Really odd noise from right exhaust-with video

[Valker]

This is coming from my right exhaust pipe about halfway back. Bike has to warm for about a minute before the noise starts. Bike is in neutral. I carefully replaced the right side exhaust gaskets and correctly torqued the nuts with no change in the noise. I did not make ANY changes to the bike before it started this noise.
I'm not sure how BigBF is with noises. Any suggestions?

https://www.youtube.com/watch?v=wn7gJc4QasM&feature=youtu.be

[Garland]

I have heard the noise resulting from loose exhaust manifold nuts on my bike, and it doesn't sound anything like that. I would guess a problem with valve clearances, but don't understand why it would happen all of a sudden. Do you have a mechanics stethoscope to try to isolate the origin?

[Jess from VA]

No expert here, but that sounds like something loose inside the pipe.

The tapa tapa tapa (rpm driven) seems in synch with the cylinder exhaust strokes..... blowing a loose something (growing louder with more air/push).

You always wanted a glasspac anyway, right?    

[Valker]

I have heard the noise resulting from loose exhaust manifold nuts on my bike, and it doesn't sound anything like that. I would guess a problem with valve clearances, but don't understand why it would happen all of a sudden. Do you have a mechanics stethoscope to try to isolate the origin?

Used the mechanics stethoscope to find the noise loudest at the start of the actual muffler part. No sound coming from the valve cover, header pipes, or engine itself. I removed the right exhaust and shook it all about, but the hokey pokey routine gave no rattle at all. New exhaust gaskets upon reinstall. I don't really mind the glass pack mod, but I DO mind spending big bucks to NOT fix the real issue. I'm bumfuzzled!

[Rio Wil]

You might try pulling each plug wire on that side off one at a time to see if you can determine what cylinder/pipe the noise is in.  As I remember, on stock exhausts, each cylinder has its own path through the muffler.......then might be able to use compressed air from the header end to replicate the noise.  It sounds like one of the baffles has broken loose inside the muffler. The muffler is made up of 3 sections, the front (header) 7 inches, the middle (3 divided chambers) and the rear 7 inches.  The front and rear are basically the same........pipes with several drilled holes to allow the gas to pass in one drilled pipe and out another drilled pipe to make its way down along the muffler.  The middle section is simply 3 equally divided chambers (like a pie cut in 3 pieces).  One of the pipes or pie baffles seems to come loose under heat......

[okweaver]

This sounds very similar to my stock exhaust when the lower of three forward baffles rusted loose from the bulkhead, inside the muffler.
I resolved the problem by sawing both mufflers in two just behind the forward bulkhead. I gutted the forward section and then welded the mufflers back together. No more rattle.  I love the resulting beautiful deep purr.
If I knew how, I was post a pic of the removed pieces.

[John Schmidt]

Weaver, send them to me and I'll resize and post your pictures....it's really easy. I'd be interested in what was done to the mufflers. I'm at:  stuffy402@aol.com

[Valker]

I'd love to see how you fixed this.

[okweaver]

Sorry, I only have one pic of the removed pieces.  It was quite the battle of twisting and pulling but we (my son and I) persevered. I never took time to take pics during the struggle.

So, for a verbal description.  We removed both exhaust pipes from the bike. Removed the chrome tips and chrome covers.

I had access to an industrial band saw and sliced each muffler 2" behind the forward baffle.  There are tell tale spot welds indicating where the baffle is located.  Apparently 15 years of condensation settling in the bottom of the muffle will take its toll.  The lower pie shaped baffle section had rusted enough to allow the freed baffle tube to slide forward and back.  Every exhaust stroke would cause it to bang against the muffler skin.

That left the forward empty muffler tube with three pipes showing on one side, and the other half still containing the three welded chamber separating walls and the drilled out aft baffles.

I had scratched witness marks across the cut line before we started so I could realign the halves before welding.  I used a MIG welder which worked well but required a lot of grinding to get the chrome cover to fit back on well.  Using a TIG welder, hand feeding the rod, would have probably had better results, aka less grinding, few blowouts.

But, I forgot to say why I cut them open.  I had figured out the problem before I started cutting.  My mufflers had already had the piggies cut and the baffle ends drilled before I bought it 50K miles ago.  I used a long 3/8" wood dowel to "reach" through the drilled rear baffle to the forward baffle.  To my surprise, I was able to move the forward around, side to side, fore and aft, and bang the sides.

The resulting exhaust tone is perfect for me.  It purrs loud enough to hear at any speed but will really growl when you roll the throttle.  My son has open Thunder headers on his 97 which sound great for the first 15 minutes but I will not be changing mine.

[John Schmidt]

OK, here's a picture of what OKWeaver removed from his mufflers. Doesn't look like he left much in there, judging by the guts in the pic. 

[Valker]

Thanks...looks like it may be glasspacks time.

[BigBF]

Thanks...looks like it may be glasspacks time.

I'm just guessing what I see you describe and video. It might be from the drain hole in front of bottom muffler??

[Valker]

Already had the glasspacks done.

[BigBF]

Already had the glasspacks done.

Oh well... I guess I'm too late.  It's hard to keep up in vrcc board. I have been so busy working on Valk. Right now I'm working on Valk in Texas. Yup I'm having fun in this heat lol!

[Joe Hummer]

Already had the glasspacks done.

Valker,

Did this solve your problems?  Sorry, I just saw this post or I would have weighed in earlier.  My guess is that it is where the 3-pipes enter the muffler can...which is behind the cover at the foot pegs.  I have had two different exhaust have the welds come loose (if they were even welded in the first place),  On the first one (my bike), I had the muffler shop weld the pipes to the plate when they were doing my glass pack mods.  On the second set of pipes (Monica's), we didn't discover until after the glass pack mod so I used the clay-like JB Weld.  I rolled out a small piece and pressed it up into place with a popsicle stick.  It seemed to work very nicely. 

Joe