The stock cam is not balanced. Well, maybe you could static balance it but you couldn't dynamic balance it without welding on counter weights.
There is really no need to balance a camshaft, especially on a non-counterbalanced parallel twin. The cam lobes don't have much mass and that small mass is close to the center of rotation. Plus, the cam spins at half the speed of the crankshaft. Any vibration it presents is a drop in the bucket compared to the vibration from the crankshaft and reciprocating assembly.