Evaluating a bike for purchase. One thing I noticed was a high pitch metallic "tinking" at idle. Anything to be concerned about? (I've been reading about cam chain tensioners.) Sounds similar to this: https://soundcloud.com/heath-taylor-4/2007-ninja-650r-odd-metallic
Also, should I get new tires immediately even if they have very low miles on them if they are 5-6 years old?