 bit through by hand then drilled it up to a #79 (.0145"/.368mm). I stopped there since I didn't want to over-do it. Back together it all went and I fired it up. It definitely idled better. Not so much popping on decel. I played with mixture screw and just past 2 turns out I hit a sweet spot. The engine settled to a nice idle (after minor idle screw adjustment), reved well, no snaps or poping, and the idle returned right back to where it was set without hanging. Very good.
I pumped up the tires and grabbed my helmet... while there was still daylight (my headlight is still off)... and off I went. Happy to say all the gears work, and the clutch too. Speedo feels like it's reading a tad high... pretty common. At just the right speed/rpm... my gas tank starts to buzz. And i don't have any plastics on the bike... just the bare tank. It stopped if I squeezed it between my legs. Okay... at least I found the source of the buzz. Then at a faster speed I could feel the front wheel. I fear it may be out-of-round. I'm getting a weird vibe. Perhaps just the tire and not the rim. Guess I need to check that closer.
Still some more tuning to do after I put a few more miles on it to get a good plug read. I probably should up-size the pilot one more (a true .38mm sounds like it would be perfect)... since I'm past 2 turns out on the mixture screw. But first, I think I'll try lifting the carb needle up a notch to increase midrange fueling. Felt a little sluggish there... not quite eager to rev. First rule of carb tuning... one change at a time!
Cheers!