2000 R1100RT rough idle

[117257]

54k miles, performing the 6k maintenance today (happy birthday America!), all other maint is up to date. Bike is used regularly, not sitting idle for long periods of time.

I noticed that the idle is choppy (best word I can think of to describe it) as it has been for some time, but it is smooth throughout the range above idle. It has even died on occasion when going to idle after getting off of the interstate, but normally isn't rough enough to die, just not smooth.

Used the Harmonizer to synch the TBs today and set the idle at 1150 rpm, equal vacuum, but the idle is still not as smooth as it should be.
Both cables have about 1mm play, brass screws started at 1.5 turns out, then equalized. The screws were removed and cleaned last time, didn't remove them this time.

Any ideas what could cause this?

Thanks for helping me achieve idle sanity.

[m_stock10506]

I would pull the brass screws again. Spray an O2 safe carb cleaner into the air bypass with the hose at the bottom removed so the excess runs out at the bottom. Then I would put Techron into the gas tank at the listed concentration and run out the tank.

[117257]

Bypass ports must have been plugging. Your suggestion worked great, thanks. Followed up with compressed air.