Another broken muffler! Options???

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I put a new set of mufflers from Commando Specialties on about two months ago and the left one has allready cracked at the where it slides onto the header pipe. I'm sure Duane will replace it but I don't want to deal with this every two thousand miles. I was carefull to mount them without being in tension & all the mounts are new. Are they all just junk? I would like to have a set of the stainless ones. Are they stronger & who's are best? Thanks.
 
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+2 the comment on the EPCO, u can get them off ebay if it suits from a company could stainlessride. Nice people to deal with and every now and then they have factoury seconds, that are still very nice, typicaly just a couple of slight ripples on the undersides. Sound is very deep ans not as blatty as the Emgo ones I had. Same trouble I broke about 4 muffler before getting the EPCO.

Cheers Richard
 
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The 75 850 header and mount system works great for me! Adjustable and no more lock ring!
 

maylar

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The weld at the pipe end is the classic spot for silencers to crack. This is the first time I've heard of Commando Specialties pipes doing that. Bummer :(

There must be some stress there that's not obvious, as this happens quite a lot. Even if you're anal about the mounting procedure like I am.
 
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The only real way of eliminating stress on the exhaust is to mount it to the cradle not the frame :mrgreen:
I know, not a helpful response. I've had lots of head pipes break but never a muffler.
 
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I did try to have the bolt holes all line up without stressing them into place. I'm wondering if there isn't something else contributing to the problem. My Iso mounts are not real bad and I'm using a head steady from CNW (thanks Jim.) I did want to go to a full stainless system so perhaps this is the Norton God's way of saying it's time. Thanks for the links guys. I just got home from 7 days of riding through the giant forest and surounding areas of Sequoia in California, glad it didn't happen on my trip. P.S. Are the stainless systems generaly stronger? Thanks.
 
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gtsun said:
Are the stainless systems generaly stronger? Thanks.

EPCO must use excellent manufacturing techniques. I always thought that stainless steel was more brittle than mild steel. The plus being that you'd never have to worry about rust.
 

nortonspeed

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ludwig said:
Another broken muffler! Options???

welding time again .
I think this time I'll make some reinforcement at the back ..

Ludwig, is that broken pipe (clamped on the exhaustpipe) just a short piece welded on, or goes that pipe all the way through welded to the conical end of your exhaust?
 
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Well at least the stainless ones can be rewelded & polished. Chrome ones will allways need rechroming if they crack. The Epco ones seem good but I'm looking around. The Keihan's are quite a bit cheaper ever with the currancy exchange rate for me in the U.S. Does anyone know who makes the ones that Commando Specialties sells & had experiances with them?
 
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Wes and I must ride miles of rough stuff each trip in and out to pavement. We have not yet had a silencer fracture its header end. Our fractures are all at the header flange end and the baffle tubes in the reverse cones. The Lords rubbers fail regularly too. I'm on hunt for flexible SS weave union such as used in marine and big trucks. This is not the coiled flex pipe as might be seen on classic exposed header cars. Trixie is stuck with factory weak warts but Peel gets reangled muffler support more 45" to get some weight bearing - bounce load in rubber compression-tension rather than pure shearing. On Trixie I order or make rubbers necked down so they don't resist motion and wear out before the metal.

To save the peashooters but stifle the annoying loud rattle of free baffle tubes I've drilled rear of muffler to place a lag bolt to trap the dang thing still though only half alinged with the entry-exit ports so half the exhaust bypasses baffle but I can't tell any effect on power or sound but thicker wallet slowing up acceleration a bit. You have to duck down and cock head to see the trap bolts. Mine just stick out 3/4" but could be trimmed to seat flush and less noticed.
 
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ludwig said:
nortonspeed said:
.. is that broken pipe (clamped on the exhaustpipe) just a short piece welded on, or goes that pipe all the way through welded to the conical end of your exhaust?

It is a tube about 10 cm long ( 4 inch for the metrically challenged ..) half in the muffler , half out ..

How is it supported inside the muffler? If it isn't I bet that's the problem.
 
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ludwig said:
swooshdave said:
..How is it supported inside the muffler? If it isn't I bet that's the problem.
You are probably right .
The inner tube of a std peashooter is welded at both ends of the muffler .
Mine isn't , because I made it so that I can take it apart for repacking .
But then , why do they crack also ?

That's a lot of weight hanging off the end and shaking. Pretty much guarantees something is going to break. Even mounted to the cradle your mufflers are still subject to shaking, just with less stress.
 
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I've tried to relieve some mass bouncing by some spring supports but it was hick scab on deal so didn't work out well for long but did imply could work out. hobot
 

nortonspeed

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ludwig said:
It is a tube about 10 cm long ( 4 inch for the metrically challenged ..) half in the muffler , half out ..

Ludwig, I had a similar cracking problem with my home made stainless peashooters. My mistake was I welded an one piece innertube all the way through and twice in a short period it cracked like yours. Then I welded in a two-piece (sliding fit with 4" overlap) innertube and had no more cracks ever since.
 
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ludwig said:
they never cracked ( ..but they are sooo heavy ..)

Weight dampens vibration. But you already knew that. If you want to go light you want to get the lightweight pistons to lessen the vibrations. That would probably keep the mufflers from breaking.
 
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