Surging & poor performance -- Need Help

[toolinalong]

Bob, Bob here....

again, how many miles do you have on the bike?

The other end is at the ignition coil which is underneath the large steel spine that the front shock attaches to; you have to take the tank off to get to them, I did it last weekend when I was trying to troubleshoot a problem similar to yours, but considerably worse. At that point you can check the coils primary (~.7 ohms) and secondary (~7200 ohm) resistances as well, though the word I have heard is that the coil rarely fails, which makes sense seeing how it is just an electrical transformer. When I measured my plug wires I got 5500 and 5800 ohms.

One mechanic has mentioned to me that the plug wires do need replacing occasionally.....and Beemer Boneyard sells what looks to be a nice 1/2 price replacement set.....

[R1150Rclean]

Surging makes me think partially clogged fuel injectors but an air leak in the vaccume hoses is a good possibility too. At idle my bike was missing every 6-8th ignition, loaded the gas up with some concentrated fuel injector cleaner and after just 40 mile the missed ignition at idle was gone, will see if it stays away.