I have an XBR500 that starts and runs perfectly up to 6500 to 7000 revs,then cuts out.It feels electrical.I've done the obvious- carb,air filter,tappets,petrol tap,new plug etc. to no avail.Any suggestions??It's no big deal,since 6500 revs is normally plenty,but it annoys me because I can't find it.Coil???CDI???Sender unit???Any thoughts gratefully welcomed.