Ed,
I have seen this several times on modern street engines and every time it has been the belt made improperly and a different brand belt fixed the problem. I know in your case you are stuck with Jesel for the belt but I think at the very least I would ask them to send you another belt and see if the teeth are made correctly. I sure as heck would not want to run it if the belt does not properly match the sprocket.
Just my opinion
