Exhaust Packing

[kdtrull]

My little XT came with an FMF Powercore 4 exhaust.  It is a nice throaty sound but is mind-numbingly loud.  I've got two different kinds of glass packing material but they both oscillate around in there so much that the material disintegrates in about 50 miles.  Any ideas how to make the packing hold up?  I'm tempted to buy another stock assembly but would rather figure out a way to make some packing work.  Please advise if you can.

Thanks,
kdt

[01YZF6]

Only time I ever repacked a can was a pita!
Had to drill the rivets out, remove the cone and core.
I used some packing off eBay, rewraped in one direction, laced tiewire around it, then added another 2 layers and tie wired that to keep it tight.

It worked well, and dampened the sound quite a bit.  Then I inherited a new exhaust and passed it on later.

[kdtrull]

I think I'm facing the same problem.  The cone comes out with one screw.  Then there is about a 1.5 in hollow perforated tube inside the core...which is where I've been shoving the packing in that subsequently self destructs.  To get the core out and properly wrap the outside of it will require a bunch of drilling and banging and it will probably look like crap when I'm done.

I sure wish I could find a way to construct a sturdy insert for the hollow part.  I watched a video of the official FMF quiet core insert last night.  I couldn't tell any difference at all with their quiet core insert.  It's just a stainless hollow tube that sticks about 1/4 the way up in the hollow core with no additional dampening material....useless.

[lazeebum]

LOUD PIPES SAVE LIVES!!!! ;D

Sorry man, I couldn't help myself.

[kdtrull]

LOUD PIPES SAVE LIVES!!!! ;D

Sorry man, I couldn't help myself.

Loud pipes make me hungry for Valium biscuits and scotch gravy.

[Chuck A.]

I used stove rope and wand it round the baffle. Tied each end in place with stainless steel wire. Same rope used for oven gasket material. Comes in different diameters.

[IceCold4x4]

I found when doing my zrx exhaust if you wrap it as tight as possible (to the point of having to almost hammer it in there) it stays alot longer...

[kdtrull]

I found when doing my zrx exhaust if you wrap it as tight as possible (to the point of having to almost hammer it in there) it stays alot longer...

Well...I just finished an experiment doing almost exactly what you said.  I used a screen from an automotive air filter to wrap the glass.
Interestingly, one of the largest filters on the shelf was one of the cheapest....must be for a Chevy or Ford truck.



Giant, hollow, obnoxious "muffler":


Scooter joint....now chill, loudmouth:






I think the phone is normalizing the volume...it is quite a bit quieter...although you can't tell that much in the video.

I'll pull it after tomorrow's ride and see how it survives.....hopeful but not optimistic.

Keep hope alive!
kdt

[IceCold4x4]

the packing goes around the outside of the hollow tube...

[kdtrull]

the packing goes around the outside of the hollow tube...

Yeah...this is meant to be a workaround.  I've already tried to pull it apart to get to the outside and almost destroyed it....the other end has about 40 pry marks all the way around the outer shell.

[IceCold4x4]

the packing goes around the outside of the hollow tube...

Yeah...this is meant to be a workaround.  I've already tried to pull it apart to get to the outside and almost destroyed it.

ah ok.... lol for a second there i was wondering.

[kdtrull]

I would much rather do it like you had in mind but I pulled all the screws (no rivets) but there is some kind of silicon goo between the core and the shell.  I pulled, beat, banged, and pried....it would not let loose and I was really making a lot of cosmetic damage.

Edit:  Actually, the outboard end IS rivets.  I was trying to disassemble from the inboard end.  Maybe I need to drill the rivets and go at it from the outboard end??? 

[Chuck A.]

Putting the packing in the center of the pipe can cause to much back pressure from blockage and burn a valve.

[kdtrull]

Putting the packing in the center of the pipe can cause to much back pressure from blockage and burn a valve.

Yep....I monitored flow for that.  I still have way more flow than the stock pipe.  Also....the last inch or so of the flow path is unobstructed because the spark arrestor sticks about 3 inches up into the pipe.  All the glass would have to blow out of the makeshift pack and jam up around the arrestor to really cut the flow.

[LawnmowerRG]

I don't imagine you will have much different results with what you have done. You should take the cap off the exit end. The inlet end should be sealed on. Hence the reason you can't get il off.

I have seen people use heavy grade steal wool to pack with also.think like a kitchen scrubber. I don't know where they got it, but it was from an industrial job site.