So I bought that 92 ZX7 the other day. I took it out for my first real ride to Belcarra Park today. On the way back, going down Hastings, I started to notice a sporadic whining/wailing noise at aroud 6-7 thousand RPM's (think: "WAAAAAAAAA... WA-WAAAAAAAAA-WAAAAAA"). It occured mainly when I was semi-coasting/minimal throttle so maybe it has to do with compression braking... The sound is accompanied by a noticable vibration that I can feel through the tank and I noticed it most in 3rd gear. I haven't taken it out since to recheck for it.
If anyone has this or a similar bike and has any idea what the hell I'm talking about, let me know. It could be that this is a normal noise and I'm still getting used to the bike, but it doesn;t seem like a healthy sound to make!