[barossi73]

Crankcase drain is seperate from transmission oil so doesnt matter if you have dropped trans oil or not.its useful for draining water when bike has drowned or in your case for eliminating coolant/excess oil fouling the fuel mix
Smoking from pipe after engine off can also occur after a prolonged wot run,esp if there was a lot of slow puttering before.the excess oil buildup gets hot enough to smoulder in pipe.could be,but not necessarily a lean symptom.