Join Date: Mar 2010
Location: Lebanon, Pennsylvania, USA
Model: 1984 GL1200 Standard & 1987 GL1200 Interstate
The idle jet came stock at .55mm but it was idling too rich. It is currently approximately 0.30mm. Approximately because I cannot be sure the hole didn't elongate as I drilled it out. I soldered the jet and then increased the size of the jet until I was happy with the idle.
The main jet is a 1.35. Stock was 1.275. I bought a few different sizes and kept increasing the size until I like the acceleration. It takes patience because you also need to contend with the acceleration pump dumping fuel into the carb under heavy acceleration. Turn that back to the lowest setting and get everything running good, then fine tune from there.