SOB broken headers!

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I purchased these silencers from AN and since I have so few miles on them, I wonder if they'll send me a free replacement. It looks to me as if it broke on the weld. I'll give them a call and see what my options are.
Were they under any tension at all when you fitted them?
 
Were they under any tension at all when you fitted them?
The pictures do suggest that.
As does the fact that both the header and silencer split.
Having a rubber mounted engine and solid mounted Z Plates means Commando exhausts don’t have the easiest life. Very careful assembly is therefore crucial IMHO.
 
I would guess that AN would want to see the silencer first if there's any suggestion of defective workmanship, but if you'll pardon the pun, I reckon you're on shaky ground, given the DIY nature of the item sold and the environment it works in...
And as the pipe has cracked too, it does point to an assembly problem, as many have suggested
 
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Any crack likes to have somewhere to start
The edge of a weld is ideal
 
I'm up for a new set of pea shooters every time I find a set to use you guys post pics of broken mufflers from the guys I'm thinking of buying from. Please help is there anything out there that doesn't break in half.
Hard to answer
The stainless steel ones from rgm seem hard to break so far
As are the stainless ones from armour's but the armour's type have an annular discharge type baffle
The RGMs have a perforated tube wrapped in wadding
 
I purchased these silencers from AN and since I have so few miles on them, I wonder if they'll send me a free replacement. It looks to me as if it broke on the weld. I'll give them a call and see what my options are.

From the angle of the tube in your pictures, it looks to have either broken internally as well or is only a short section of tube because I would've expected that tube to extend almost to the rear end of the silencer as below?

SOB broken headers!
 
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Okay - go with me here...
There's a thing that I do that is because I'm a bit anal about preventing fatigue cracks in the exhaust system
I don't have a balanced system (so, less prone) but, nonetheless...
When I have returned from a ride and the bike is still "warm" I use a cotton rag and grab the rear of each peashooter and "wiggle"it about. If I hear any noise it is generally an indication that a pipe-to-muffler clamp needs tightening. I do that and - violet (or whatever) - no noise.
Most times there is no noise - but I do it anyway.
My background as an engineer leads me to believe that "noise" (unwanted HF movement) while riding will be a cause of the killer fatigue.
People and time may judge me to be incorrect, but I think it's worth doing
Cheers
 
Okay - go with me here...
There's a thing that I do that is because I'm a bit anal about preventing fatigue cracks in the exhaust system
I don't have a balanced system (so, less prone) but, nonetheless...
When I have returned from a ride and the bike is still "warm" I use a cotton rag and grab the rear of each peashooter and "wiggle"it about. If I hear any noise it is generally an indication that a pipe-to-muffler clamp needs tightening. I do that and - violet (or whatever) - no noise.
Most times there is no noise - but I do it anyway.
My background as an engineer leads me to believe that "noise" (unwanted HF movement) while riding will be a cause of the killer fatigue.
People and time may judge me to be incorrect, but I think it's worth doing
Cheers
I don't use any silencer pipe clamps
 
Hard to answer
The stainless steel ones from rgm seem hard to break so far
As are the stainless ones from armour's but the armour's type have an annular discharge type baffle
The RGMs have a perforated tube wrapped in wadding
There are also the stainless ones from Keihan systems, I think Feked are resellers for these aswell .
 
I've not seen those
I'd imagine they are quality items?
They seem to be yes, I know BMW owners who have them and they are extremely pleased, expect the same with Norton owners but I don't actually know any that have them. they seem a really good price and Keihan will polish them up again after a few years use
 
The pictures do suggest that.
As does the fact that both the header and silencer split.
Having a rubber mounted engine and solid mounted Z Plates means Commando exhausts don’t have the easiest life. Very careful assembly is therefore crucial IMHO.
In the pictures I took I intentionally pulled the silencer away from the header and away from the mount to show the damage. I mounted both halves of the exhaust system in exactly the same way. I aligned the headers, tightened the rose nuts then installed the silencers and clamps. All were under zero tension. Lastly I installed the balance tube and clamps. It was a thirty mile ride home after I discovered the broken silencer and during that time the header cracked and just got worse the more I rode. You can bet your ass I’m going to pay particular attention when I install the new exhaust system. In fact I think I’ll video the procedure just for fun.
 
From the angle of the tube in your pictures, it looks to have either broken internally as well or is only a short section of tube because I would've expected that tube to extend almost to the rear end of the silencer as below?

SOB broken headers!
The tube is broken internally. I can almost pull it out of the silencer except for something hanging up inside.
 
With balance pipe exhausts you need to modify the silencer mounting brackets. The balance pipes have the kick at the end soley for the black cap silencers, which mount in a slightly different position.


I assume you mean 850 Mk1A, Mk2A and Mk3 "balance pipe exhausts" for black caps as 850 Mk1 and Mk2 had peashooters with balanced exhaust pipes but not the same parts?

AN currently lists the Mk3 (thus black cap) pipes for all 850s as AN's 850 Mk1 and Mk2 spares diagrams show standard peashooter silencers but with "Item 1" links to the Mk3 pipes!
850 Mk1
850 Mk2

No mention of the Mk3 pipes not only being unsuitable without modification of the mounting brackets but that black cap brackets ("06.4148, 06.4149 & 06.4150") are "required" regardless of them being unsuitable for mounting peashooters!

SOB broken headers!


(The AN Mk1A and Mk2A diagrams still have the same black cap silencer mounting bracket errors!)
 
I like the mod concours did a few years ago. He made up brackets which helps take some of the load away from the downpipes and the rubber mounts.


(scroll down)
 
I like the mod concours did a few years ago. He made up brackets which helps take some of the load away from the downpipes and the rubber mounts.

Unfortunately, due to the Mk3 primary chaincase, such a bracket can't be fitted on the LH side.
 
Hi Guys I have / am completing a Mk3 rebuild using balanced headers from Andover and "peashooters", I have used the earlier 750/850 muffler mounting plates and there is no apparent tension problems, prior to purchasing the Mk3 I had a Mk2A for about 12 years which was also fitted with balanced headers and peashooters using the earlier mounting hardware and never had a problem.
 
Thanks L.A.B. Good to know.

It might just be possible if the arm had a dogleg in it to get over the frame tube and then under the chaincase and it would need to be about 4 inches in length to reach the exhaust pipe so I don't know how much useful support that would provide?
 
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