NHTSA Complaint #10121061 — 2004 YAMAHA FZ6

2004 YAMAHA FZ6 5K+ MILES. WHEN CRUISING AND KEEPING THE ACCELERATOR CONSTANT, ONE EXPERIENCES SUDDEN CHANGES IN ENGINE-TO-TRANSMISSION POWER FEED: THE BIKE SUDDENLY STARTS TO ACCELERATE OR SLOW DOWN. ONE MUST COMPENSATE CONSTATNLY FOR THAT ERRATIC ENGINE BEHAVIOR, WHICH TAKES AWAY FROM PAYING ATTENTION TO THE ROAD. IF DOWNSHIFTING, UPSHIFTING OR CLUTCH DISENGAGEMENT IS PERFORMED DURING THE ENGINE FALTERING, THE RESULT IS A STALLED OUT ENGINE UNLESS SHIFTING IS PERFORMED VERY QUICKLY. STALLING OUT WHILE DOWNSHIFTING FOR A FULL STOP AT AN INTERSECTION GETS DICEY GIVEN THE AMOUNT OF OIL/WATER USUALLY FOUND AT STOP LINES AND THEIR APPROACHES. THIS PROBLEM TENDS TO APPEAR AFTER ABOUT 20-30 MINUTES OF ENGINE OPERATION AT ALL SPEEDS, TEMPERATURES OF ENGINE OPRATION. IT CLUTCH IS DISENGAGED, THE ENGINE IDELS DOWN TO 400-500 RMP (INSTEAD OF THE USUSAL 11-12K) AND INVARIABLY STALLS. STARTING THE BIKE RIGHT BACK DOES NOT ALLEVIATE THE SITUATION. THE ONLY REMEDY I WAS ABLE TO FIND WAS TO TURN THE IGNITION OF, TURN IT BACK ON (EVEN AFTER 2 SECONDS) AND START EH BIKE AGAIN. IDLING RMPS COME BACK TO NORMAL AND THE BIKE RIDES FINE AFTER THAT. TURNED BIKE INTO DEALERSHIP, REPORTING THE ABOVE SYMPTOMS ALONG WITH REPORTS OF THROTTLE POSITION SENSOR PROBLEMS REPORTED BY OTHER FZ6 RIDERS. DEALER COULD NOT REPLICATE THE PROBLEM AND SIMPLY REPLACED IOL/GAS FILTERS, AS WELL AS OIL. UPON RECEIVING THE BIKE BACK FROM THE DEALERSHIP, OF COURSE THE PROBLEM CAME BACK.