As I understand it, the idea is that the increased velocity of the
air through the venturi (due to the piston being held in position by
the damper / oil) increases the vacuum that is applied at the base of
the needle and which sucks more gas out of the jet tube, giving more
fuel for a given quantity of air. That's what enrichens the mixture.
Tony
At 10:41 AM 3/21/2012, Allen Hess wrote:
>On Mar 20, 2012, at 10:15 PM, triumphs-request at autox.team.net wrote:
>
> > oil weight is quite literally the acceleration enrichment control.
> > A thick oil will make it run richer by slowing the response of the
> > piston, increasing air velocity over the bridge drawing more fuel
> > a thinner oil will let the piston rise more rapidly, shortening the
> > enrichment time.
>
>I've no argument with the above but it always makes me ponder the
>following. Since a rising piston/needle also allows more fuel to flow
>due to a smaller needle diameter, I've always wondered about the
>seeming contradiction in above. Can someone elaborate a little more?
>
>Allen
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