Inside Anders' lozenge muffler / silencer

[roadplough]

Thanks to Anders Palm for these photos.
Anders found a thread where I expressed an interest in what's inside the lozenge - interesting for sure..





And this is a good looking bend..
Anders have you considered changing the angle of the exit pipe a little bit while you're at it?
If it was pointed down by a few degrees it would then not be pointing at where the blinker normally goes - black with soot.





very interested to know how this mod works and sounds...

[roadplough]

from Anders: "I have an mx cam and a 34 mm Amal MK2 carb,it become a great difference in
performance with the new muffler.I don’t think that it is to loud,no horses
is run away,and it was a way to keep the black-box muffler that I like.This
was the last picture.
Anders."

[roadplough]

That's odd, they appeared for me.
I've changed the original file names so if they work now it might have been something to do with having international english enabled..

Anders, I see your tail pipe now.
(I posted the first lot of pics before noticing my emailer had gagged halfway through the download, hence the 2 postings above)



I also added a piece of pipe but at the same diameter as the standard exit pipe, I'm sure it saps some power. Certainly silences a bit more.

[beat]

vergot to ask : what inside diameter are on this tubes you have been taking outh of the muffler ?
beat

[Anders Palm]

Hi beat.
I dont think that the horses in Sweden hear so good.I have measure the pipes that was inside the muffler,the short ones to the right is 20 mm inside ,and the other is 23 mm inside.This was a 250cc muffler,I dont know if the 500cc is the same.
Anders Palm.

[beat]

thank Anders.

it would be interesting to know the pipes diameter of a 500 as well.
if I got it right : falowing the direction of the gases, the first tree pipes are the shorter ones and also the smaler diameter. right ?
as they have a surface of 943 mm2, it would corespond with one single hole of abouth 55 mm on the smalest part I guess.
that says to me, BSA let this litle engine breath quite well !
beat

[Anders Palm]

Hi beat.
The outlet from the muffler is to the right,I have measure the three
short pipes on my 500cc muffler,from the end of the muffler,and they have the same diameter as the 250cc,and also the outside outlet-pip
has the same diameter.
Anders.

[Canberra]

The parts numbers on Rickard's database show the following numbers for what appears to be outwardly the same silencer.

B25H (1971) - 71-2400
B25T+SS (1971) - 71-2411
B50H (1972) - 71-1711
B50T+SS (1971 and 1972) - 71-2401

My 1971 part book nominates
B50H (1971) - 71-2412

Any views on the differences?

I am unsure of the header diameter and if they vary then that may explain different B50/B25 numbers.

I wonder why the different silencer on the H model? Maybe the sound was altered to make it less obtrusive to non British ears? My B50SS was purchased in UK and nominated as a SS but had B50H components and it seemed to perform better than standard SS from new. It rev'd very freely.

I guess the silencer (muffler to the Americans) internals would have been different.

John

[HPbyStan]

B25, inch 3/8 dia head pipe
B50, inch 1/2 dia head pipe

[beat]

B25 is -35 mm
B50 is -38.2 mm
and 55 mm is abouth the smalest diameter inside the Muffler.hm hm hm
I know, it is not only the smalest diameter responsible for the mufflers resystance, but it says something....
as I chosen 45mm in square, it makes 2025 mm in compare to ab. 950 I guess I can sleep quite well tonight.. ore did I miss something ?
beat