ZFD said:
Lots of these in the market, and many a nasty imitation where only the outside bears a resemblance to the real deal. however, the internals are crucial for the correct sound and performance. More on:
http://www.andover-norton.co.uk/Pirate%20Parts.htm
Toga used to do good ones (not anymore, I am afraid to say- the internals are now wrong). Campbells I gave up about 30 years ago due to their- then- VERY limited lifespan and tendency to fall apart at the mounting points.
Call it self-interest or call it experience, but my personal bikes have either vintage TOGAs or todays Andover Norton offerings on them.
ZFD,
From the link provided in your post above, the following information
about peashooter style mufflers is offered:
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The "Peashooter" Norton silencer.
Not a critical item one might think, and there are plenty of
offerings in the market. However, it is crucial to engine performance
to get the proper item. Andover Norton sells four different versions-
the seamless one in the picture, one with seams as on the 850s, one
with "Norton" logo and seams, and a special one with 1 1/2" (38mm)
inlet for specials and Triumphs. All of them are identical
internally.
The crucial feature are the internals. They must be absorption
dampers-. many cheap ones are labyrinth ones that you can't see
through- and, also very important, not only for sound but for
performance, it must have "flutes" in the internal through tube, not
a tube with holes. Anything but the original style internals will
decrease performance, even the production racers had the same
internals.
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Can you provide more information about the above prose, by replying
to the following?
What are absorption dampers?
Why are flutes important for performance? What performance are you
referring to? Sound dampening? Horsepower?
And "Anything but the original style internals will decrease
performance," that's a pretty broad statement. Is that just sales
hyperbole, or have you conducted some analysis you can share here?
Doesn't the Dunstall style of meagaphone, manufactured by so many
companies today, with almost identical dimensions and internal
construction as the original Dunstall mufflers, offer an alternative
to the peashooter without compromising performance? There's no
flutes in that design.
Also, I always wondered who would make a muffler with the Norton logo
stamped on the side, with the alignment being perpendicular to the
length of the muffler. I always thought that looked silly. It was
never something done on a factory bike. Campbells and Dunstalls both
had a tastefully done name stamp on the muffler, designed so the
alignment made sense when the muffler was fitted.
And lastly, for the sake of historical accuracy on this subject, I
have a friend who once owned a 1970 Roadster, and the peashooters on
that bike, which I believe were the stock mufflers, did not have
flutes, but a perforated pipe in the core. It had a wonderful sound,
being quite loud, with a good crisp bark and snarl between shifts.
Maybe someone on the board with an original 1970 S or Roadster will
chime in to shed more light on this.