Repacking Question

Just wanted to see if anyone here may have repacked a pipe using stainless screen instead of fiberglass packing?

I read about this maybe a year ago and seems some bike operators as well as off road truck people have been going this route.

I have always used the fiberglass packing but last year in an attempt to get more longevity out of a packing job I tried this ceramic fiber blanket insulation that is supposed to withstand up to 3200 degrees.It is somewhat similar to the fiberglass packing material. Some people have raved about this being the holy grail in muffler packing. I was not so impressed. It did last a year....about the same as fiberglass but I think it is more brittle and once it does start to go the big four stroke pulses just hammer it to pieces and spit it out the pipe in a hurry, as mine got way louder in just a couple rides....kind of similar to when fiberglass packing goes South.

Anyway I am now thinking about trying out the stainless steel screen method to see if it will last AND be fairly noise reducing, so figured I would see if any of you guys might have tried or even heard about this?

Stainless steel is great, untill you get it very wet and very hot, then it turns into steel wool, and disintegrates.


The large compressed fiber blankets last the longest.

I have been using those fiberglass blankets for years and depending on how much use a bike gets they seem to last me about a year then start to get louder. That is why I tried that ceramic stuff, but was not that impressed with it. 


 I have seen where the stainless steel, steel wool type works pretty good but as you mention goes away if wet or real hot. Not sure why it goes away when wet....probably has something to do with the fact that steam can go up to thousands of degrees although probably NOT in a muffler as it would tend to get expelled pretty quickly. I know from machining LOTS of different metals that real small thin fibers can actually light up and burn if conditions are right! That could explain where it goes when real hot. 


I once had a ball of Titanium chips go up in a lathe bed, but Ti is one of the flammable metals and it sort of glows white hot and moves rapidly down one chip. Every time it crosses or touches another the burn takes off in those new directions as well! Was a VERY exciting day at work that day!


 They say regular steel wool will burn real similar to that Ti fire I had because it is covered with an oil used during manufacturing  and the oil is what gets it going, then as it travels down each little piece it grows every time it crosses another.


 This ceramic crap you put a wrap of stainless steel screen around the core perforated muffler piece and then the ceramic blanket over that. Probably cause it does get broken so fast from the pulses and the stainless screen helps protect it from the pulses? Have to BE SURE to have it OUTSIDE the first time you fire it up too. I DID NOT, and it made huge mess of little fibers settling all over everything else in my shop. Du-OH!


 Anyway I am thinking about trying it with just stainless screen screen in there. Not sure how many wraps I can get around it, or how much weight it will add, but am hoping somebody else might have tried it.

A year of packing life is very good, so I'm not sure why you are so adiment to get more life out of it.


I get about 30 hours out of mine, which is 1/10 of my riding time per year.............

 I ride a lot and have LOTS of bikes to maintain. Really do not need/want the practice or more experience packing pipes.....would MUCH rather be riding!


 My old '99 WR has LOTS of miles on it and I bet it needs to be re-packed as well but it is a White Brothers pipe, (E -series carbon I seem to remember) the one with a carbon fiber can. Real similar to the old Super Trapp style ones with the stackable end caps that also serve as a noise suppressor and spark arrest. I have never even pulled it apart as it never got loud! Need to though.


 This one on my '03 is an FMF Ti series but last week it was noticeably louder at the end of the ride than at the start. It was WAY to loud for me when I first acquired it. Was on that bike when purchased. I built a new end cap with smaller outlet holes and now wish I had gone smaller still. The older I get the more I like quiet .....I can be more stealthy in the woods!


 I bought this kit for use in a  car/truck muffler when I re-packed this pipe last year using the ceramic fiber, but it did not come in till after I had it done as I got in a hurry to keep from missing a ride or two. I believe it might have enough of the stainless screen to do a scooter pipe, if not I guess I can always fill the extra space with glass or ceramic as I still have some left, but if I got word that somebody had already gone this route and was certain it would last longer I would buy some more to make sure I have enough screen to try it out and see.....may go ahead and still do that though. Makes sense to me that it would last. 

Stainless steel is great, untill you get it very wet and very hot, then it turns into steel wool, and disintegrates.


The large compressed fiber blankets last the longest.


Who's large compressed fiber blankets last the longest. I think the stock ones seem to last the longest. It almost looked like the used brass wool in some places on the stocker.

 I believe the stock bikes that do use fiberglass seem to last so long as they have machines doing the packing and assembling, They have it down to a science and can really get them packed good and full. THAT seems to be the ticket to getting the most time out of fiberglass. Once they start to burn out though and get a void in them,I believe the big four stroke pulses pretty much pulverize it faster as they get more and more room for the pulses to hit what ever is  left. These pulses help break it up ands spit it out.


 I know I have seen small chunks of fiberglass get spit out as the pipes get louder.


 I seem to get about the same length of time/use out of about all of them as long as you get them packed good and full.


 That is why I think the screen may be the hot setup as it will not cook out or break apart over time.

I've got a roll of pipe wrap for exhaust headers.  What about using that inside the muffler?

I've got a roll of pipe wrap for exhaust headers.  What about using that inside the muffler?


Hopefully you are joking.............

FMF Q4 on 2 bikes.  When new they sound great and not too loud but after only 20 hours, if that, noticeably louder.  Confirmed with an iphone decibel meter.  Pull the packing out, stir it up and repack, get it just right and good for another 20. Too tight or too loose and it's louder.  I got sick of it and made my own mechanical baffle that's not dependent on fiberglass to shut it up.  Tried several designs before I got one that worked well.  

I've got a roll of pipe wrap for exhaust headers.  What about using that inside the muffler?

 I do not think that would be such a good idea.


Fiberglass packing allows some of the sound to enter all the small voids in the glass after it passes through all the little holes in that perforated pipe that the fiberglass is wrapped around.


 I think that heat wrap is probably a little to tight a weave for it to work is also heavier than either the fiberglass or that ceramic stuff. Of course I have not tried the stainless screen wrap method yet and I bet it will be quite a bit heavier as well. And screen will also have bigger voids so not to sure how well it will actually work.


 I could be wrong though so you try it and let us know! HA!


 Stock pipes that use baffles are nice in that they are designed for the pulses and size of the motor. They usually have 6-10 turns and bends and silence the thumps using a combination of those turns as well as little chambers custom designed to take a lot of the bark out. Problem is they are usually steel and all that piping makes them real heavy. They do last a long time though. what did you do when you built your own. Series of discs? I have heard/seen where a series of discs with big diameter, little diameter, stacked up, just larger than and that fit over the perforated piece work well. Saw a similar drawing once using this same concept for a pistol silencer. But DO NOT go there or the man will throw you in the slammer!


 On the pipe on my '03 which is an FMF Ti (race series) it was so loud it would give you a headache. Had a hole oin the end about one inch in diameter so I built about three different  rear baffles with increasingly smaller holes and different patterns. Finally got one that knocked the edge off the sound. With good packing it is real nice....but still gets a tad loud as the packing goes away.


 I guess I am just lazy as I like to ride more and work on the scoot less!

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