This may be a real newbie question but I'll give it a go.
I'm learning more about the oil system of the Type IV but I feel unclear about the need/implementation of oil breather systems. Are the systems designed to relieve excess pressure from the crankcase? When are oil breather systems needed (on every engine or only engines that undergo certain levels of stress?) If I'm converting to carbs, will I need to fabricate an oil breather system? What are the pros and cons of the various systems (bottles, boxes, straight to the air filters, etc.)
I hope that made sense..