pulling choke while running

[jabkwab]

Hi all,

What should a Rotax 912ul do when you pull the choke with the engine running?
Mine speeds up about 200RPM, except at wide open throttle.
Rough running only happens at the very end of the stroke (of the choke cable).

To me this seems to indicate a lean mixture, or am I seeing things?

Thanks, Jan

[Av8r3400]

The "choke" or enriching circuit only has any effect when the throttle plate is closed. When the throttle is open further than idle the ports will not do anything because there is no venturi effect if the lever is engaged.

I would suspect that pulling your enriching cable may be flexing the throttle cable or even the carb position slightly causing your increase in RPM.