Ken,

I haven't tried it yet, but am going to try a Walbro WA127A. It is a 2 needle model with a 9.53mm venturi (24 cast in the carb opening). This is not made for 4 strokes so I will tap the carb for an external pulse for the pump and hook that up to the crankcase breather tube through a "T" fitting. This will give the + and - pulses needed for this type of carb. The original carb on this engine is nonadjustable and has a 9mm venturi. I doubt that the WA127 carb is still in production, but I'm sure there are other Walbro and/or Zama carbs with the right venturi size and adjustability etc. I bought a box of carbs off the famous _ -_ _ _ auction site that were new "old stock" for just a few dollars each. Check the auction sites and auction site stores for Walbro carbs to find a good deal then look up the carb number on the Walbro site to see if it might be what you need.

Some guys who are running these engines on gas with magneto ignition are using the stock carburetor with some success.

Gary