Just letting you guys know, magnets can go bad

[Guest]

I'm on my second stator. one From ebay the other from a respected forum member. Still not putting out enough ac voltage. Any know a good source for magnet assembly?

[Steve]

Can you give us a clue ... WHAT BIKE???

.

[tkent02]

And how many poles?

[Gorminrider]

"Do Magnets Ever Lose Their Magnetism?"

http://www.physlink.com/education/askexperts/ae472.cfm

and from

http://www.magnetsales.com/design/faqs_frames/FAQs_2.htm

How permanent is a magnet's strength? If a magnet is stored away from power lines, other magnets, high temperatures, and other factors that adversely affect the magnet, it will retain its magnetism essentially forever.

Will magnets lose their power over time?
Modern magnet materials do lose a very small fraction of their magnetism over time. For Samarium Cobalt materials, for example, this has been shown to be less that 1% over a period of ten years.

[shovelhead]

A 81 gs850 . We've been all over the wiring, two regulators, two stators, I've read the info that was just posted. That why we bought the second stator. At least now we have spares.

[tkent02]

If you stick something made of steel onto the magnet does it fall off?

[shovelhead]

Yep , they still held a piece of steel pretty good. That's why we got the second stator. Because we figured magnets physically worked so had to be stator. Not sure the poles because first one got thrown out but in each case I purchased a stator for an 81 gs850

[shovelhead]

So I guess I could change the title of the thread because the magnets still work , it just not working properly.

[JEEPRUSTY]

Wasnt there a thread on this very subject a few weeks ago
something about a mid year change in numbers of stator poles etc.

[shovelhead]

I'm on my phone and search option doesn't work properly. I'll search it when I get home.

[Steve]

Wasnt there a thread on this very subject a few weeks ago
something about a mid year change in numbers of stator poles etc.

Not sure if it was "mid-year" or not, but most, if not all, of the '79 and older bikes had 12-pole stators, the '80 and newer bikes had 18-pole stators.

Normally, the '81 in question would take an 18, but who knows what one of the previous owners might have done.

Shovelhead, if you have the stator cover off, take a screwdriver (or some other metal piece, if you don't want your screwdriver magnetized) and run it around the inside of the rotor, counting how many times it is attracted. It will jump from one spot to another as you go around, just count the number of times it is pulled to the rotor.

.

[tom203]

The correct rotor for 18 pole stator has 6 pairs of N /S magnets, The one for 12 pole stator has 4 pairs of N/S magnets. You can use a plain old refrig magnet (one side is N other is S ) to move it around inside of rotor- it will " grab" six times and " repel" six times on the rotor for the 18 pole ststor.

[OldVet66]

Not sure if it was "mid-year" or not, but most, if not all, of the '79 and older bikes had 12-pole stators, the '80 and newer bikes had 18-pole stators.



.

The '78 and '79 GS1000 had 18 pole rotors, not sure about other models..

[shovelhead]

I'll try these tests. That very well could be the problem.

[shovelhead]

I guess since it's a electrical part that exchange is it if the question. if the rotors are interchangeable it would make sense to get one that matches the two good stator that we already have.