I have a Kawasaki zzr600 2006 with 14400 miles on it. I started hearing some engine clattering at higher rpms. Im assuming that it might need a valve adjustment now. My question is, is this a diffcult job to do. Im pretty good when it comes to fixing bikes but this will be my biggest job yet. Does anyone have any suggestions? Plus the dealership wants $500 for the job and i hate taking my bike in if i can do the job myself. Also i was in a pretty bad accident with the bike two months ago, i got hit from the back by a taxi cab but all it did was bend my subframe and some cosmectic damage. But can this hit cause this engine sound, and the sound only started about 2 weeks ago. Thanks for your help guys.