Strange exhaust tones....
So, to set up a little premise.
I was riding down to Deal's Gap last weekend and my 'negative' terminal lead sheared off causing my bike to lose all power after a violent bang. Long story short the we fixed and crimped a new terminal lead on the wire and I rode the rest of the day with no problems that day. We/I was riding hard, 100+mph for a while, at least for more extended periods of time than what I'd done before and on the dragon/cherahola was pushing the bike hard.
So, on the way home on Sunday, I started to notice a bit of a 'vibrato noise' coming from my exhaust. A pulsating tone instead of the steady exhaust drone of a bike cruising down the interstate. Bwaaaaaaaaaaaaaaaaaaaa vs Bwaaaawaaawaaaawaaawaaawaaawaaa. If that makes any sense.
Well, Tues and Wed this week, the sound was more noticeable and has me wondering what might be going on.
Here is the diagnosis:
- There is nearly no sign of it at all in 1st gear.
- In 2nd - 6th gear, showing up at ~4K RPM through 7K RPM, the vibrato noise is quite prevalent.
- Power delivery seems to be just as smooth as it ever was. Acceleration is smooth as well. There is no backfiring, pinging, surging, choking, sputtering, kicking, fucking, rocking, knocking, rattling, chattering, from the engine.
- Every bit of the annoyance seems to be coming from behind me.
- There seems not to be any power loss to the bike (if there is, it's awfully minute)
- The sound of the exhaust is it's normal pitch, but with the vibrato added in at the aforementioned RPMs.
- Checked all basics: oil, tire pressure, batt leads, cracks/broken stuff on bike, leaks, etc...
- Removed air filter, inspected filter/air box, replaced filter.
- Re-mapped my PCIII fuel injection computer.
- Removed slip-on exhaust cans/inspected, nothing.
I've googled the problem, searched my maint manual, talked to a professional auto-mechanic of 15 yrs, all with no promise of what the hell is going on. So, I'm at a loss with what is going on with my bike.
All in all, it doesn't feel like there is anything wrong with the bike. But the exhaust tone sounds like a fucking annoying opera singer. It's annoying and prevalent enough to make me think there is something wrong with the bike, especially since I've never ever noticed it before in the 3+ years of owning it.
I don't want to take it to a dealer and try to see what's wrong with it, but between myself, other riders, and mechanics, no one seems to know what might be wrong. Anyone herehave a clue? I just find it strange that it came about after my neg terminal lead broke off and the bike shut down a bit violently. But after fixing it, seemingly I didn't notice anything wrong the whole rest of that day riding, and not until the next day.
Slow is smooth, smooth is fast.