I replaced all of the spark plugs with iridium spark plugs. The far left spark plug had quite a bit of rust on the outside of the plug, meaning water is sitting in the spark plug hole. However, I do not think that was causing the rough running at low RPM. While the newer iridium plugs did seem to ease the rough running a little, when I took it on a highway ride, it still ran rough. I also had a massive hesitation issue at about 4000-5000 RPM’s in 3rd gear and up. I pulled over, and unplugged the aftermarket gear position sensor. The bike ran smooth after that. I rode the bike to work this morning, and it had no hesitation or idle issues. I am wondering if the aftermarket gear position sensor indicator is somehow sending a signal to the fuel pump or ignition system to shut something off, because the hesitation felt like something was being turned off. If that’s the case, then likely there’s an issue with the wiring harness. I ordered a new OEM position sensor, and will plug it in to see if that fixes the issue. If not, then I have a serious problem with the wiring harness.
- Installed new iridium spark plugs.
- Applied thread locker to all removed bolts.
- Unplugged aftermarket gear position sensor indicator.