[Honda-C70] Re: Air blowing out of carb, not sucking in

 

So when piston starts to rise for compression after intake down stroke is completed, for a fraction the intake valve keeps open.

So at slow rpm air in speed is slow and some bounces out during this fraction up piston movement, while fast air will keep going in due to its inertia although piston has risen a bit.

--- In Honda-C70@yahoogroups.com, william belleau <wjbelleau@...> wrote:
>
> Think about it!!!! The intake valve is open when the piston is coming up toward top dead center.
> When the engine is running the column of air is being sucked into the carb and into the cylinder.
> This is during the piston down stroke. Then as the piston starts up on compression, the intake valve is still open,
> it is starting to close. The mass of air in motion thru the carb and intake passage does not stop on a dime, it still flows
> into the cylinder completing the filling of the cylinder.
>  
> Turn the engine over slowly and the air mass is much less and the flow will turn around and flow out of the cylinder
> as the piston comes up on compression. That is when you feel the air flow out of the carb.
> Bill
> Portland OR
>
> From: Jill <jillvee@...>
> To: Honda-C70@yahoogroups.com
> Sent: Monday, August 1, 2011 9:01 AM
> Subject: [Honda-C70] Re: Air blowing out of carb, not sucking in
>
>
>  
> It should be sucking not pushing though right? Every motorcycle carb i've ever had sucks air in
>
> --- In Honda-C70@yahoogroups.com, Mindspring <mgladu@> wrote:
> >
> > A little air coming out of the carb is normal.
> >
> > Mike G.
> > -
> >
> > Sent from my iPhone
> >
> > On Aug 1, 2011, at 12:39 AM, "Jill" <jillvee@> wrote:
> >
> > > On my '83 Passport, I have air blowing out of my carb. That is
> > > usually valve issue's right? what can i do about this?
> > >
> > >
> >
>
>
>
>
> [Non-text portions of this message have been removed]
>

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