NHTSA owner reports · September 18, 2026 snapshot.
What owners actually said
34 reportsMileage unknown · Feb 10, 2023
Power TrainUnknown Or OtherVehicle Speed Control
Front drive shaft, chain sprocket ‘Nut/lock washer’ has came loose and fell off on the highway. Could have locked the chain around the wheel and cause a major crash, also could have severely damaged the engine casing. It damaged the rear swing arm and a piece piece near the stater. I replaced the nut & locking washer tab, exact …
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Front drive shaft, chain sprocket ‘Nut/lock washer’ has came loose and fell off on the highway. Could have locked the chain around the wheel and cause a major crash, also could have severely damaged the engine casing. It damaged the rear swing arm and a piece piece near the stater. I replaced the nut & locking washer tab, exact replacement only To have the same issue just I didn’t allow it to spin off since I was aware of this happening. I replaced the second one with a different style but same locking washer tab same issue it comes loose within 8 to 10miles. The nut is torqued to spec as stated by Yamaha. Iv reached out to several places including Yamaha and cannot seem to find a solution. Iv joined motorcycle forums and read people with same issue I’m having and wow am I lucky one. But they have had replacement parts and labor performed because of a safety recall of the issue. Why can I not get this resolved I have no clue what els to do.!! Please help
NHTSA ODI #11506635
3,000 miles · Oct 1, 2006
Electrical SystemCrashInjury
YAMAHA 2004 FZ6 BIKE RUNS GOOD FOR A WHILE, AND ALL THE SUDDEN THE ENGINE LOSES 90 % OF ITS POWER, I HAVE TO TURN THE KEY OFF, THEN BACK ON TO REGAIN POWER WHILE IN TRAFFIC, ONE TIME THIS HAPPEN I GAVE IT TO MUCH GAS TO GET OUT OF TRAFFIC ,AND I FLIPPED THE BIKE OVER IN THE MIDDLE OF THE STREET. IT WAS MY LUCKY DAY NOBODY RAN O…
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YAMAHA 2004 FZ6 BIKE RUNS GOOD FOR A WHILE, AND ALL THE SUDDEN THE ENGINE LOSES 90 % OF ITS POWER, I HAVE TO TURN THE KEY OFF, THEN BACK ON TO REGAIN POWER WHILE IN TRAFFIC, ONE TIME THIS HAPPEN I GAVE IT TO MUCH GAS TO GET OUT OF TRAFFIC ,AND I FLIPPED THE BIKE OVER IN THE MIDDLE OF THE STREET. IT WAS MY LUCKY DAY NOBODY RAN OVER ME. LOOKING AT THIS WEB SITE , THERE IS A LOT OF OTHER FZ6 RIDERS WITH THE SAME PROBLEM, I HAVE ASKED 4 YAMAHA DEALERS IF ANYONE ELSE IS HAVING THIS PROBLEM AND THEY ALL SAID NO? WELL THEY SURE DO BY LOOKING ON THIS WEB,I HAVE THE EXACT SAME PROBLEMS AS THOUGH OTHERS ON THIS SITE, AND A FACTORY RECALL IS NEEDED! SOMEONE GOING TO DIE IF NOT ALREADY THAT WE KNOW OF BECAUSE OF THIS PROBLEM. *NM
NHTSA ODI #10169691
300 miles · Jul 5, 2006
Engine And Engine Cooling
MOTORCYCLE SHUTS OFF AFTER REDUCING THROTTLE DURING DECELERATION AND DURING SHIFTING. MANY RIDERS OF THE SAME MODEL MOTORCYCLE HAVE REPORTED THE SAME PROBLEM. THIS IS DANGEROUS BECAUSE THE BIKE IS W/O POWER AND SOMETIMES DURING DOWNSHIFTING THE REAR TIRE LOSES TRACTION AND CAUSES THE BIKE TO SLIDE SIDEWAYS. *NM
NHTSA ODI #10161468
8,000 miles · Jun 13, 2006
Vehicle Speed Control
(1) NO UNUSUAL EVENTS. (2) THROTTLE POSITION SENSOR FAILED CAUSING POOR GAS MILEAGE, STALLS, AND HESITATION. (3) REPLACED TPS AT A COST OF $215. *NM
NHTSA ODI #10159712
12,800 miles · May 16, 2006
Electrical SystemCrashInjury
AT 9M MILES, MY 2004 YAMAHA FZ6 BEGAN TO EXHIBIT THE FOLLOWING: 1) AFTER APPROXIMATELY 30 MINUTES OF OPERATION, ERRATIC AND PROLONGED PERIODS OF ROUGH IDLE AT 500 RPMS INSTEAD OF THE NORMAL 1300 RPMS 2) MOTOR WOULD STALL DURING GEAR CHANGES, EVEN AT HIGHWAY SPEEDS 3) DURING THESE TIMES, THE SMELL OF GASOLINE WAS NOTICEABLE. …
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AT 9M MILES, MY 2004 YAMAHA FZ6 BEGAN TO EXHIBIT THE FOLLOWING: 1) AFTER APPROXIMATELY 30 MINUTES OF OPERATION, ERRATIC AND PROLONGED PERIODS OF ROUGH IDLE AT 500 RPMS INSTEAD OF THE NORMAL 1300 RPMS 2) MOTOR WOULD STALL DURING GEAR CHANGES, EVEN AT HIGHWAY SPEEDS 3) DURING THESE TIMES, THE SMELL OF GASOLINE WAS NOTICEABLE. CHANGING THE SPARK PLUGS SEEMED TO FIX THE PROBLEM TEMPORARILY, BUT THEY SOON REAPPEARED. AT 12M MILES, THE BIKE WAS TAKEN TO THE YAMAHA DEALER TO BE FIXED BUT THEY COULD FIND NOTHING WRONG WITH IT. I WENT NEXT TO AN INDEPENDENT MOTORCYCLE MECHANIC WHO ALSO COULD FIND NOTHING WRONG. HE SUGGESTED THAT IT WAS PROBABLY AN ELECTRICAL PROBLEM AND COULD BE EXPENSIVE TO FIX AND I SHOULD TAKE IT TO A DIFFERENT DEALER. HE ALSO QUESTIONED IF THE "CHECK-ENGINE" LIGHT HAD COME ON WHICH WOULD HAVE REGISTERED SPECIFIC TROUBLE CODES, BUT I TOLD HIM THAT THEY HAD NOT. AT 12800 MILES, WHILE PULLING ONTO THE ROADWAY, THE BIKE STALLED UNEXPECTEDLY IN A TURN AT LOW SPEED, LOCKED THE BACK TIRE AND WENT DOWN. I SUSTAINED MINOR INJURIES, AND THE BIKE LOST A MIRROR, FOOT PEG, FRONT FAIRING, AND GENERALLY GOT BUMMED UP. SINCE THEN, I HAVE FOUND NUMEROUS REPORTS OF "THROTTLE POSITIONING SENSOR" DEFECTS THAT HAVE CREATED SIMILAR PROBLEMS WITH THIS MAKE AND MODEL OF MOTORCYCLE. AND YET, THE DEALERS SEEM TO KNOW NOTHING ABOUT IT! INSTALLING A NEW TPS MAY OR MAY NOT FIX THE PROBLEM. BUT FOR NOW I'M STUCK WITH A BIKE THAT I CAN'T TRUST, HAS LITTLE RESALE OR TRADE-IN VALUE, AND PROBABLY ISN'T SAFE TO RIDE. AFTER READING THE NUMEROUS AND SIMILAR SOUNDING COMPLAINTS, THIS MAY WELL BE A MANUFACTURING DEFECT THAT SHOULD RESULT IN A RECALL. *NM
NHTSA ODI #10157688
19,840 miles · Mar 27, 2006
Fuel System, Other
VEHICLE: 2004 YAMAHA FZ6 MOTORCYCLE, PURCHASE NEW 12/93. INTERMITTENTLY, THE ENGINE SURGES, CUTS OUT, LUGS, STALLS/QUITS AT VARYING TIMES AND SPEEDS/RIDING SITUATIONS. STOPPING THE BIKE, TURNING IGNITION OFF AND ON TEMPORARILY CORRECTS PROBLEM, BUT PROBLEM ALWAYS RECURS. DIFFERENT WEATHER TEMPERATURES AND FUEL GRADES HAVE NO…
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VEHICLE: 2004 YAMAHA FZ6 MOTORCYCLE, PURCHASE NEW 12/93. INTERMITTENTLY, THE ENGINE SURGES, CUTS OUT, LUGS, STALLS/QUITS AT VARYING TIMES AND SPEEDS/RIDING SITUATIONS. STOPPING THE BIKE, TURNING IGNITION OFF AND ON TEMPORARILY CORRECTS PROBLEM, BUT PROBLEM ALWAYS RECURS. DIFFERENT WEATHER TEMPERATURES AND FUEL GRADES HAVE NO POSITIVE EFFECT. BIKE MAY STALL AT AN INTERSECTION STOP, AT HIGHWAY SPEED, ACCELERATING OR DECELERATING, ON STRAIGHT OR CORNERS, WHICH CAN BE TERRIFYING--NOT TO MENTION POTENTIALLY FATAL. NOTE: DATE LISTED BELOW IS ONLY THE MOST RECENT--PROBLEM OCCURS ON ALMOST EVERY RIDE. *JB
NHTSA ODI #10153851
8,000 miles · Mar 27, 2006
Electrical SystemCrashInjury
THIS COMPLAINT IS IN REGARDS TO THE 2004 YAMAHA FZ6 THROTTLE POSITION SENSOR. AFTER THE MOTORCYCLE WARMS UP (APPROXIMATELY 50 MILES OF RIDING), IT WILL STALL OUT AND/OR SPUTTER WHEN THE CLUTCH IS ENGAGED AND/OR SHIFTED INTO NEUTRAL. LAST JULY IT STALLED OUT IN THE MIDDLE OF A RIGHT HAND TURN AROUND A RED LIGHT, RESULTING IN TH…
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THIS COMPLAINT IS IN REGARDS TO THE 2004 YAMAHA FZ6 THROTTLE POSITION SENSOR. AFTER THE MOTORCYCLE WARMS UP (APPROXIMATELY 50 MILES OF RIDING), IT WILL STALL OUT AND/OR SPUTTER WHEN THE CLUTCH IS ENGAGED AND/OR SHIFTED INTO NEUTRAL. LAST JULY IT STALLED OUT IN THE MIDDLE OF A RIGHT HAND TURN AROUND A RED LIGHT, RESULTING IN THE BACK TIRE LOOSING TRACTION AND CAUSING A CRASH. I WAS MINIMALLY INJURED, BUT THE BIKE SUFFERED SOME EXTERIOR DAMAGE. AFTER SOME RESEARCH I HAVE FOUND THAT THERE IS A PROBLEM WITH THE THROTTLE POSITION SENSOR. THIS PART WAS FIXED UNDER WARRANTY, BUT SEEMS TO BE AN ISSUE WITH MOST OWNERS OF THE 2004-05 FZ6.*JB
NHTSA ODI #10153797
14,000 miles · Feb 7, 2006
Vehicle Speed Control
THE MOTORCYCLE HAD PROGRESSIVELY WORSE STALLING AT STOP-LIGHTS AND STOP SIGNS. AT TIMES THE MOTORCYCLE WOULD STUTTER AND STALL WHEN TRYING TO INITIATE THE THROTTLE FROM A STOP, AND AT OTHER TIMES THE MOTORCYCLE WOULD RANDOMLY INCREASE SPEED WHILE CRUISING ON THE HIGHWAY. THE THROTTLE BECAME QUITE VARIOUS TO THE POINT IT WAS NO…
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THE MOTORCYCLE HAD PROGRESSIVELY WORSE STALLING AT STOP-LIGHTS AND STOP SIGNS. AT TIMES THE MOTORCYCLE WOULD STUTTER AND STALL WHEN TRYING TO INITIATE THE THROTTLE FROM A STOP, AND AT OTHER TIMES THE MOTORCYCLE WOULD RANDOMLY INCREASE SPEED WHILE CRUISING ON THE HIGHWAY. THE THROTTLE BECAME QUITE VARIOUS TO THE POINT IT WAS NOT SAFE TO RIDE IN TRAFFIC DUE TO NOT KNOWING HOW THE MOTORCYCLE WOULD REACT TO DIFFERENT THROTTLE INPUTS. IN ORDER TO FIX THE PROBLEM THE THROTTLE POSITION SENSOR HAD TO BE REPLACED. *NM
NHTSA ODI #10149681
4,834 miles · Jan 9, 2006
Fuel System, GasolineCrashInjury
MOTORCYCLE'S IDLE RPMS CHANGE ABRUPTLY, TO THE POINT OF STALLING WHEN AT SLOW SPEEDS. THIS ABRUPT CHANGE WAS THE SOURCE OF A REAR END COLLISION. THE BIKE HAD BEEN TAKEN IN PREVIOUSLY TO THE DEALERSHIP ON MULTIPLE OCCASIONS BUT NO CORRECTIVE MEASURES WHERE TAKEN, AS THE PROBLEM COULD NOT BE REPRODUCED. THE SYMPTOMS CORRELATE WITH…
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MOTORCYCLE'S IDLE RPMS CHANGE ABRUPTLY, TO THE POINT OF STALLING WHEN AT SLOW SPEEDS. THIS ABRUPT CHANGE WAS THE SOURCE OF A REAR END COLLISION. THE BIKE HAD BEEN TAKEN IN PREVIOUSLY TO THE DEALERSHIP ON MULTIPLE OCCASIONS BUT NO CORRECTIVE MEASURES WHERE TAKEN, AS THE PROBLEM COULD NOT BE REPRODUCED. THE SYMPTOMS CORRELATE WITH THOSE OF OTHER FZ6 USERS AND HAS BEEN LINKED TO A FAULTY TPS. *NM
NHTSA ODI #10147316
6,500 miles · Sep 24, 2005
Electrical System
MOTORCYCLE RANDOMLY WILL NOT IDLE AND STALLS BETWEEN SHIFTS. HAS HAPPENED 5 OR 6 TIMES. DEALER SAYS DESCRIBED SYMPTOMS CANNOT NOT BE DIAGNOSED WITHOUT FAULT CODES. FAULT CODES ARE NOT STORED UNLESS CERTAIN "IDIOTIC LIGHTS" COME ON DURING FAILURE. *NM
NHTSA ODI #10137517