2004 Yamaha FZ6 Electrical system Problems

“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? …”

“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. …”

“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.”

“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. …”

“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. …”