I have a 2010 Zero DS with the Agni 95R motor. I was having issues with a grinding/rubbing sound and eventually a burning smell (you can read a longer description of symptoms below) that resulted in sending the motor to Zero for them to check the brushes, as they suspected that was the problem. They inspected them and determined they were fine and shipped the motor back to me with the explanation that the "magnets were weak, the only option is a whole new motor" which makes no sense based on the symptoms I experienced.
I managed to remove half of the motor casing to inspect the armature myself. I inserted a shim between the magnets and the armature and moved it around the armature to check the distance. There was certainly a difference in the spacing towards one side. I imagine this means one of two things. The shaft is very slightly bent, such a minor amount that I could not determine it by measuring - or - the shims have shifted out of place and the armature is not level. The only other observation I noted was that the edge of some of blades on the armature were ground away. This was on both sides of the armature, on the same outer edge; not opposing edges as one would expect if the rotation of the armature was tilted and it was rubbing - very strange.
Before I bother to remove the armature and continue inspection I wanted to start a thread and ask some more experienced folks out there what their ideas may be on my problem. I have no experience working with these motors so this overhaul is a also an education for me. Below are pictures I took when I cracked open the motor case. Obviously the magnets, the commutator, and just about everything else needs cleaning, but I know the problem is much more complicated than that.
A section of an email I sent to Zero describing my experience, after hearing a grinding/rubbing sound for a couple days and thinking initially it was my rear brake pads as I had just replaced them:
'In the evening when I went to go home, I started the bike, sat down and rolled the throttle. The warning indicator flashed three times. This, according to the manual indicated something was wrong with the throttle connection or the throttle was "ON". I investigated what I could in my company parking garage, but ultimately after turning the bike on and off a few times, it lurched to life. I drove the bike slowly and stopped periodically to check the brush less motor as now my suspicion was something was wrong there. The bike seemed to function fine on the drive, but at the end the cooling fan was running higher than I had ever experienced and something smelled burnt. I had also read in the manual that if the warning light flashes while driving it could mean the brush less motor is overheating and that I should pull over. I never got an such warning/flashing on the ride yesterday evening."
dirty communtator
View attachment 2
some black gunk against the side of the case
the ground away edge of the blades described above
another angle of the ground blades
Thanks in advance everyone.
I managed to remove half of the motor casing to inspect the armature myself. I inserted a shim between the magnets and the armature and moved it around the armature to check the distance. There was certainly a difference in the spacing towards one side. I imagine this means one of two things. The shaft is very slightly bent, such a minor amount that I could not determine it by measuring - or - the shims have shifted out of place and the armature is not level. The only other observation I noted was that the edge of some of blades on the armature were ground away. This was on both sides of the armature, on the same outer edge; not opposing edges as one would expect if the rotation of the armature was tilted and it was rubbing - very strange.
Before I bother to remove the armature and continue inspection I wanted to start a thread and ask some more experienced folks out there what their ideas may be on my problem. I have no experience working with these motors so this overhaul is a also an education for me. Below are pictures I took when I cracked open the motor case. Obviously the magnets, the commutator, and just about everything else needs cleaning, but I know the problem is much more complicated than that.
A section of an email I sent to Zero describing my experience, after hearing a grinding/rubbing sound for a couple days and thinking initially it was my rear brake pads as I had just replaced them:
'In the evening when I went to go home, I started the bike, sat down and rolled the throttle. The warning indicator flashed three times. This, according to the manual indicated something was wrong with the throttle connection or the throttle was "ON". I investigated what I could in my company parking garage, but ultimately after turning the bike on and off a few times, it lurched to life. I drove the bike slowly and stopped periodically to check the brush less motor as now my suspicion was something was wrong there. The bike seemed to function fine on the drive, but at the end the cooling fan was running higher than I had ever experienced and something smelled burnt. I had also read in the manual that if the warning light flashes while driving it could mean the brush less motor is overheating and that I should pull over. I never got an such warning/flashing on the ride yesterday evening."
dirty communtator
View attachment 2
some black gunk against the side of the case
the ground away edge of the blades described above
another angle of the ground blades
Thanks in advance everyone.