Those years I believe have the quick release fittings on the sides that cover the tank and are known to become unhinged and catch air. The EWS ring around the ignition key slot, sub-harness can breakdown. Servo brakes can be more difficult to do fluid flushes on. If you found a bike that has gone to South America, check suspension and final drive play. Others are bound to chime in.
2008 BMW GSA
2000 Kawasaki Super Sherpa