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Discussion Starter #1
how exhaust may work-tuning of exhaust, etc

I dont know if there are any good books but if you should find one pass
along the info.
my understanding is just from the car racing I have been exposed too.
my thoughts are as follows:
when the exhaust valve opens and the gas is leaving down the tube it is hot
and many times its normal volume due to expansion by the heat. as it travels
down the pipe, it creates a vacuum at the valve area when the gasses have
left at a high velocity. then the valve closes with the vacuum intact, this
is a perfect exhaust system.

unfourtunatly we put things into the picture that disturb this, like
mufflers and odd lengths of pipe not tuned to the proper length needed to
create the scavenged effect, like car headers work.

the muflers on the bike have a restriction and the wave of gasses, a
shockwave if you will, hit the muffler and tend to bounce back, if they get
back before the valve closes, you may get some back in your cylender.

This is where the expansion chamber comes in, the exhaust shockwave coming
from the head pipe filles this chamber and is allowed to expand and cool to
a smaller amount, not hitting the muffler baffeling and returning.

This is why I added the H-pipe, it allows the gas expelled from cyl 1 to go
int cyl 2's pipe when it is not in use and escape and cool there too. then
when 2 fires, it can go into cyl 1.
this gives you a virtual chamber, plus 2 outlets instead of just one.

Just my out of the box thinking.-may not be right, but Im going with it for
until Im taught different.
beavis

-Beavis
God bless, The best safety equipment is to pray regularly, ride Safe
see my pictures and modifications at:
www.fortunecity.com/bennyhills/radner/499
----- Original Message -----
From: "Michael Smith" <[email protected]>
To: "beavis at home" <[email protected]>
Sent: Tuesday, July 27, 2004 12:45 PM
Subject: Re: Ear Shave - Goats Belly...


> Hmmm...I'll have to read some books on the physics behind exhaust sytems -
> things still aren't adding up in my mind. I would defiantly post
> this..contributing to these sort discussions bears no risk but can yield
> enlightenment.
>
> ----- Original Message -----
> From: "beavis at home" <[email protected]>
> To: "Michael Smith" <[email protected]>
> Sent: Tuesday, July 27, 2004 10:01 AM
> Subject: Re: Ear Shave - Goats Belly...
>
>
> > Thats what they say, that the goat belly is helpful for low end torque.
> but
> > the H-pipe added to the degoat allows the exhaust to find 2 outlets
> instead
> > of just one, plus more area inside for the exhaust to cool to exit in
less
> > of a mass. this is why I think the goat helps you, as it gives you acess
> to
> > both pipes from either cylender. removal means you only have the short
> lent
> > of pipe with the restrictive outlet in the stock muffler, that you need
> > unless you want to give the harleys a run for the money on loudness,
LOL.
> if
> > you did remove the mufflers as well, I think that would give full power.
I
> > dont think you "want " backpressure like some believe. I cant imagine
why
> > you would want exhaust left in your cylender, however, exhaust left in
> your
> > cylender does add to the octane quality of your fuel, so you may
concider
> > running 89 instead of 87, if you notice any pinging. but this should
yeld
> > more power, since you have more room for fuel and air, not spent gasses
in
> > the way.
> >
> > maybe we should post this?
> >
> > -Beavis
> > God bless, The best safety equipment is to pray regularly, ride Safe
> > see my pictures and modifications at:
> > www.fortunecity.com/bennyhills/radner/499
> > ----- Original Message -----
> > From: "Michael Smith" <[email protected]>
> > To: "beavis" <[email protected]>
> > Sent: Tuesday, July 27, 2004 10:58 AM
> > Subject: Re: Ear Shave - Goats Belly...
> >
> >
> > > Beavis,
> > > Checked out your website...you mention that the degoating process saps
> the
> > > bike of power?? I don't understand. My thoughts were that since I
> > removing
> > > a restrictive device from the exhaust - the engine would experience an
> > > increase in proformance.
> > >
> > > I'm all ears,
> > > michael
> > > ----- Original Message -----
> > > From: "beavis" <[email protected]>
> > > To: "smithmichaels" <[email protected]>
> > > Sent: Tuesday, July 27, 2004 4:58 AM
> > > Subject: Re: Ear Shave - Goats Belly...
> > >
> > >
> > > > I haven't done the ear shave "yet" so I haven't re-jetted. I hear
the
> > most
> > > > trouble is with not putting enough spacers behind the needle that
> comes
> > > with
> > > > the jet kit.
> > > > sorry I couldn't help, but plan to do that one day.
> > > > Thanks,
> > > >
> > > > Beavis
> > > >
> > > > Ride Safely. The best safety equipment is prayer.
> > > >
> > > > see my pics and mods at:
> > > >
> > > > www.fortunecity.com/bennyhills/radner/499
> > > > ----- Original Message -----
> > > > From: "smithmichaels" <[email protected]>
> > > > To: <[email protected]>
> > > > Sent: Monday, July 26, 2004 3:18 PM
> > > > Subject: Ear Shave - Goats Belly...
> > > >
> > > >
> > > > > Hey buddy,
> > > > >
> > > > > What size jets are you running? I just finished doing the ear
shave
> > > > > and taking the EPA stuff out as well as the goats belly removal
> > > > > (stock pipes) but am having a heck of a time finding the correct
> size
> > > > > jets.
> > > > >
> > > > > Thanks
> > > > > Michael Smith
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
 
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