Flyon speed sensor rotor

[AJR]

Just a heads up on what could happen to any owner. A few rides ago I had a small branch got caught in my rear wheel, no big deal. After removing it and riding on the power seemed a bit erratic. About 10 miles further on the display said I had a speed sensor issue and lowered the power supply. I switched off and back on and it worked but seemed to have some sort of issue. I plugged in the diagnostic tool and no error codes came up. The next ride was all ok until 21 miles and the same display. On close inspection the sensor rotor had a dent in it. Even after a bit of fettling it looked ok but still gave erratic signals to the motor. I put a new one on, and have done a 42 mile ride today without fault. So if you get any strange motor problems check this part first.

 

[Mikedodds]

Looking at mine it does seem quite exposed for a critical component - particularly with the fine tolerances the sensor has - as we have read about in other threads.

 

[arawa]

Happened to me as reported on another thread.
I could see nothing at all wrong with the sensor but my bike shop told me the brake disk itself had very slightly warped (no idea how in the middle of a ride on a track) and this had pushed the speed sensor disk out of tolerance.