Author Topic: Modifications to standard mufflers  (Read 316 times)

MikeScoot

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Modifications to standard mufflers
« on: February 06, 2020, 03:47:10 AM »

 I'm toying with the idea of doing some sort of mod. to my standard mufflers to increase their dB a little. I'm thinking something easily reversible would be good for times when levels might need to pass certain tests.

Does anyone know much about the internal structure of the mufflers? Drawings perchance?
Luther had his dream,
But I've got my Vision.
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Prophet Of Doom

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Re: Modifications to standard mufflers
« Reply #1 on: February 06, 2020, 08:12:54 PM »

What condition are they in?
If they are sparkly I'd consider swapping them for a set of brand new macs - that would give you some VOLUME.  Freight not too bad across the ditch

MikeScoot

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Re: Modifications to standard mufflers
« Reply #2 on: February 06, 2020, 10:49:29 PM »
They are in good pretty good nic with no rust BUT one has a large, but well done, patch over some crash damage. I had them sent over from the States at considerable expense, so they'll stay on this bike. Sorry.
Have you ever chopped a muffler? Do you know the baffle construction? If you have a rusty one maybe you can see in there a bit. I'm particularly interested in the last 50~100mm of the muffler.
« Last Edit: February 07, 2020, 02:46:51 AM by MikeScoot »
Luther had his dream,
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His got him into strife,
Mine just takes me fishin'.

auto

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Re: Modifications to standard mufflers
« Reply #3 on: February 07, 2020, 12:27:14 PM »
There is a cut away view of the vision on the internet.It kind of shows the baffling in the pipes. I have a set that I'm going to experiment with. Was looking at cutting out the end plate with a large whole saw. then see what can be done to remove some of the baffling.

MikeScoot

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Re: Modifications to standard mufflers
« Reply #4 on: February 07, 2020, 02:17:50 PM »
Ah! That's pretty much what I was thinking. It would be nice to have a couple of sets of interchangable baffles.
I'll have a look for that cut-away.
Cheers
Luther had his dream,
But I've got my Vision.
His got him into strife,
Mine just takes me fishin'.

MikeScoot

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Re: Modifications to standard mufflers
« Reply #5 on: February 07, 2020, 11:07:44 PM »
Found a cutaway. Don't know whethet it's the same as the one you saw but it"s named "Jellyfish" and is in the resources section at the top of this section.

Appears one end of a final tubular baffle is tucked and welded into the flat end of the muffler. Not sure about that baffle's other end. It may not be welded. In that case the baffle would slide out. If not then half a dozen holes could be cut into the end plate between the weld that holds the baffle and the outside rim of the muffler. Another plate could be made to cover the holes when less music was desired.
Luther had his dream,
But I've got my Vision.
His got him into strife,
Mine just takes me fishin'.

auto

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Re: Modifications to standard mufflers
« Reply #6 on: February 09, 2020, 09:07:09 AM »
There are a whole lot of spot welds to deal with.Thats why I going try to open up a junk exhaust. There out there.Last week at the York swap meet could picked up a parts vision for $30.If I had my trailer would of got it.

injuhneer

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Re: Modifications to standard mufflers
« Reply #7 on: February 10, 2020, 09:00:13 AM »
I too have been looking at the exhaust.

The SuperTrapp Slip-On for Vmax looks promising with some fabrication. Otherwise I was considering cutting out the end then making and adapter to switch out baffles. Much on the order of what MikeScoot described.

The diffuser discs are plentiful and there are several universal SuperTrapp mufflers that might be interesting.
- Mike O
injuhneer
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1978 Kaw KM100
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injuhneer

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Re: Modifications to standard mufflers
« Reply #8 on: March 22, 2020, 09:40:56 AM »
Found a cutaway. Don't know whethet it's the same as the one you saw but it"s named "Jellyfish" and is in the resources section at the top of this section.

Appears one end of a final tubular baffle is tucked and welded into the flat end of the muffler. Not sure about that baffle's other end. It may not be welded. In that case the baffle would slide out. If not then half a dozen holes could be cut into the end plate between the weld that holds the baffle and the outside rim of the muffler. Another plate could be made to cover the holes when less music was desired.

Or you could make it like a vent (think barbecue grill) that could be rotated to open/close.

- Mike O
injuhneer
1982 Yamaha XZ550RJ
--------------------------------------------
1975 Honda ST-90 (164cc stroker)
1972 Kaw GT4R
1978 Kaw KM100
2008 KTM 450 SXF

jefferson

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Re: Modifications to standard mufflers
« Reply #9 on: March 22, 2020, 09:49:04 AM »
The supertrapp conversion has been done many years ago. The editor of the club newsletter at the time did a writeup in the newsletter about it. I'm pretty sure there are copies of the newsletters on here that were scanned and uploaded.

MikeScoot

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Re: Modifications to standard mufflers
« Reply #10 on: March 23, 2020, 04:47:24 AM »


Or you could make it like a vent (think barbecue grill) that could be rotated to open/close.

What a great idea! :-) :-) :-)
Luther had his dream,
But I've got my Vision.
His got him into strife,
Mine just takes me fishin'.

Kenny

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Re: Modifications to standard mufflers
« Reply #11 on: March 23, 2020, 07:05:34 PM »
  One suggestion I had heard of for an R series BMW was to get a drill extension with a bit that will fit through the exhaust exit and drill a hole through the inner casing (baffle) this will allow for more air flow and noise.
         Cheers Ken ;) 
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MikeScoot

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Re: Modifications to standard mufflers
« Reply #12 on: March 24, 2020, 04:10:31 AM »
I suppose that would be a fast and easy way to go about it. Swarf might kick around a bit in there but eventually find its way out the exit - or be shaken out the other end.

Injuhneer's suggestion about a BBQ-style solution sounds particularly interesting. Not sure whether I interpreted it correctly but I'm thinking an arrangement where one of two adjacent flat disks could be rotated to enable selection from a variety of sets of different size/shape exit passages/holes.

The mind boggles. :-)
« Last Edit: March 24, 2020, 04:14:53 AM by MikeScoot »
Luther had his dream,
But I've got my Vision.
His got him into strife,
Mine just takes me fishin'.

injuhneer

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Re: Modifications to standard mufflers
« Reply #13 on: March 24, 2020, 03:27:15 PM »
I suppose that would be a fast and easy way to go about it. Swarf might kick around a bit in there but eventually find its way out the exit - or be shaken out the other end.

Injuhneer's suggestion about a BBQ-style solution sounds particularly interesting. Not sure whether I interpreted it correctly but I'm thinking an arrangement where one of two adjacent flat disks could be rotated to enable selection from a variety of sets of different size/shape exit passages/holes.

The mind boggles. :-)

 ;)

Variable exhaust, baby.
- Mike O
injuhneer
1982 Yamaha XZ550RJ
--------------------------------------------
1975 Honda ST-90 (164cc stroker)
1972 Kaw GT4R
1978 Kaw KM100
2008 KTM 450 SXF

MikeScoot

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Re: Modifications to standard mufflers
« Reply #14 on: March 24, 2020, 09:56:44 PM »
lololol Might be able to set it up so a skilled pillion could reach down and make it whistle Dixie!
Luther had his dream,
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His got him into strife,
Mine just takes me fishin'.

cafevision

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Re: Modifications to standard mufflers
« Reply #15 on: March 31, 2020, 09:54:43 AM »
I did the long drill bit extension with a 5/8" [i think] on my first vmax. Sounded good but I later bought a custom system by Mark's exhausts. He was an engineer for kerker and makes them for vmaxs in stainless or ceramic coated steel with custom length mufflers and baffle cores.