Prolific Poster Award
Join Date: Sep 2004
Location: Coventry, CT, USA
The caps are there because the feds don't want you messing with the idle screws... Leave them off.
On more than one occasion when my bike has started to idle low, and I know I set it up otherwise, I have taken the air filter out and cleaned the bead of gunk that builds up around the butterfly valves in the throttle bodies thanks to E10 gas (I say thanks to the E10, because I had my bike for several years before this stuff was everywhere and never had this happen). You can use a rag soaked in carb cleaner.
The bead of goo restricts the air flow when the throttle is closed (idle). You probably just swept the dirt under the rug by cracking the air bleed open to compensate. This may not be your situation here, but it has been mine on occasion. Worth having a look.
Dan. "Painfully mistaking my big talk for the truth" Samantha Fish.
2003 ST4s (The Truck)
1995 916 (Junk Yard Dog)