rebuild factory muffler

[Jman]

Hi all, I have a strada rx200hp I purchased from Mike at Scootertronics.com and I have just finished rebuilding my factory muffler. I packed it with wire screen and bronze wool. I have not had a chance to test it yet but if it works I will post step by step pics.

[Jman]

Ok guys it works great I am just watching the aluminum case, but I think it will be fine. Here are the pics.

As you can see the great looking "Performance Pipe" is a bit small.
These parts are very cheap.
Bronze wool $4.00 per pack
Wire Screen $9.00
Rivets $3.00


Drill out rivets.

Remove old canister crap. Cut screen a little long for tight fit. Use the hole roll only cut the length.

Roll out screen and try to unroll the bronze wool so you can cover the screen, then roll the screen back up with wool in it.
Save one pack of fine bronze wool.

Wrap exterior of new screen cartridge with fine steel wool to prevent rattle.

Rivet ends back on.

See the diference.

Tested on a few short rides today, its a little loud but my wife said she could tell a difference in bottom end imediately.

So there it is. I guess next I'll put a K&N and jet on it. Has anyone just drilled out the factory jet? Oh by the way Mike at www.scootertronics.com is working on manufacturing larger dia. header pipe for some applications, so check him out he is a really cool guy.

[earlwb]

Cool, nice job.

[Jman]

Thanks, I read on the other thread you were experimenting with ideas on this subject. I hope this is helpful. I am extremely satisfied with the performance, especially when I think about the cost.

[baturalps]

good job, what about the sound? i dont like scooter exhaust sounds like a chopper, and sometimes it is hard to drive long distances

[Jman]

It is louder but not unbareable. My wife likes it and she is not into the loud stuff, she drives it as much as I do. Imagine the muff you have now is a bottle, when you do this it is like puting a larger bottle with a deeper tone and it is a liitle louder.

[Jman]

Ok after about 50 miles the packing has blown to one end and the screen has sagged in the middle. And yes it is louder now.
I believe that the issues are due to the fact that I am playing with the jet at the same time I think I have the jet to big, wich is causing too much heat.
Whatever the problem here is how to fix it.
Add a pipe With 1/2 inch holes It is more rigid and will handle the extra heat.
Here are the pics.
Too hot?



And the cure.


Place the pins through the mesh and the holes in pipe to keep pipe in place. Add more packing.

[ksuflash]

if the inside of the muffler looks like that after 50 miles, I am unsure if it will last more than a few hundred. If ya don't care about rebuilding it often then you should be good to go. I just spoke with a buddy about exhausts and the color change on them. He specifically said that a blue tint exhaust means way to hot.

-ksu

[wireburn]

Hmm, usually a too big jet will run cooler. Leaner=hotter, richer=cooler.

-Mike

[Jman]

Yes Leaner=hotter, Richer=cooler engine temp.
Too much fuel causes exhaust gas temp to climb, if you notice in the picture only the last 1/3 of the muffler changed color.

[swakk]

i did the same job in the past , but i used a steel tube where i make holes (a lot) and inox steel wood to avoid the consumption of it
and it worked well
forget your grid and don't put anything inside that could burn at high temp

[earlwb]

I do not remember steel wool being good for muffler packing. Unfortunately steel wool burns. You can light it up with a match most of the time. I would suggest the fibreglass muffler packing as a better choice it lasts a lot longer.
I think you are on the right track, it is just the packing that isn't working out well.
A long time ago, the last time I was broke and needed some packing, I found a old muffler that wasn't being used anymore (it fell off a car on the road), so i cut it open and pulled out the packing and reused it.

[swakk]

inox steel wool doesn't burn (yes , it's not like steel wool, but like a flat wire in inox)

i posted a pict of this some month ago for the same purpose

but i don't know if it's easilly available in usa....

[earlwb]

Cool, thanks for the info, I missed it above. The special INOX Steel Wool looks pretty good, www.amfi-usa.com/amfi-products.htm
Learn something new every day.

I think that JMAN had used simple bronze wool as shown above in his pics. The bronze probably burned out (melted) pretty quickly. I also think it probably needed to be packed in more tightly too. In order to help support the inner screen better. A steel tube with holes in it would be better, as the wire mesh screen would tend to get pretty hot and get soft from the heat.
Exhaust gases are amazingly hot, most people don't realize just how hot the gasses get either.

Hummm, That might make for a good test instrument to have on a bike, measure the exhaust temp, as it would make choosing a jet much more precise.

At WOT, values between 850ºC (1562ºF) and 900ºC (1652ºF) are often considered ideal; temperatures below 800ºC (1472ºF) are considered too rich; temperatures above 925ºC (1697ºF) and approaching 1000ºC (1832ºF) are considered dangerously lean and can result in excessive engine detonation (knock) and possibly burnt or melted components (valves, spark plugs, pistons, rings).

Bronze melts at about 1700 degrees F.

[swakk]

i never checked my combustion from this side... it's pleasant, i'll try thanks

[Jman]

Thanks I will look for INOX. The bronze is to soft. But if anyone wants to know the size of th factory main jet in the Strada RX200hp (155cc) it is a 115 not a 200 as it is stamped. So if you want your muf the same color as mine put a 220 jet in and watch the fire exit your tail pipe.

[demon]

haha 220 jet... omg you must have looked like one of those top fuel dragsters with the flames pouring out the exhaust...hehe

people using a 30mm carb are only using 130-138 jets i cant fathom how much fuel a 220 dumped and more so.. i am amazed that it even ran w/o fouling the plug

[lewtwo]

>> put a 220 jet in and watch the fire exit your tail pipe <<
Add a nozzle to the end and call it the after burner. ;D

[Jman]

Yeh I felt like an idiot when i found out 200 was a casting #, and not the size.
But it ran like a bat out of hell at wide open throtle, and any other time it just ran like hell.

[swakk]

different version from france...
because you don't speak french and i'm too lazzy to make a decent traduction, just the picts




























































thanks buck-roggers for this great job. :-D

[natefromogden]

swakk said:

different version from france...
because you don't speak french and i'm too lazzy to make a decent traduction, just the picts

Very decent job of fixing up that stocker muffler. If you can, all the replacement systems use a much better flowing header pipe than that skinny stock one. I thought I had a side by side photo of the difference but I can't find it tonight.

[Jman]

Very nice job swakk.
I just posted a new thread on the 150 forum, I changed to totally different design which flows great also, and is not as loud. Check it out sorry, got carried away and forgot to take pictures.
Thread is call (Factory Muff Mod 2).
Oh, Thanks, the scouring pads worked great.

[elusive502]

Hi all. If i gut the muffler I know it will be loud but will it hurt the engine? I mean jsut gut it and put it back together. If i do this will I need to rejet and if so which jet? I have a roketa mc 20 150cc thanks any help would be great.

[larrybcool]

wonder where they got the pipe for the muffler mod and what size is it .I look at alot of places anyone got a idea where to get the piping from ?