I have a 2015 XMR 800 that I bought new last Sept. The bike currently has 73 hours and 390 miles. It recently developed a "stumble", for lack of a better explanation, that occurs through out the rpm range but is more prominent around 3500 rpm and more noticeable in low. At 8-10 mph in low holding a constant rpm there is an audible exhaust stumble that can also be felt, almost like a misfire. Plugs look good, vent line from tank is clear, valves have been checked, problem occurs with gas cap on or off. In an unrelated discussion with my local dealer when buying valve cover gaskets, the tech told me about problems he has seen with a sensor on the intake plenum that relates to air fuel mix, and how it is sometimes confused with valve issues. I had never heard of this so I took it with a grain of salt. Has anyone heard of this? Any ideas on what is causing my issue? Thanks in advance.

I have a 2015 XMR 800 that I bought new last Sept. The bike currently has 73 hours and 390 miles. It recently developed a "stumble", for lack of a better explanation, that occurs through out the rpm range but is more prominent around 3500 rpm and more noticeable in low. At 8-10 mph in low holding a constant rpm there is an audible exhaust stumble that can also be felt, almost like a misfire. Plugs look good, vent line from tank is clear, valves have been checked, problem occurs with gas cap on or off. In an unrelated discussion with my local dealer when buying valve cover gaskets, the tech told me about problems he has seen with a sensor on the intake plenum that relates to air fuel mix, and how it is sometimes confused with valve issues. I had never heard of this so I took it with a grain of salt. Has anyone heard of this? Any ideas on what is causing my issue? Thanks in advance.