BMW R1200RT/R1250RT Forum

I don't know what's going on. For no apparent reason, for the first 10-20 of running, my engine with start sputtering and then die whenever my RPMs get below about 2k. So during that time whenever I am stopped, or in neutral, I have to keep the throttle slightly applied, which is incredibly inconvenient. This is a new issue. So far I have replaced spark plugs, air filter, oil filter/oil. I looked inside my fuel pump controller and didn't have any moisture buildup, I tried bypassing the FPC and that didn't change anything. I opened my gas tank and check for obstruction/debris but found nothing. I have a carbon filter for emissions or something that when removed didn't seem to change anything. No idea where to go from here. I'm current ly looking for a GS-911 owner in my area (SoCal), but haven't had any luck. [size=2px]Any tips or suggestions on what to check/try next? Thanks![/size]

These two videos show methods of checking ignition stick coils, might be worth a try.

https://www.youtube.com/watch?v=hMJWr_BdNO8

https://www.youtube.com/watch?v=j_vm7C5buVU

Classic symptoms of a failing coil or coils! I carry spares on the bike with me as they're an easy roadside fix if you have basic tools with you. A quick check is to rev the engine up to around 5k rpm, then as it winds down listen for any 'popping' in the exhaust - it's usually the secondaries (lowers) that fail and give this symptom, together with the one you've described. If it's a main that's on its way out, the misfire would be very, very noticeable when riding!

Pete