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I am about to embark on the gutting and modification of the stock silencer as inspired by Ralphus. Having never attempted anything remotely like this before, I would appreciate any advice or wisdom you may have.

I do have a few questions right off the start. What kind of glass pack should be used? Is there away to rebuild the silencer for future repacking or do I have to weld it shut?

Thank you.

http://www.triumphrat.net/memberalbums/showphoto.php/photo/8820
 

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955 or 1050?:confused:

If you put your bike in your sig under "favourite bike" it makes it easier for other posters when answering your questions.

If it is the 955 I know there are several threads about boring a large whole through the centre of the can.

If it is the 1050 underseat muffler there is also a thread about that showing it all disected.

Cheers,
DaveM:cool:
 

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Its there but in disguise..... 007 Phantom Black.... or a 07 Phantom Black. :)

You will have to weld it shut or it will leak.
 

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What kind of glass pack should be used? Is there away to rebuild the silencer for future repacking or do I have to weld it shut?

Thank you.

http://www.triumphrat.net/memberalbums/showphoto.php/photo/8820
I just used some generic muffler packing glass from a motorcycle shop.

I welded mine shut figuring it would be a long time before I would ever need to think about repacking it. My pipe has 2 layers of fibreglass packing: the original packing between the inner and outer skins, as well a layer between the pipe and the inner skin.

My pipe is only slightly louder than stock and quiter than the Triumph TOR can. I expect that it will get louder over time.

You could pop rivet a lid to the top if you wanted to repack it.

I have some alternative designs that I was playing around I would be happy to email you if you want PM your details.

Good Luck
 

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A few conceptual designs

Here's a few sketches I messed around with. If you want the maximum performance the first one is the best because there is very little restriction to flow. I am pretty sure I used 45mm perforated tubing on my muffler, the yellow areas are where the fibreglass packing goes.
 

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Ralphus,

After looking at all four, I was wondering if you thought the Boom Box one would provide just enough back-pressure to keep the low end running smoothly? I don't know anything about this stuff but I do remember reading if the pipe is too open, you can lose smooth power on the bottom end.
 

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Ralphus,

After looking at all four, I was wondering if you thought the Boom Box one would provide just enough back-pressure to keep the low end running smoothly? I don't know anything about this stuff but I do remember reading if the pipe is too open, you can lose smooth power on the bottom end.
I'm not suffering any loss of torque down low after modifying the muffler to a straight through design and downloading the TOR, in fact my butt dyno thinks it is actually stronger and smoother in the low to mid range than the stock set up.

The TOR tune is probably the thing that has smoothed it out the most because it addresses the usual emissions driven issues of leaning out the bottom end.
 

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Discussion Starter #9
Thanks for that Ralphus :) Your photo shows a minor S curve in your modification somewhat like the 3rd design but without the extra connections to the two outboard outlets. Apart from the back pressure wave created at the 3 into 1 collector, I wonder if that small bend also creates some back pressure. I recall Wolf mentioning a small change to his Trident design where a 1/2 inch reduction to the diameter creates some back pressure and helps in the midrange (http://www.triumphrat.net/sprint-forum/97479-trident-exhaust-owners.html).
 

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Thanks for that Ralphus :) Your photo shows a minor S curve in your modification somewhat like the 3rd design but without the extra connections to the two outboard outlets. Apart from the back pressure wave created at the 3 into 1 collector, I wonder if that small bend also creates some back pressure. I recall Wolf mentioning a small change to his Trident design where a 1/2 inch reduction to the diameter creates some back pressure and helps in the midrange (http://www.triumphrat.net/sprint-forum/97479-trident-exhaust-owners.html).
You're right my muffler does have some small bends in it.These do impact on the flow of the muffler which will create some minor amount of back pressure. I tried to keep the pipe cross section the same all of the way through to limit the amount of turbulence.

The Trident and IXILs are a compromise because they aim to give good aesthetics with the three pipes as well as improved performance. Bends and changes in cross section do not help flow. If they were going to make a race muffler it would most likely resemble the Two Brothers Muffler in design which in my opinion is not the best aesthetically but effective none the less because of its straight through design.
 

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A couple of quick questions on this topic guys. I just got hold of a used stock muffler to do this on so my bike stays on the road.
It looks like the muffler is double-skinned with insulation between skins. Does this mean that you have to weld the inner skin back in first, then repack with insulation and then weld the outer skin back on or do you just do the outer skin?
 

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Thanks Dave.
I think I've read just about every thread on this subject, with Ralphus's threads showing some photos and another member (can't remember his name) also chiming in as well with a pic or 2.
However , no-one has specifically discussed this step and it's only something I've picked up on from some descriptions and a closer look at the photographs.
The other issue is that I think the guys that have done this mod have had the welding done by a pro or a shop. I am definitely neither but I'm going to give it a shot.
A heads up on this would be really handy before I cut the top out of it.
COOOOEEEEEE!!!
 

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The inner skin should be tacked back together after the inner cavity has been stuffed with packing material. Then the insulation between the inner and outer skins should be put back in place and finally the outer skin welded back in place.
 

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Not to interrupt this fine conversation, but I found it a whole lot easier and less technical (albeit with the tools I have laying around already) just to punch holes in the stock muffler with it on the bike. As long as you get the entry angle right, you can drill straight through the cat to the open chamber at the front and get a really nice tone. Got no clue about the dyno difference, but I'm sure it's no worse at any point in the RPM range.
Since I have no welding skills and didn't want to buy any supplies at all, I just grabbed my cordless drill and a handfull of bits and went to town with the old fashioned mufflerectomy. Once I got the initial holes punched ( and I say punched, because you really can't drill through a catalytic converter) I rode for a few days and figured I wanted it a little more agressive sounding. Grabbed a 1/16 larger bit and enlarged the holes. Repeated over several weeks- since there's no going back- and stopped somewhere around 3/4". I've not heard another 1050 with the exhausts you all have talked about, but it sounds much stouter than the stock did and isn't obnoxious at all. It really shines during a lower RPM roll on- has this great throaty ripping sound, like it's going to shred the asphalt and everything in the vicinity.

That's my 2 cents.
 

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I used a simplified version of the Ralphus method. Rather than installing a perforated pipe and additional packing, I just completely gutted the stock can, including trimming the bends in the two outer exit pipes. Reassembly included tacking the inner perforated skin back in position, installing the original insulation and welding up the outer skin. It cost me $40aust to have the aftermarket tune loaded. I've been very happy with the result, a noticable increase in torque and a great note.:D
 

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Thanks for that clarification Ralphus, I was hoping you'd hear the call.
Thanks also Alan for your input. I had already read your post in the other threads. Luckily I have access to plasma cutters, TIG welders, grinders, drills etc. and I have a spare muffler from a fellow trumpeter. Also, our bikes don't have CATS. So I will give it a go and see if I can maybe refine the process a bit.
Thanks also GM your mod definitely sounds interesting.
But being the tortured perfectionist I am, I'll go with Ralphus's mod with maybe a bit more solid pipe and just perforated for the mid-section. I may also hang back a bit on the packing.
Already got TuneEcu running and the TOR map saved ready to go.
Stay tuned folks.....
 

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One last question mainly directed to Ralphus....
Would you say it has gotten louder since you did this mod?
I'm trying to guage how much insulation packing to put back in there.
 

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One last question mainly directed to Ralphus....
Would you say it has gotten louder since you did this mod?
I'm trying to guage how much insulation packing to put back in there.
It is only slightly louder than stock because there is such a large volume of packing around the inner pipe. I would still pack it with as much packing as you can stuff in there. It will eventually blow out and slowly get louder.

If you want a louder pipe use more plain tube instead of perforated tubing.
 
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