Hello, i am the owner og a 1981 Yamaha XV 750 SE, but now i have a huge problem.  The engine runs normaly up to 5000 rpm (exactly 5000).  Then it cuts and the counter goes back to 0 rpm befor the engien starts again and runs normaly up to 5000 rpm.  Sometimes it can be revd over 5000 rpm and then runs normaly up to top.
The problems occurs bout driving and no driving.  But i seems to be more present when driving with load (two people).
Any tips?  
Look foreweard to hear from you
Regards
Sture Nyhagen
Norway

I have heard similar stories, where the cause was a contact in the ignition switch or somewhere else, that openend and closed because of the vibrations of the engine. Sidestand switch or clutch switch and similar useless things often cause problems too.
Bye,
Georg