I just got home from college in florida (to pa)and went to start my '04 Ninja 250. My dad was starting it for me once a week while I was gone but he had to move for work so it was in the garage for about 2 weeks before I got home to start it. I rode it 3 weeks earlier and it was fine. But now when I start it it sounds like there is metal in it that is getting moved around. It was really bad at first time but not as loud or frequent now. I started it up again today and the noise was still there but i was listening for it. it wasn't as blatant as it was before. I changed my oil the last time I was up so idk what else it could be. any suggestions are welcome. thanks