It’s alive!
My ’83 Honda GL650 Interstate – with the cleaned and re-jetted carbs (Keihins) installed. The results are good all around.
No, great all around.
The bike pulls noticeably harder than it did before – and (based on two rides so far) seems to run cooler, too. The gauge indicates just past “warm” whereas before it ran noticeably hotter. I attribute this to the richened-up mixture, which I am betting compensates for the leaner mixture it was running before, courtesy of the ethanol-laden “gas” in circulation. 
I upped the main jet from the factory 118 to 120s – and the “slow” jet to 80 from 78. No other deviations from stock. Air screws turned out about 2 turns from lightly seated.
Based on my results, I’d recommend this mod to anyone who has one of these bikes – even if (like mine) it’s completely stock. The early ’80s was 30 years ago – and the gas then is not what “gas” is today. Plus, during the late Carter/early Reagan years, the manufacturers (cars and bikes) often set their products to run lean as a way to squeak past emissions regs. If they were lean then – running 100 percent gas – they are really running lean now, running 90 percent gas and 10 percent ethanol.
Of course, your mileage may vary…
Throw it in the Woods?
Eric, did you calculate, guess, or ask around to determine which jets to use?
Are you going to check MPG change long term as well?
PS – Lauuudy, lookin’ good, and a real CB antenna.
Just a guess!
I went up two numbers from stock – so just a slight step in the “richer” direction. The bike is not modified. It still has the factory air box and air cleaner (no holes drilled, etc.), stock exhaust system, etc. I suspect anything more (richer) would be too much. The bike seems to be very happy now. Certainly, some of that has to be credited to the thorough cleaning I gave the carbs while they were off the bike (my bet is they had not been off the bike since 1983, when the bike was built) but it feels stronger/pulls harder now and – by the gauge – appears to be running about 5-10 degrees cooler.