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ass
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Discussion Starter #1
I bought a radiant cycles exhaust (http://www.radiantcycles.com/) cause it was cheap - list $60 shipped, and i love the way it looks, but its basically a header ornament. If its any quieter than running without a can, i can't tell. to be clear - it is unusably loud for my daily ride. Like ear splitting @ 75-80 mph.

I want something in that size range but quieter. pipe dream?

not really into those big diameter shorty cans.

I happen to have some perforated stainless sheet laying around... was thinking of rolling it up into a baffle. maybe add some packing. bad idea? good idea? would it help? it'd be like ~6 inches of baffle at the most.

was also considering a coffman exhaust, but i don't wanna spend the $$ only to find its just as bloody loud.

other options im not aware of?
 

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point it at the floor?

Put a large washer, between the header and the exhaust can ( not much of a can really like its tiny!)
Drill holes in washer out a bit at a time and test ( tedious but will 100% cut the noise)
Problem will be when you are happy the noise, you will have more backpressure and may not be happy with how freely the engine revs
 

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The Hell You Say!!
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If its riveted together you might be able to drill them out and see if the baffle is wrapped in fiberglass. If it isn't you can wrap it and it will reduce the noise, if it is then wrap it tighter so you can add some more then either use sheet metal screws or rivet it back together.
 

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ass
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Discussion Starter #5
point it at the floor?

Put a large washer, between the header and the exhaust can ( not much of a can really like its tiny!)
Drill holes in washer out a bit at a time and test ( tedious but will 100% cut the noise)
Problem will be when you are happy the noise, you will have more backpressure and may not be happy with how freely the engine revs
Having trouble picturing this. Is there something i could google?
 

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ass
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Discussion Starter #6
If its riveted together you might be able to drill them out and see if the baffle is wrapped in fiberglass. If it isn't you can wrap it and it will reduce the noise, if it is then wrap it tighter so you can add some more then either use sheet metal screws or rivet it back together.
I don't see any rivets. Im guessing that it's tacked together
 

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ass
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Discussion Starter #7
I've made a couple mufflers before. As far as packing material goes: stainless steel wool didn't do much quietening, standard fiberglass muffler packing material was ok,but using header wrap really cuts the dBs down.
Hmmm. Good to know. Re:header wrap, are you talking about wrapping the pipes in general or using the wrap to pack the baffle?
 

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Is my bike ok?
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Hmmm. Good to know. Re:header wrap, are you talking about wrapping the pipes in general or using the wrap to pack the baffle?
Using the wrap to pack the interior of the baffle. I did this on my '76 CB750 F and it was good as new, although sooty, 10k miles later. The stuff holds up better inside than it does on the outside. :D
 

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Among the Harley crowd there's the "lollipop" trick you can do to open exhausts, since on most bikes a purely open header causes substantial loss of low end torque and on carbureted bikes, often flat spots in the rev range.

Just get an eye bolt that's about 1/2" the width of the inside of the exhaust. Get a couple washers the same diameter as the width of the eye, and clamp them to the eye with a small bolt and nut. (effectively plugging the "eye"). Drill a small hole in the side or back of the header near the exit and slip the eye bolt's thread into it, and using two nuts on the thread, clamp it so the "lollipop" sits in the center of the exhaust pipe.

On my sportster this did wonders. Without it, the low end punch was noticeably weak and there was a big flat spot right around 3000rpm on partial throttle. The lollipop totally eliminated both. It has a decent baffling effect as well. I have a Sik Pipes header on mine, which is about as open and short as you can get, which of course was ear splitting loud. With an exhaust wrap and the lollipop it helped a lot. I mean it's still not exactly quiet, but well within what I think is tolerable.
 

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watches you sleep.
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Just putting drilled washers in your exhaust isn't going to quite it. All that will do is create back pressure. What you need is baffling and packing material to absorb the sound. I've seen an exhaust a guy made where He basically turned His midpipe back into one long muffler. He made a double walled long pipe section with baffling and packing in between them. That might be something to consider. You could also look at chopper mufflers. It won't quite your engine like a sportbikes muffler but it should help since they have packing in them. They're about $40 a piece. You're not going to find a muffler that quotes like a big cylindrical sportbikes muffler that's as small as a moto gp style or chopper/cruiser muffler unless you built it or give someone else build it.
 

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Is my bike ok?
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It doesn't have to be very big. Here's my first attempt at making a muffler. The whole deal ended up only being about 6''-8'' long. IIRC that header outlet I slid it in to was 2.5'' O.D. It was quiet enough that you could just hear the bike cruising at 65 mph ( ~ 6,000 rpm). but when you grabbed a handful it had a really nice roar.

Read to the end to see the different materials used. At the end of that thread I had used fiberglass weave for packing, but it didn't hold up very well. I ended up using regular old header wrap and it quietened the same and stayed on for a very long time.

http://honda-cb750-s.456789.n3.nabble.com/Homemade-muffler-using-stock-parts-td3420689.html
 
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A beetle baffle & a little packing will take the edge off the sound from that, it still wont be quiet but it will loose the raw edge, cost of the baffles hear is around £10 each proper packing is a £5

The reason its so loud in the first place is it was designed to replace the stock can on an modern injected bike that has a cat fitted which quietens the bike anyway
 

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UnicycleMode
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Never had any luck with those open pipes, they seem cheap and minimal. Hard to believe they charge as much as they do for them being you can get the same tube from an autoparts store and a clamp for less than $20, and paint it with high temp paint for less than half the cost of buying a premade one.



My brother and I have been building exhaust systems for a long time and his latest concept was a GP style shorty on his Bandit, baffled mid pipe (reworked stock unit) and a Vance and Hines megaphone muffler donated the rest of the bits that made it work out. The pics were taken before finishing was done to make it look really good, but overall it gives an idea of what it is. Probably the loudest I would ever go, but it does have an awesome sound to it.






And it ain't some pursuit of noise or styling either, this thing made better numbers than an unbaffled Yoshimura RS-3, and the previous Yosh mid pipe and R&D unit that was on it. 120+rwhp on this setup versus the 114 on the RS-3 and the 117 on the R&D. ;)

*edit* Those numbers are on open filters and alot of jetting corrections through a few hours of dyno time. With an exhaust you get what you pay for.
 
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