Do SE plug wires screw up the anti-knock ion sensors on these bikes? I know different spark plugs will, but what about the Screamin' Eagle plug wires? Why would Harley put out a wire that would mess up their own bikes? I've searched and read for days, and the general consensus is 50/50. Some say yes, some say no. I wanna put some on my new FXDL, but not if it screws something up.So, what's the REAL truth?

 

My SE plug wires wires didn't screw up a thing. Of those 50% that say they will how many have actually used them and have seen the spark tables to know?

 

SE plug wires are designed to run correctly on HD motorbikes.

 

No - in the very beginning of ION sense the wires did then they caught it. It is no longer an issue and hasn't been for years.

What will screw you up is some aftermarket plugs. Some work, some don't. This is because the spark plug is used as part of the ION sensing circuit. If you look at pre ION sense coils they had 3 wires. ION sense coils have 4 wires. The ECM steps up an 80V signal that is used for ION sensing.

Automobiles that use a similar ION sense circuit will also get messed up by some spark plugs. Many aftermarket wires are also a nightmare for the ION sense system.

People who want to have the lightening bolt spark plug wires that light up or any other thing that changes the resistance in the secondary circuit need to purchase an SEPST and disable ION sense.