Anyone else got this Rattling noise - know what the issue is?

[LongBeard]

I've noticed a noise at 4500rpm to 5000rpm that almost sounds like a rattling noise. The noise is kinda hard to explain and is louder in 1st gear and gets quieter the higher in gear the bike is. 2nd gear is quieter 3rd gear is even quieter, 4th gear you can barely hear it, 5th gear is the quietest. The Spyder is a 2008 GS SM5 (manual). It has done this ever since I've owned it. The noise isn't there below 4500rpm and above 5000rpm. The bike still vibrates normally throughout all rpm speeds, so I am at a loss as to what this is. The noise sounds like it is coming from the engine area, but I cannot see any loose bolts or parts anywhere. I have spoken to my friends who know engines and they said it could be a number of things, being that it is a v-twin. Could be normal or could be a transmission issue as I do have an issue getting the bike to shift into a gear sometimes but not always. Sometimes it likes to hang in the gear I'm trying to shift out of on first attempt shifting. Second attempt always gets it to shift to another gear. Has anyone encountered this noise and figured out what the issue may be, (user error or an actual problem) if there is one, or does anyone have any idea what could be causing this noise or shifting issue? Thanks

[JKMSPYDER]

If this has been going on since you bought it, it is probably normal.

[Isopedella]

umm. when did you buy it?

[Bfromla]

umm. when did you buy it?

& what mods have you done to it?? Serviced by dealer or Diy? Yes very well maybe normal for your machine & maybe only a skilled ear can identify& locate personal experience with vehicles rattling is exhaust something , comes & goes as heats up course making difficult to find while hot.

[LongBeard]

I've installed a aftermarket slip on exhaust, had the ecm flashed, new tire, new spark plugs, changed the oil, flushed the clutch fluid twice, installed a K&N high flow air filter, and new brake pads. All of which I've done myself except for the brake pads and new tire. The noise has been there before all of the maintenance. I got the bike with just over 5k miles on it and it now has 12.5k miles on it.