10 cent charging diagnosis please...

Curious. Anybody here ever punch one of these apart, with pics?
I took mine apart and reused the winding from the one I bought, since they were on a plastic bobbin. I had to machine the oem halves a little to make it fit properly, but it pressed apart and together with about 2 tons of force, which isn't that much for a press fit. Sadly, the windings packed it in on the first trip. There was no epoxy on the rm stator windings, so I am wondering if they moved around with the vibes and rotation and chafed through the insulation.
 
Great rotor pic, Jim.

Ok, lemme share this concept, plant a seed (or lay an egg).

Take some small rare-earth magnets.
MagnetsTiny.jpg

And bury some in strategic locations in the rotor parts.
MagnetsRotor.jpg

Maybe in the inner rings?
Maybe in the arms?
Maybe in the fingers?

The idea would be to have a semi-PMA, or boosted-PMA, that would be able to put out just a marginal or minimum amout of power when the rotor coil is unpowered. A crippled, limp-home capability.

Of course, the magnet orientations would be critical, since the 2 different alternator setups have the current running in opposite directions, opposite polarities, making a rotor a dedicated 70-79 type or 80-83 type.

It could help during starting.
Reduced rotor current during operation.
Rotor coil or regulator fail, unplug regulator, limp home.
Just enuff output to handle minimums, without overcharging.

I can switch lighting on/off on my XS1B, to manage overcharging. And, bikes down here don't require running lights on models older than 1975. So, my needs would be down around the 2 amp range.

Different challenge for later bikes.

A viable project?
 
if ever my plane crash lands somewhere in the desert and all I've got is a box of matches , a couple of shotgun shells and some gaffa tape,..... please god 2M is also in the plane ......:)
 
Great rotor pic, Jim.

Ok, lemme share this concept, plant a seed (or lay an egg).

Take some small rare-earth magnets.
View attachment 117439

And bury some in strategic locations in the rotor parts.
View attachment 117440

Maybe in the inner rings?
Maybe in the arms?
Maybe in the fingers?

The idea would be to have a semi-PMA, or boosted-PMA, that would be able to put out just a marginal or minimum amout of power when the rotor coil is unpowered. A crippled, limp-home capability.

Of course, the magnet orientations would be critical, since the 2 different alternator setups have the current running in opposite directions, opposite polarities, making a rotor a dedicated 70-79 type or 80-83 type.

It could help during starting.
Reduced rotor current during operation.
Rotor coil or regulator fail, unplug regulator, limp home.
Just enuff output to handle minimums, without overcharging.

I can switch lighting on/off on my XS1B, to manage overcharging. And, bikes down here don't require running lights on models older than 1975. So, my needs would be down around the 2 amp range.

Different challenge for later bikes.

A viable project?


"A viable project?"


You mean like these.... :rolleyes:

IMG_20180426_102000.jpg


I bought these magnets last yr. After a little ponderin'..... decided the holes might weaken the castings too much. I'm gonna do some more math before I order some more smaller ones. It's on the back burner right now 'till I get the SG done

But to answer your question.... yeah, I think a "limp home" rotor is entirely doable.
 
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Next, how do you balance the thing...?
Well, dynamic balancing is beyond the scope of my tooling. Figure I'll make a cone fixture and do a knife edge static balance. As bad as an XS vibrates.... should be good enough.
 
I had considered rewinding my rotor but lacked a press for dismantling and reassembling. Also the cost of wire and epoxy was going to make it hard for me to do better than a rewound rotor for 108 Pounds. I found the following video on Youtube that shows how to do the rewinding:
Very informative I thought.
 
Hi Paul,
I've seen that video. It is pretty informative. Wire's pretty cheap on Amazon... and I've got the size and number of turns from a pro.

I was thinkin' about using clear JB Weld for epoxy. Anybody have any thought on that?
 
When I see other videos they seem to dip the rotor winding in epoxy. Is this to have the epoxy penetrate the fibre-glass ribbon and turn the windings into a solid mass for rigidity and better insulation? The araldite two pack epoxies are very thick, but from my sailing days the marine epoxy formulations were very thin, perhaps these would be a better choice?
 
I like JB-weld, use it on just about everything.
Might want to double-check thermal and dielectric properties.
Doing it in a vacuum chamber would eliminate voids.

How is the coil fitted and locked to the rotor innards?
Not allowed to rattle in there...
 
I'm wondering if a small Suzuki alternator from a Katana or Bandit would fit where the starter motor is. Maybe send a shaft through the case and have the starter gear permanently engaged to drive it.
 
New Rick's Motorsport rotor is on the way. It was advertised as being for a 75 to 81, but I looked at it and it has the magnet. Is there any reason this will not work on my 83?
 
According to Rick's website the '75 - '81, and the '83 all use the same Rick's part number 41-400. I think you're OK.

Rick's epoxy and assembly has a great reputation. They had some trouble with their epoxy in the beginning, but they have that beat now.

Scott
 
Yes, as long as it has the pick-up magnet, it will work on any '80 and newer electronic ignition model, those rotors were all the same. In fact, it would work on any 650. The earlier points models just wouldn't utilize the magnet.
 
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