I have a 1996 CBR900RR. On the way home it started rattling. The rattling noise was not that loud at first and would not rattle when reving. By the time i got home it was rattling a whole lot louder and it would rattle when reving. I did not hear any rattling when it was idle. When i went to the check the oil i needed to add some oil. I had to add 1 quart to make it show in the oil window. The bike has about 18k miles. Ever since i bought the bike its always made a low rattling noise when it was cold. After getting warmed up the bike would stop rattling. Im going to inspect it some more tomorrow morning. Does anyone know what this could possibly be. I dont want to take it to a local shop because they charge way to much. I seen the threads on the cct but not sure what thats supposed to sound like. Does anyone know?

 

It also lost power. It had power when it first started but after riding it and getting closer home it started losing power.

 

It could be many things. If your giving it throttle and it's rattling it be your cluth or little gears in your clutch. Also, if it's rattling when it's cold it could be timing chain...You should really keep oil in your engine. You don't want to break anything internal.

 

I'm thinking faulty cam chain tensioner causing slack in the cam chain (noise)
This could cause the cams to loose time, you would experience lose of power.