When my mechanic rode the ZZR recently to check out the caliper modification he came back and said the brakes were great but he noticed that the head bearings were worn. Now I had done the check of the bearings by moving the handlebars from side to side and they seemed fine. I also checked the front to rear movement of the forks. Again I thought they were fine. Anyway, because I really trust this guy I ordered some new bearings and they were fitted today. What can I say, the bike felt totally different after they were fitted. So easy to turn in and just a whole different feel. He also noted that the gear change lever felt a bit stiff.Again, not something I noticed. Anyway, he stripped it and greased everything up. When you ride the bike nearly everyday you just dont notice these little faults developing. You just adapt.
I have just ordered new bearings for the front and rear wheels. The fronts are a little notchy so I will change the rears as well.