won't there be problems later on because of the 9000 rpm redline? and ragging out the engine will also cause more problems any suggestions on what to do?

also any good additives to add to the car such as oil and stuff so i can keep up the car top notch?

 

A similar question has just been asked here:
https://www.s2ki.com/forums/showthread.php?...threadid=108318
Other than what the owner's manual says, you should not feel that you need to do anything special. 9000 rpm is only "special" in cars because it has not been seen on a production, mass produced car. Motorcycles have been revving well over 10,000 rpm for decades and many of these, when taken care of properly has lasted up to high mileages.