Fairly New Crystalyte TC-80 Hub lost power, making noise

[drutledge]

I have a fairly new (<250 miles) Crystalyte TC-80 which all of the sudden has lost power (but not 100% maybe 75%) and makes a sort of 'slipping' sound. Like a clutch not grabbing. When it first happened I thought that my bike tire was spinning out on gravel. The bike moved but not much and the sound made it seem like something was spinning but not grabbing. It sounds like the stator is spinning instead of the outside of the hub but that would be impossible, right?

I've made a video :
In the video it sounds more 'buzzy' than before. That might just be the bike vibrating. In the video we're applying maybe 25% throttle.
[youtube]http://youtu.be/ZzCRbsX4tGM[/youtube]
http://youtu.be/ZzCRbsX4tGM

Any ideas?

 

[amberwolf]

Sounds like a phase is not working right, or a hall is not connected/not working. Most likely issue is a bad connection somewhere.

 

[drutledge]

I've checked the external connections fairly well and everything seems fine. Could it be a controller problem? Tomorrow I'll hook up a different controller and see if there is a difference. If it's the same, I guess it's internal and hopefully something obvious.

 

[Brentis]

I would very closely examine the wiring coming out of the motor.
I would have thought Crystalyte fixed this, but my HS motor had a very sharp wiring exit path through the axle.
After about 2 or 3 km of rough road I developed a similar sound from my motor, but I lost most power, just enough to turn the motor not run with me aboard. The phase wires had been cut open at the axle exit and were shorting, creating that situation.
Hopefully the second controller solves it, but check those wires first so not to potentially damage the controller, as a phase shorting has that potential.

Edit

Not only was it sharp axle, but potentially the plastic shield rotating that cut my phase wires.

 

[drutledge]

I tried the second controller and it was the same. I also tried disconnecting the hall sensor wires going to the controller thinking that if there was a short with those, the problem would go away (controller can work sensorless) but the problem is still there. Next step is to take the motor apart I guess? I've looked for outside evidence of shorting but don't really see any. The outer sheath that holds all the wiring is frayed but it was that way when I bought the motor.

For what it's worth, the problem only occurs under load. If I take the rear wheel off the ground, you'd never know there was any problem.

Made a second video in which you get the sound of the 'spinning' better.

http://youtu.be/cBSPBCXjYB4

[youtube]http://youtu.be/cBSPBCXjYB4[/youtube]

 

[Brentis]

I tried the second controller and it was the same. I also tried disconnecting the hall sensor wires going to the controller thinking that if there was a short with those, the problem would go away (controller can work sensorless) but the problem is still there. Next step is to take the motor apart I guess? I've looked for outside evidence of shorting but don't really see any. The outer sheath that holds all the wiring is frayed but it was that way when I bought the motor.

For what it's worth, the problem only occurs under load. If I take the rear wheel off the ground, you'd never know there was any problem.

Made a second video in which you get the sound of the 'spinning' better.

http://youtu.be/cBSPBCXjYB4

[youtube]http://youtu.be/cBSPBCXjYB4[/youtube]

Mine was frayed/cut from new as well, and you could barely see the problem, I mean you really had to look.
Made very much the same sound.
Odd that it only makes that sound under load though, not sure what to make of that.
My money is on that frayed sheath, there will be a cut wire in there shorting out.

Best of luck.

 

[drutledge]

Ok. I took the wheel off and looked for signs of shorted wires but found nothing. Popped open the wire side cover and still found nothing but I did find something very interesting:

The magnets are not glued to the outer hub! They all move in and out with a fairly light push of a screwdriver. This is not correct, right? The 'spinning' sound that I've been hearing is, I'm pretty sure, the actual magnets spinning along with the rotor (edit: I guess spinning along with the magnetic field of the stator is more accurate. While the 'rotor', the outer hub, stays put) when the wheel is under load. When not under load I think they stay in place and the wheel spins normally as I noted before.

I should not be able to move the magnets right?
For what it's worth, I've closely monitored the temp of this motor since overheating of a smaller motor is why I bought it. It has never gone over 85 C even on the hardest of tasks. You can see in the photo the windings are still a nice pink.

The inside has an odd smell, like fresh spray paint; not an electrical smell, more chemical. There are little balls of what looks/feels like rubber cement at the sides of the magnets as well.
Picture of a magnet pushed in:

 

[Brentis]

Those magnet should definitely not move, they should be glued in place. This is your problem.
The magnets can be re glued, but some show damage in your pics. I'd check them all for integrity. You may also have had pieces of magnet flying around in the hub potentially damaging windings, look for that too.

You say it's fairly new motor. Where'd you purchase from? Any warranty?
I'd want a replacement.

 

[drutledge]

Yeah, I thought that wasn't right!

I think the magnets are actually ok but I wouldn't even want to attempt to reglue them. I'm sure they are all unglued since that's what it would take to get the slipping clutch sound that I hear. Maybe the new guy at the factory built this motor! I wasn't even pushing the motor when the magnets let go. I had my 80lb. mother-in-law in the front seat and was on a flat alleyway. (The bike is an antique Cambodian cyclo or front seat rickshaw)

I bought the motor this spring and only mounted it on the bike a few months ago. To my eye the windings look great and there's no evidence of overheating - and for what it's worth, I've had other motors literally smoking hot, windings turn black and not had the magnets physically let go. Clearly there's a manufacturing error here. I bought the motor from of a very reputable outfit, hopefully they will stand by it. It's not a cheap motor that's for sure. I will hold off naming them for now, I don't want to appear to be holding their good name hostage.

 

[Brentis]

Yeah, I thought that wasn't right!

I bought the motor this spring and only mounted it on the bike a few months ago. To my eye the windings look great and there's no evidence of overheating - and for what it's worth, I've had other motors literally smoking hot, windings turn black and not had the magnets physically let go. Clearly there's a manufacturing error here. I bought the motor from of a very reputable outfit, hopefully they will stand by it. It's not a cheap motor that's for sure. I will hold off naming them for now, I don't want to appear to be holding their good name hostage.

Nice etiquette. I wasn't suggesting naming them. Just hoping you had warranty because I'd call that manufacturing defect.
Hope they stand behind it.
The windings may appear fine, but where did those chunks of magnet go? Which path did they take? Damaged varnish on the winding can be very hard to see.
Anyways, hope they get it sorted for ya soon.

 

[drutledge]

The magnets are still whole. It's just that I can push them sideways since they are unglued. I have both covers loose so they have room to move. I put a light score where the magnets' edge meets the outer hub. If I tap on the axel and move the stator the magnets move with it and cover up/reveal more of the score. If I popped the whole stator out I'm sure all the magnets would come along for the ride!