Repacking mufflers

[wirespokes]

In 11K I've repacked the bubs twice and it may already be due again. It's hard to tell since it blows out so gradually. Last time I knew when a couple different friends commented how loud it was. Hadn't really noticed till the. Another indicator is it pops more on decel.

Last time I tried using a method off Utube packing house insulation tightly and cramming it in there. The time before I used Kiln insulation.

I've thought of building some sort of baffle to replace the original tube and end plate, but not sure how to design something like that.

Any recommendations on the best way to pack a muffler so it lasts a while? Six or eight months doesn't cut it. How long should I expect the packing to last?

Any recommendations on stainless exhaust systems? How well do the LaFranconis hold up to every day use? Is the chrome durable?

[Groover]

Maybe try this? Though, it might be similar to the Kiln wrap - compare the specs perhaps.

https://www.amazon.com/MPK1-Material-2-Stroke-Motorcycle-Universal/dp/B011PW22DE

[chuck peterson]

I had better success with the White Bros muffler packing material online or at a local shop...in a flat sheet roll it onto the Bub insert...but ...I used 1 1/2 sheets for each...then I found a heat resistant tape, 3/4 or 1" wide and crisscrossed the packing in diagonal lines(think of straps on a Roman sandal)...I used a countertop to compress the packing as tight as possible while rolling it on...don't use Fiberglas  insulation from Home Depot...

Yes, it did not last long, but it sounded perfect with a repack. Drill out the rivets and your there..I'm thinking of my long G5/T3/T/V1000 Bubs...I know there was a shorter louder can for loop and lemans models..also avoid water into the packing when if your cleaning, I think it made it worse

That ceramic packing suggested by Groover looks like a good idea..

[Sheepdog]

I tightly wrap the baffle with the fiber batt and secure it with one or two pieces of masking tape. Once in place, the tape will release as it heats up and the batt will fill the available space. This was good for about three years on my V&H 4-1 on my CB750F.

[Toecutter]

I used a sheet of muffler packing, and some cheap masking tape on my CB750 4-1, holding up well a couple years in.

[nsmith]

I've had good luck with stainless steel mesh bought at an iron supply yard. Looks kinda like thin chain male. Just get it in there whatever way works. It will outlast any normal packing I can think of and it is cheap (guzzi content) I used this in a couple bikes with worn out mufflers and it really helps quiet things down to a more reasonable volume.
Good luck.

[Diploman]

Owners of KTM singles have had good results from packing aftermarket mufflers with a combination of S31 and Core Wrap stainless from Bristol Core.  Much better durability than anything else that has been tried.


http://www.bristolcore.com

[Ncdan]

Go to your local hardware store  and get sheets of fiberglass, same kind as used to repair anything made from fiberglass. Cut to the length of the bulb. Wrap the pipe and secure with wire. They will last several thousand miles.

[wirespokes]

I followed this guy's instructions last time, and I think they're good instructions, but have a feeling the LeMans 1000 has a way of blowing the fiberglass out of there no matter how well it's packed. Of course, I don't have any solid data having not opened it up yet, nor do I have a sound meter to indicate it's gotten much louder. Maybe I'm just getting anxious and it's fine...

https://www.youtube.com/watch?v=cWUsLVASfjs

Having already done it twice in the last year (the first time when I got the bike because there was absolutely NO packing in there), probably had never been repacked, and then again several months back. This last time I followed the above instructions and used some house insulation i'd had on the shelf. Maybe I could try the kiln insulation again, but this time wrap it tighter like the above video.

But I really like the idea of stainless wool or the stainless chain mail nsmith mentioned. Something a bit more permanent. I'll have to do a search on it. Nsmith - did the stainless mesh quite the exhaust note very much? I know it's difficult to quantify without a meter, but what do you think? I'd think it wouldn't quiet as well as tightly packed fiberglass.

[Darren Williams]

I have used stainless steel wool. Not as quiet as some stuff but lasts a long time. Wrap it and pack it tight.

I really don't like loud bikes.

[nsmith]

Wirespokes, Yes the stainless steel toned it down very nicely I have to say. I had some left over from a project
I had relining a bake off oven, If it can handle that environment for years of use it will for sure last a long time
in a muffler. I had two bikes a CL350 and a V50 both with gutted out mufflers and it worked excellent in both.
When you cut the stuff with tin snips remember not to expect the snip to ever be the same again.

[Groover]

I bought a sound meter at radio shack about 10 or so years go, works well and was cheap (under 50). Searched the web to see if I could find it to link it here, and turns out that there are sound meter apps out there now.. go figure, I didn't know until just now. If you have a smart phone, you might be able to find one for free maybe.

I've used steel wool in the past on 2-stroke bikes. If does last longer than standard fiberglass, but you might send sparks out your pipe when it starts to burn off as it gets red hot, and may also stain your chrome pipes of high temp.

[wirespokes]

Getting a sound meter app would require something that takes apps - I'm still using a flip phone. I might have to step up to a first generation I phone. LOL Hey, I'm cheap, except when it comes to motorcycles and gear. That's where my money goes - oh, and tools. The only thing that's interested me about having a new hand-held device is GPS. Getting lost can be fun and exciting so don't worry too much about that. With a good bike and plenty of gas, it's a fun adventure. Some of those earlier I phones are fairly cheap now, so it might be the time to upgrade.

Is there a good place to get SS wool or the chain-mail sheet? What grade of stainless wool works best? I'd expect coarse to hold up best, but might not quiet best.

[wirespokes]

Did some looking around and found a place called STEEL WOOL DIRECT. They've got steel wool for repacking mufflers - 4" x 1/2" x 30 ft for $23 shipped. Sounded like a good solution so called them up and talked to Tina. She said there's something better than stainless steel wool - ceramic wool. It handles higher temps than SS. They sell muffler packing kits containing a sheet metal baffle that gets wrapped around the core tube. Then the SS wool, then the ceramic.

While reading up on this stuff I ran across the data that fiberglass packing can last longer than 60K on a four cylinder touring bike. But a dirt bike or single, or a high performance two cylinder can blow it out in 7-10K. If doing track days, it can be as little as 2K.

Sounds like my situation exactly.

So now my question is whether to wrap them with the SS wool for $23, or go with what Tina says is the best - their custom packing kit for $39 x 2 = $78?

[Hymes Inc.]

Ceramic wool sounds a lot like rock wool wall insulation. Watched a supplier set up a propane torch directly on it at a home show and it never burned. He let it run until the can went empty.  Never thought to try that stuff. I think I will give it a try my next go round.

[wirespokes]

I'd never heard of rock wool insulation so looked it up. If you've got some, please let us know how it works, but I'd think it shouldn't be used solely by itself, but in conjunction with something like stainless wool. I think the recommendation was the ceramic wool went against the outer edge of the wrap. But it's permeable and gas can flow through it. Evidently there's a bit of science to this and the game is balancing permeability against the ability to withstand heat and pressure. It sounds like the rock wool wouldn't flow very well, but that's only guessing from the little data I've got on it. If you have access to some for the experiment, I'd love to hear how it works out. As it is, it looks like ceramic wool can be sourced rather cheaply on ebay so will possibly go that route.