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 at 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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