Well, still no luck. Peaked both high and low and slowly starting richen the low to get some kind of transition with the same results as stated in post one. I noticed today, that really any position below about half throttle it will die if you quickly advance the throttle. If you slowly advance the throttle or cycle the throttle from full advance to idle without stopping it runs like a champ.

Set up:
BME 50
Stock Banjo style muffler
CH ignition and Rcexl ignition
NGK BPMR6 .023 gap
Stihl HP Ultra 40:1
3/32 fuel line
Fiji Gas 16 oz tank
felt clunk
Xoar 21X8


Things I have tried so far:
Two different carburetors.
Changed the carb adaptor gaskets.
Two different ignitions.
And tons of needle turning

Things I have not tried yet:
Re-plumbing the fuel system
Tearing down the lower case of the engine and sealing it back up. (I don't see any evidence of leaking around the engine)
Purchasing a WT 201b carb for it. I would think the WT 664A would work just as well.


Any more suggestions would be great....

Thanks