PT: Exhaust Norvin - Exhaust System

John Cone

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I ordered a stainless system for my enclosed "D" from Armours. There was no way they would fit around my built in crash bars. They were pretty good, i have sent it back along with my originals for them to copy, hopefully they'll get the front pipes right.
 

Rixon

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Bought a stainless goldie silencer from Armours, looks good and is of the straight-through absorption type. They make them to fit a Norton and they have much neater mounting points than the original BSA design.

Also got the pipes from Armours, unplated. I'm not quite so impressed, but we will re-weld them ourselves and grind out the excess material (overlap) where the pipes join, before sending them back for chroming.

I've attached a picture of the original pipe for comparison.

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PipeOverlap (1500x1145).jpg



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b'knighted

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I have one of their stainless “goldies” on my big Comet. It has the most anti-social raucous bark and will drown out the feeble sound of Harleys. I love it. The two tapped mounting holes permit the most ridgid bracket I’ve ever had on a Vincent.
 

timetraveller

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Your second photo shows a fault that I had on a pair of s/s Armours twin pipes. They had not made the hole in the long pipe large enough diameter to let the gas out of the rear pipe, in my case the hole was about 3/4" diameter, In your picture it looks as though they have left a step of perhaps 1/4". I used a solid carbide bur in a die grinder to sort mine out.
 

Bill Thomas

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Bought a stainless goldie silencer from Armours, looks good and is of the straight-through absorption type. They make them to fit a Norton and they have much neater mounting points than the original BSA design.

Also got the pipes from Armours, unplated. I'm not quite so impressed, but we will re-weld them ourselves and grind out the excess material (overlap) where the pipes join, before sending them back for chroming.

I've attached a picture of the original pipe for comparison.

View attachment 35819View attachment 35820


View attachment 35823
Maybe some of that would be polished out before chroming ?.
 

Rixon

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Even with polishing I wouldn't be happy with that welding (i'm a fussy bugger!) and as a previous poster has mentioned, the hole in the main pipe isn't cut large enough. Actually it probably is cut large enough but the two pipes aren't aligned correctly. The die grinder will indeed be coming into play. I imagine the original pipes were brazed.

I've no doubt Armours would sort it out if I went back to them (they are amazingly pleasant and
20200617_135513 (1500x911).jpg
helpful people) but I do think the product could be a bit better.

Misalignment shown in the picture.
 

John Cone

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VOC Member
I ordered a stainless system for my enclosed "D" from Armours. There was no way they would fit around my built in crash bars. They were pretty good, i have sent it back along with my originals for them to copy, hopefully they'll get the front pipes right.
I have at long last received my new stainless exhaust from Armours after sending them my originals as patterns. They still took a little fettling but not much and look pretty good. Now i have fitted them i have agreed to send my old ones back to Armours to use a patterns. So anyone wanting a stainless exhaust specifically for an enclosed "D" now knows where to find one., although they should fit B's and C's as well.
 

Monkeypants

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Non-VOC Member
Going back to the diameter question, I recall mulling this over before building an exhaust for the 1360. I used 2" on that after plugging the numbers into the calculators.
There are several online calculators for this. The three I used all stated 1 5/8" OD (with .080" wall) as optimum diameter for a 998cc bike using 5800 rpm as max. So yet another thing that Phil Irving had right.

Glen
 

davidd

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VOC Member
The first photo in post 62 shows a weld that looks very hot, but when you look at the second photo you can see what went wrong. The weld was done with no back purge of argon. A weld that has no back purge tends to run hot and it concaves. If you look in the pipe you can see all of the "sugaring" you get when you do not purge the inside of the pipe with argon.

If you back purge, then the weld on the inside should be smooth and silver.

As Glen says, the diameter of the pipe is correct for the cams available from the Factory. The Gold Star testing is a good place to get information on the various straight pipe and megaphone sizes.

David
 
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