Crooked exhaust baffle

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Can someone tell me how these are baffles installed and/or a good method to straighten the one that’s tilted in the right pipe? 75 Commando Interstate.

Crooked exhaust baffle


Crooked exhaust baffle


Crooked exhaust baffle
 
As far as I know they are welded in, how did it get bent like this?
Cheers
 
Hi Baz.
I’m just giving the bike a once over. Don’t have any history on it.
Weird that it doesn’t have any dents or other signs of damaged that caused this.
Best I can think of is to try and find a tube that will slide over the top of the tapered cone part and try and nudge it over.
 
The supporting structure of the 'intermediate' tube that the cap is fixed to has probably rotted away allowing the tube to flop over to one side.
Probably the only thing that can be done is to lever it back and jam something between the intermediate and outer tube to hold it in position as it's likely the rest of the internals are also rusting away and the only real answer is replacement.
 
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most likely you have an aftermarket type muffler and not the original type so anything goes on how they are put together inside. This is how the original Annular Discharge Silencers were made.

Crooked exhaust baffle
Crooked exhaust baffle
 
Thanks for taking the time to post those.
Yes, these do look different.
The black "cone" in the ones i have are tapered to the point where they meet inner wall of the external chromed pipe.
The cone on the ones I have also has six or so 1/2" holes about halfway up the taper where the exhaust is released.
 
This made me wonder what mufflers these are. In searching, I'm finding reference to -

part number 06-4170



06-4170 is the correct part number for 850 Mk1A, Mk2A and Mk3, also late Interpol......

https://andover-norton.co.uk/en/shop-details/16280/silencer-black-cap-

....although there is a 'straight-through' version available from RGM Motors....

https://www.rgmnorton.co.uk/buy/black-cap-silencer-straight-through-baffle-system_1262.htm

There was also a Triumph T160 Trident version 71-4402 but apparently the T160 Black Caps had different internals to Norton Black Caps.

https://www.britishbikebits.com/chrome-black-cap-silencers-pair-triumph-t160-trident

Edit: I forgot the 'black' JPN Black Caps 06-5948.
 
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"There was also a Triumph T160 Trident version 71-4402 but apparently the T160 Black Caps had different internals to Norton Black Caps"

Never heard that before!
I wonder if that's correct?
 
"NOTE: Later mufflers are stamped with the appropriate part number for identification."

Crooked exhaust baffle
 
Just an update. Was able to do some more work on the bike the other day and saw this on the right pipe.

Crooked exhaust baffle
 
Just an update. Was able to do some more work on the bike the other day and saw this on the right pipe.

Crooked exhaust baffle

Campbells* was a well-known manufacturer of replacement silencers.

*(Not to be confused with Campbell Geometrics that made performance exhausts)
 
Here is a picture of the muffler that came off my Mark IIA. Apparently the inner baffling had broken free and extended out of the muffler can about 2 inches. Fortunately, the baffling didn't come out any farther since this came out while riding and I was some distance from home. When this muffler failed, the motorcycle was only 20 years old and had less than 8000 miles on the bike. I replaced the mufflers with Roadster peashooter types from Fair Spares and I have been happy with those mufflers. They lasted over 25 years and the bike has over 25,000 miles on it.

Crooked exhaust baffle


I really don't know why I haven't thrown this muffler away. It really is no good!

Peter Joe
 
I really don't know why I haven't thrown this muffler away. It really is no good!

Peter Joe

Thanks Peter,
I probably wouldn't have tossed it either.
If you have the other side, I'm sure someone out there would have use for a set of the original OEM mufflers for the MKIIa. Even if one needs repair.

Ken
 
That can be repaired by someone with a good square wave machine if they were so inclined. I shake so badly now that TIG is only now a fading memory in foggy daydreams.
 
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