I actually found mine to be just the right length. Mine acted up and was sticking when I first put it on, turned out that it just needed to be oiled. I would try that before anything else as we thought mine was binding up. It was the metal part that goes into the throttle that needed the lubing and was binding up, after oiling it turns so easy now.
Your not alone with the tapping. Mine does it to, dont have a clue what it is, new timing chain, I know its not hitting the head, valves are adjusted perfect, just has a weird noise. I dont care anymore though, still runs perfectly.