catalytic converter mufflers

BarelyAWake said:

lol yea - defo, forgive me, I had gone and typed alla that bfore I saw you had ordered it already

I like the silencer style and by cutting the headpipe it comes with & adding yer own I think it'll work well - the 12" thing is optimum, but does little good if the pipe wont fit w/it so w/e works I figure.

The hours of "entrainment" whilst tinkerin' outa be worth the twenty bucks anyway as ya said

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Nothing to forgive. Honest answers are the best ones for sure. It will be interesting at least and maybe I can come close to the 12" optimum.
What are you going to do for the kickstand? Will that exhaust get in the way of a center stand or are you going to fab a rear drop stand? I was thinking about the rear drop stand for bikes which didn't come with them and thus don't have the little flared out tab to act as a stop. Why couldn't you drill a small hole there for a bolt and let the bolt act as a stop? In looking at the Elgin and the American I realized that my center stand on the American might be a problem.
SB

Regarding the rear kickstand and vintage drop stand. I had one of those rear spring loaded stands and never found anything it would work well on. I still have it sitting there waiting for the right bike. One problem for me is that the axle is where the hardware for the kiddie trailer fits and the two conflict. Dog wins, stand loses.
I found that the copper pipe drop stand I made for the 39 Elgin has worked well so far. As you know, I made several versions of this and what I have learned is: In the future when I make them they will stay copper with no attempt to paint them to match the frame color. If you actually ride the bike and it isn't a show piece it is going to get scuffed up and the paint will suffer. Better to let the copper "antique" itself with exposure to weather and develop it's own patina. I covered the bottom (horizontal run) which is in contact with the ground when in stand mode and contacts the rear fender/fender catch when in the 'up' mode... with elk hide. A little contact cement and then stitching to finish it up. Sure it is going to get scuffed some, but it is pretty durable stuff and what I use for moccasins. Let the leather take the beating. It makes the stand quiet where it contacts the fender. I've had no rattling around and so far have just used a leather thong fed through the two little bolt holes which held the original catch in place (long gone). I've said it is temporary until I either fabricate a catch or make a leather covered velcro loop to affix the drop stand in place. But I haven't changed it yet, I see, and don't find it much of a hassle to give a quick little tie to hold the drop stand up against the bottom of the fender. I'm not recommending it as a final solution, but it wouldn't be the end of the world either. When I redo the fender this summer repairing the damage I've done to it in a drive chain mishap I'll make it right. By then I'll see what you do and will know how. Ha!
SB
Good thread, by the way.

BarelyAWake said:

FYI - ifn' yer interested in silverbear's epic work, ya outa check this: http://motorbicycling.com/f38/rustoration-build-off-13144-27.html#post157940

Therein is found all sorts of fabricated goodies, from juice can tanks to leatherwork, from soldering to metal restoration - ol' silver is modest but very skilled

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Thanks for the kind words. I don't about that skilled part, but I'm learning and this is a good place to go to motorbicycle school. I doubt if I'll ever graduate, like the 18 year old guy I knew back in Jr. High named Charley Balls. Gave me my first and last chaw of tobacco in the boys room. I'll probably still be wandering around the halls here when I'm too decrepit to ride me bike. Ha! My ebay expansion chamber should arrive in a few days... can't wait!
SB

Whats the deal with the finish on the cat. pipes???If it`s powder coat, it don`t hold up to exh. heat at all.....Mine is bubbling now....But I took a long ass drill bit and drilled the dog snot out of it as deep as it would go....Sounds/works pretty good now.....But boy that pipe was quiet in stock form....

silverbear said:

I may just try that with the pocket bike exhaust... thanks for the tip.
SB

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if you do, PLEASE post pics, this is on my to do list as well

stuartracing said:

Whats the deal with the finish on the cat. pipes???If it`s powder coat, it don`t hold up to exh. heat at all.....Mine is bubbling now....But I took a long ass drill bit and drilled the dog soot out of it as deep as it would go....Sounds/works pretty good now.....But boy that pipe was quiet in stock form....

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LMFAO you aint kiddin. i removed the lower baffle out of mine. went from Meh sound to raped ape sound. lol. love it though

Yep your right....

stuartracing said:

Yep your right....

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TBH affected top end, very little. BUT helped low end get up and go quite a bit. sounds liek my chainsaw now. i fired it the other night. let it run, then shut her down, cops came by later on. wondering if i was running a chainsaw. i was like, " no sir, there over there, as cold as my ex gf, youre welcome to check. hehhad they checked the biek however.

how tough is installing an SBP ex chamber? i had no trouble with the kit and am pretty mechanically inclined, but i'm no mechanic and 70 bucks is a lot to spend on something i will never get installed properly.

I just ordered a Pipelyne Exp. chamber exh....I had one a few years ago on another build and really liked it....Fit and finish was great and the pipe didn`t mess up the performance of the motor to the point where it was a pita to get it back to where it was.....Tucks up out of the way, can still use the side stand, and not too loud, depending on the muffler you choose....
Dammit man, cops came buy....Yikes.....On my other exh., the muffler came un welded and I had to ride it back with open pipe for about 1/2 mile and it was LOUD too.,lol.....

Cabinfever1977 said:

These black mufflers use pallidum instead of platnum and is much cheaper but does about the same thing. I drilled the small inside holes toward the cap larger,works better but also a little more noise.

Also heres a pick i found of one cut in half.

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all catallitic converters have pallidium in them but it's normally paired with rodium and platinum.. pallidium is an oxidizer, and platinum actually reduces emissions.

essentially, only NOx gasses are left when using pallidium. but if it was all platinum, then it wouldn't oxidize carbon monoxide or hydrocarbons and just take care of the NOx gasses

Both Platinum and Palladium have very high melting points and both are effective catalysts in chemical reactions.Palladium can tolerate more heat than Platinum and that has some added importance to the auto industry.Both are used in catalytic converters to reduce auto emissions to meet increasing clean air standards.As both metals can be used in catalytic converters more or less as effectively as each other, auto manufacturers will use whichever metal is cheapest.
http://www.preciousmetalinvestment.com/pgms/what-is-palladium/

Since our mufflers are around $20,the cheaper of the 2(platinum or Palladium) will be used and probally will be mixed with other cheaper metals like rodium or gold. Right now Palladium is alot cheaper than Platinum.

another thing about the cat mufflers, they make the bike sound like a 4 stroke at idle.. and they rob power like crazy over the standard old style with the long tube attached to the endcap.

i personally wont be using these.... inferior things.

Cabinfever1977 said:

Both Platinum and Palladium have very high melting points and both are effective catalysts in chemical reactions.Palladium can tolerate more heat than Platinum and that has some added importance to the auto industry.Both are used in catalytic converters to reduce auto emissions to meet increasing clean air standards.As both metals can be used in catalytic converters more or less as effectively as each other, auto manufacturers will use whichever metal is cheapest.
http://www.preciousmetalinvestment.com/pgms/what-is-palladium/

Since our mufflers are around $20,the cheaper of the 2(platinum or Palladium) will be used and probally will be mixed with other cheaper metals like rodium or gold. Right now Palladium is alot cheaper than Platinum.

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great use of google, but that is sorta right and sorta not right... a good 3 way catalitic converter ( found in most 1995+ vehicles. and all within the last 10 years ) will have palidium, platinum and rhoduim.. I'd have to go thru some books of mine to find out which 1 does which, but IIRC, pallidium oxides carbon monoxide into carbon dioxide, rhodium oxidizes hydrocarbons, and platinum reduces Nox gasses into nitrogen and oxygen.... the way a catalitic converter works is thru the prosess of oxidation ( adding oxygen ) and reduction ( reducing oxygen ).. product of this is also heat.. if you have an infared temp gun and it's colder above the cat in the muffler, than it's working, but if it's colder below than it's not doing a thing.. I chucked mine before I thought about checking it

these bike cats most likely have just rhodium or just pallidium. which is only going to reduce carbon monoxide or hydrocarbons, my guess would be rhodium for the unburnt fuel ( hydrocarbons ).. it's the cheapest and these are 2 strokes so they spit out quite a bit of unburnt fuel

BarelyAWake said:

The solution lol;

"I needed the headpipe for a different project" and that's the result

It's a modified SBP expansion chamber, ported stock pipe & extended glasspack silencer. While the spring retention system on the SBP manifold is great and reduces metal fatigue - I couldn't bear to have the blue hi-temp silicone on my vintage ride... it just kinda clashed and Ima slave to fashion I guess. The extended glasspack quiets the exhaust to roughly equivalent to stock (sounds different/better - but no louder) and other than being 6" or so longer has little/no effect on backpressure as it's a clear passage straight through.

It's a pretty easy mod (glasspack) as it's simply 2" aluminum conduit, a chunk of metal window screen, a lil fiberglass insulation stolen from my wall & a coupla pop rivets, the stock head pipe slid right in to the expansion chamber with a lil chunk of the SBP system as an adapter (yus, I still need to trim & paint the one lil exhaust clamp) o.o

I liked how the curvature of the stock pipe pretty much matched the bike heh *shrug*

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I have a question for you. My poor boy expansion exhaust came yesterday and I'm doing some figuring on how best to mount it. It came with a little exhaust manifold which fits the engine so I don't really have to cut up the old muffler or pipe. What I'm thinking to do is use a section of the new pipe which needs to be cut off anyway as a coupling with 7/8" handlebar as the section between the manifold and the expansion pipe. It fits perfectly inside the expansion pipe and is the same diameter as the stock exhaust. I see that you have a U bolt joining sections together and am wondering if that alone is enough to seal up the union or if you needed to use something more to seal it like some sort of muffler sealant/goop/stuff. If so, what is the magic stuff? I'm figuring that the handlebar will blend in pretty well with the chrome muffler and it is something I can heat and bend to shape... and (you know me) it is free and at hand. Is there a better way to do this? I suspect that the exhaust manifold is aluminum or pot metal, can it take being compressed under a union or would I be better off cutting the stock one from the old muffler and using that? As always, your opinion is much appreciated.
SB

BarelyAWake said:

For my application the U bolt clamp proved "good nuff" with no discernible leakage, but those pipes were a tight fit to begin with, I almost needed to cut a coupla slots to help expansion/contraction... but not quite. There is that weird sealant goo inna tube they sell for automotive muffler "patch kits" (usually comes w/fiberglass bandages of sorts) and I suspect it may work, there's not a whole lot of pressure in such a high-flow exhaust like this... but I dunno, I didn't need to try it. If the gap is a lil too large, you could always wrap the female pipe with a lil aluminum or tin as a shim.

I'd bet your aluminum can take being compressed w/a clamp - circles are strong like that... but the headpipe/manifold is made out of aluminum??? That's... odd... I don't think there's anythin' really to be concerned with, I doubt our lil engines could possibly generate enough heat even there (w/o a catalytic restriction ofc) to damage it... my "ol' school" brain is jus' havin' a hard time w/it is all lol

I'd give it a shot anyway, you'll always have the stock kit pipe to replace it should it be unsatisfactory for some reason I figure

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Thanks for your input. Maybe that little manifold piece isn't aluminum. I don't know what it is, but I'm going to give it a shot. The handlebar is really snug in both it and the expansion pipe. I may also use a little of the magic muffler goop as a sealant..what's to lose? The u bolt, is that like a muffler clamp or just a u bolt with a flat metal backing piece? I'll take a couple photos as I go and if this works out I'm going to buy another while the price is in the basement. The expansion pipe looks like a great mod especially for vintage bikes with a drop stand since that problem is already solved. Another great advantage of the vintage frame is the horizontal dropout slots so that no chain tensioner is needed for the engine drive chain. Love these old bikes.
SB