AAAAARRRGGGHHHHHHH!!!!!!!
*running from computer pulling out hair*
the reduced back pressure causes a more free flow in the system thus causing
an improved scavenging from the cylinder upon exhaust stroke. not all
unburned mixture is exhausted upon each exhaust stroke. but with less
restriction, more than there was, is being extracted. now with less
residual mixture in the cylinder to mix with the new intake charge it will
be leaner in it's burn. without getting all kinds of high tech here that is
what is basically going on.
chuck.
rusty italian metal is as depressing and as hard to weld as vintage spriget
metal.
cutting and-a-hacking my way to structural rigidity!
----- Original Message -----
From Bill Miller <millerb at netusa1.net>
To: <spridgets@autox.team.net>
Sent: Sunday, July 09, 2000 10:10 PM
Subject: WAS: Non LBC Motorcycle question. NOW: Fuel to Air Mixtures.
> Ok, forgive me for being dense, but explain this to me in detail!
Everyone
> who has answered has agreed that by increasing the exhaust gas flow, I
have
> decreased the fuel/air mixture (made it lean)
>
> Here's my problems with that theory:
> 1) This is a four stroke engine. Exhaust "cycle" and intake "cycle" are
> mutually exclusive. Exhaust valve open, exhaust gases leave. Intake
Valve
> opens, in comes the fuel/air mixture. So what does it matter that the
> exhaust leaves fast or slow (as far as mixture is concerned)?? Granted it
> is less work to push the exhaust gases out the valve, but again, how can
> this affect mixture???
>
> 2) For sake of argument, lets say it does matter. Intake air is going in
> "faster." Ok, this is a 750 cc motor. Each cylinder holds 187.5 cc of a
> fuel/air mixture. I am not increasing volume. I am simply increasing
rate.
> still X amount of air, still Y amount of fuel. Y hasn't changed. All
I've
> increased is how fast it is going in, not compressing it or anything.
> Again, how did I affect mixture???
>
> See this started out about motorcycles, but has evolved into engine
theory!!
> Help me understand what you guys mean!
>
> Bill
>
> -----Original Message-----
> From: owner-spridgets@autox.team.net
> [mailto:owner-spridgets@autox.team.net]On Behalf Of Rick Fisk
> Sent: Sunday, July 09, 2000 9:22 AM
> To: William M. Gilroy
> Cc: WFO Herb; Bill Miller; fooshst; George Procyshyn;
> spridgets@autox.team.net
> Subject: Re: Non LBC Motorcycle question.
>
>
> Bigger jets to get the air/fuel ratio back where it belongs = more power -
> arr,
> arr <g>
>
> Rick
>
> "William M. Gilroy" wrote:
>
> > WFO Herb wrote:
> > >
> > > By reducing back pressure, exhaust gases flow freer allowing for
intake
> to
> > > fill the cylinder quicker yet without increased fuel flow... a.k.a.
> amount.
> > >
> >
> > So would the a solution to this be re-jetting the carbs, and if so would
> that
> > keep the HP increase? Or if done correctly could you wring a bit more
> > power out of the bike by using bigger jets or is a lean burn required?
> >
> > Bill Gilroy
>
>
>
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