I have been struggling with the rebuild of a WO carb on a M38. Was not bad but allways had a little something. Did not like choke at startup, weak accelerations, etc. Bought a $100 Solex, just for fun. Just to try.. Verdict.... Awsome! Fisrt try, Easy start, got warm, smooth running. I will be selling my WO on Ebay. Happy Camper now. Life is Good