Rush Mufflers - Exhaust Leak ? : V-Twin Forum: Harley Davidson Forums

Dogwood · 10-14-2007, 12:21 PM

I have an '06 FLHRI with 98" and GMR heads, these are exiting through a set of D & D Dualies (true duals) to a pair of Rush Mufflers with 1.75" baffles.

I have a strange sound that I suspected as an exhaust leak.
It sounds like a high pitched, fast paced chirp when the engine is above ~2200RPM and is more noticeable under acceleration.
On the highway, I don't hear/notice it unless I turn my head 90 degrees, so that 1 ear is pointing back, and it's very noticeable then.

To me, it's coming right out of the back of the muffler(s).

I called Rush (EPI) and their head tech said it sounded like an exhaust leak to him.
He said that Rush uses a thicker gauge steel and the muffler clamps should be overtightened by 5 to 10 ft.lbs. from the spec 60 ft.lbs., and that I should not reuse the HD Torca clamps, for they are one time use only.

I got 2 new clamps and tightened them to 70 ft.lbs., I still had the sound, so I tightened them some more, still no luck.

I pulled the baffles out, since they were fairly new then, the wrap looks like it was covering the area of small openings (there was only a few layers though) and the tape was holding.
Not sure what this should look like though.

Do you guys think I’m hunting this sound in the right area, or is it possible that a engine problem/sound could only show itself out the back of the muffler?

Any help or ideas would be much appreciated.

trucky911 · 10-14-2007, 01:57 PM

My Rush mufflers w/ 1 3/4" baffles make the same sound. I have the fullsack true dual conversion on my bike. I never heard the sound untill I put the true duals on. I had Reinhart true duals on my 2002 FLHTCI and it made the same sound. Reinhart said it was the baffles being a little loose and to take them out and make the inside end a little oval to tighten it up and reinstall them. I ended up selling the bike and never tried that. Last week I tried bigger baffles (2 1/4") and didnt like the sound and less performance. I screwed up the packing so I went to the local Honda Stealer and bought some new packing and reinstalled the old baffles. Did a run with my hog chapter today and didnt hear the sound. Maybe I fixed it....lol. I really wasnt thinking about it and my buddies bikes might have drowned it out.

Trucky911

Dogwood · 10-14-2007, 02:07 PM

Quote:

Originally Posted by trucky911

I screwed up the packing so I went to the local Honda Stealer and bought some new packing and reinstalled the old baffles. Did a run with my hog chapter today and didnt hear the sound.

Trucky911

Thanks Trucky911, when looking at the packing that Rush put in and it seemed "light", not enough to me, but then again, I have no real idea how much should or could be there.

How much do think you got in there now?

Can I wrap to much?

ceraaa42 · 10-14-2007, 03:59 PM

Just a thought, is the clamp at the end of the pipe? If not, it will not clamp down properly since it is over to much of the pipe that does not have a slit in it.

Dogwood · 10-14-2007, 05:48 PM

I had originally purchased the mufflers with 2" baffles, but got a pair of 1.75" because I felt the 2s were too loud.

So I found them, and used the fiberglas wrap from those 2" to add to what was there on 1.75".

A test ride found I still had the sound, once everything got fully heated up, but it was different in tone and volume, and after several more miles, I swear the sound was gone.

I'll put more miles on her tomorrow and see if this trend continues.

trucky911 · 10-14-2007, 06:06 PM

The packing I bought at the honda place came in a blanket 15"x20"x1/2" and was $9.95. I cut it in half and did 2 baffels. I cant remember the name of it. I also ordered another product from Cobra USA. Its 15"x10"x1". Had to get two packeges. It was $7.99 a package. Gonna keep them as a spare. Their web cite is cobrausa.com. But I couldn't find any thing on muffler packing there. The parts guy at the honda dealer found it in a J&P catolog I think.

Trucky911

Dogwood · 10-16-2007, 09:03 AM

Just talked to Gary at Rush/EPI, and he said that the packing should, after the tape on the front of the baffle burns off, move back to the rear of the baffle and stay there.
This is exactly what occurred with mine.
Adding packing, stuffing it with enough so that no, or little movement of packing to the rear happens, will change the sound and performance of the muffler.
He could not say how the sound would go, but the performance should suffer somewhat.

He also said that no one has ever called them with this complaint, and he believes the issue is elsewhere.
He's might be right, but where?

goingsking · 10-31-2007, 09:52 AM

I had the 1.75" rush's with no problems but changed them to the 1.5" baffles and developed that noise. I was thinking that the packing was a little on the light side and was considering adding some of the packing. I did have a problem getting the baffle into the pipe and had to compress the motor end of the tube a little to get it into the pipe. Perhaps that is where I am getting the problem. I think I am going to do what trucky911 did, add some more packing and also make sure that the business end is absolutly round and see what it produces.

trucky911 · 10-31-2007, 07:08 PM

Quote:

Originally Posted by goingsking

I had the 1.75" rush's with no problems but changed them to the 1.5" baffles and developed that noise. I was thinking that the packing was a little on the light side and was considering adding some of the packing. I did have a problem getting the baffle into the pipe and had to compress the motor end of the tube a little to get it into the pipe. Perhaps that is where I am getting the problem. I think I am going to do what trucky911 did, add some more packing and also make sure that the business end is absolutly round and see what it produces.

When i took out my baffles I didn't find what Gary told Dogwood. After 10,000 miles on them the packing was still all the way on them. Not bunched down. The right packing was black and very used. The left packing still looked new. I only had 500 miles on the bike w/ the full sack tru duels when I took out the baffles. Any way I have new packing in both mufflers now and i am still hearing the noise. It really dosen't bother me and I only hear it when I ride alone. Like I said befor I heard the same noise on 2002 EG when I installed the rinehart tru duals. Bike runs good and I got 41 MPG on the tank I drained on Tuesday....lol (drained by putting 108 miles on it on Tuesday and 154miles today)

Trucky911

Dogwood · 11-02-2007, 08:37 PM

Thanks for the input guys!

I did get some fiberglas packing and re-did the 1.75 baffles, I put enough that it would cover the inner stepped portion of the baffle and would allow for little to no movement down toward the end.
The sound was gone at first, but after about 300 miles, the noise has returned.

I wonder what these would sound like with NO packing in them?

I also have a set of D&D 2.5" mufflers that I tried once, I didn't like the look of the small diameter and they were very loud.
Perhaps I'll put those back on and see if the sound is still there, that is, if I can hear over these mufflers.

route66paul · 11-02-2007, 09:37 PM

Send your stock muffs to Fulsac to get them recored. The sound great and work better. They are the best thing for a true dual system.

trmn8r-II · 11-02-2007, 10:20 PM

I've had both, I'm MUCH happier with both the sound and porformance of my Rush 1.75 mufflers. Currently running Rush 1.75" with Fulsac true dual kit. Never noticed what you guys are having. I have the Rush's with removable tips. I do seem notice at an idle if I am behind the bike I can almost hear the billet aluminum tip "tinging" with each exhaust pulse, dont notice it on bike though.