Lean & Idle Connection?

[Quarteg]

Backstory -
A few years ago on my '86 GL1200 Aspencade I started putting Seafoam in my gas tank and a bit in my crankcase during oil changes and winter sitting. However, every spring it burned so rich my eyes would start watering.

Fast forward to my '94 1500 Aspencade:
Last winter, I was watching the video from our forum leader and he mentioned adding Seafoam as an additive also. Since I knew my bike was going to be in a cold garage all winter I followed this advice.

Last year when I purchased my '94 there was no odor. I add Seafoam and boom! There's that rich smell again.

This also seems to have had an affect on my idle. If you were to listen to it, you would think the timing is off but I'm not sure it is.

I cannot rotate the dial next to the gas tank to make adjustments to see if I can fix the idle.

Is it possible the two are connected? I will not be adding Seafoam in my bike but with one exception; When I changed the oil, I added Seafoam into the crankcase to flush out the old oil before adding new clean oil.