When I 1st rebuilt the carb I had glanced at the reed valve, and had thought it looked OK. But after taking the carburetor off again to double check everything I inspected the reeds more closely. Two of them were well seated against the housing with good pressure holding them in place, But, two of them were not fully seated, I could see a sliver of clearance between the valve and the housing. I guess this can explane how I could get a great ideal but could not advance the throttle at all without it Dieing.

The Carburetor is so simple I was sure I had rebuilt it properly, all the way down to checking the settings of the metering valve.

I have ordered replacement from Desert Aircraft.

Thanks to everyone who gave me suggestions.