2011 F800GS with 5500km has tach that shows ever increasing rpm's during a ride. I can get the needle back to zero by cycling the ignition switch on an off five or six times without starting the bike. Ride off again and ten minutes later the tach shows 7, 8, 9000rpm when it is really reving at 4 or 5000rpm. Any one seen this? have not had opportunity to take it to the dealer yet.