Armours fishtail exhaust

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T Batnes
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Armours fishtail exhaust

Postby T Batnes » Tue Jan 21, 2020 11:32 am

I will put an Armours fishtail on my upsprited 350 with a Franklin P2 cam and a 7,5:1 piston.
It will be a single port head on it after all, so all the exhaust have to go through this fishtail, and when I look inside, I am a little baffled by the baffle plate.
It looks restrictive. What would you do?
1) Drill away the baffle plate totally? Noise?
2) Perforate it with a 1/4" drill, to reduce it by 50%?
3) Knock it back 45 degrees with a chisel or a roundbar at the sides, where it is not spot welded to the pipe?
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Re: Armours fishtail exhaust

Postby JohnnyBeckett » Tue Jan 21, 2020 6:47 pm

HI I Would drill holes in the plate my box has not got a plate in the bottom of my exhaust box it is straight through

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Re: Armours fishtail exhaust

Postby alan.moore » Tue Jan 21, 2020 9:59 pm

Is the fishtail bit more restrictive then the baffle which is at least 30% holes?
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Re: Armours fishtail exhaust

Postby john.whiting » Wed Jan 22, 2020 12:55 am

Cops here would pull you over and poke a rod down the muffler....if it didnt hit a stop before it went to the depth of the muffler,they would kick the bike over on its side ,and plant one boot on the tank ,and use the knee as a rest to write you out a ticket for defective exhaust,and anything else took their fancy.

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Re: Armours fishtail exhaust

Postby JohnnyBeckett » Wed Jan 22, 2020 7:12 pm

that's why i would just drill holes in the plate so a rod will not go right through :!:

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Re: Armours fishtail exhaust

Postby paul.jameson » Wed Jan 22, 2020 7:59 pm

I have fishtail silencers from the Czech boys on my Square four. These have no baffles whatsoever in them so I have fitted Armours "pepperpots" in the ends of the exhaust pipes. These "pepperpots" are very similar indeed to the baffles in your silencer. The Square goes very well indeed but it is two 250cc cylinders per exhaust as opposed to one 350cc cylinder.
Given the length of the "pepperpot" and the number and diameter of holes in it I would suspect that it has a similar total flow area to that of the exhaust pipe. Clearly, the smaller holes at right angles will hamper gas flow but to quite what extent is a good question.
I would suggest fitting the silencer as it is and seeing what performance is like. Then, one day, take the silencer off and see if performance is any better. If the cops catch you without the silencer fitted, I would suggest that the difference in performance is not enough to be worthwhile.
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