Silencer repack 2003 yz450f??

[calgaryresq]

Just bought the bike this year. It is my first so I am learning as I go. A friend told me that I should think about repacking my silencer. Problem is, it is rivetted together. I have read some other post for different bikes which do not require repacking and am wondering if the same is true for mine. I beleive it is the stock pipe. Also, if it does not need to be repacked, is there other maintenance I should be doing?
Thanks