Recently my Monster S4R has developed a minor idle issue. When I am idling the bike it will initially idle fine, but 20 or 30s into idling the bike will begin to seemingly misfire ever so slightly. The engine speed will dip and each misfire is separated by about 5 or 10s. This has caused the engine to stall.
My guess is fouled plugs, though I have noticed no issues at all with power output and how the bike runs when riding. Issues only occur during idling. Does anyone know what this might be caused by? Other suspicions are throttle bodies that need to be balanced and TPS issues. I have put ~1300 miles on the bike since I bought it and had no issues up to this point when this issue began occurring in the last day or two.
TL;DR Bike has an idle issue. I think it may be a misfire. What could the root cause be?