Brian gave you good advice..
Also Where Does the Clutch start to grab when you leave it out in first gear.. Using the handle bar as "0" .. If your answer is Right away,,,, IT is the problem you are looking for.. New(used) Bike to ME would mean All oil and filter changed.. Clutch adjustment along with the clutch cable adjusted properly...
I would Use Formal+ in the "primary-clutch-tranny" (one Hole) and a good Full synthetic 20/50 in the engine (other Hole).. Make sure it is the RIGHT oil filter for that Sporty.... A TC filter will damage the engine if used by Mistake..
signed....BUBBIE