Rare earth magnet on points rotor

Yes Virginia, it can be done!
Having two good points rotors and one bad TCI rotor on hand I decided to try adding a rare earth magnet to one of the good points rotors and convert it to fire the TCI.

You need a TCI rotor to make a paper template for proper magnet placement.


Place a sheet of paper over the rotor, mark and cutout the threaded middle section so the template will sit flush on the rotor face.


Next place a 1/4"X1/16" rare earth magnet over the imbedded magnet. Trace around the magnet. Use the edge of a pencil and rub the outer edge of the rotor for boundarys sake. Rub the TDC mark on the rotor getting the timing mark.


Now remove the paper and carefully cut out the magnet location...exacto knife is good here. Trim around the outer boundary edge. Place the template on the points rotor lining up the timing mark on the paper template to the timing mark on the rotor.


You can see here where I trimmed the template a little at the timing mark so as to line the template timing mark to the rotor timing mark.


Mix up a little epoxy, I used JB Weld, and epoxy the magnet in its place. The magnet sits right on the outside edge of the outside slipring. This will keep the magnet out of the brush path and coincides with its placement on the stock TCI rotor. Let it set up good before using.


Does the polarity of the magnet matter? Not sure but I believe I transffered it directly from the bad rotor to the good, so the polarity would have been the same.

The rare earth magnets can be found on Amazon but you have to buy twenty to get one.

I have this installed on the '78 I picked up this past spring and it's working. Here you can see the magnet approaching the pickup at the top as the rotor timing mark approaches the timing tab on the stator.


In the process of putting this visual together I came across my original, very sophisticated template, slightly yellowed, as I did this experiment a few months ago but only got the bike truly running the other day.


Now to sort through these 38's and fix this low speed stumble.......dam mud dawbers.......

PICTURES!

Good on ya for blazin the trail! And double damn the daubers!!

I'll see if I can put something together visually ....such a pain using that old desktop, crappy camera, photobucket and this hand me down iPad....

Thanks WER!

Well laid out............ Visualized as i read it.

Tech menu.

yup get some pics up, I'll add a link to the charging guide!

Pics added.
Thinking about how off time it could be and I can only imagine a millimeter or so. The true test would be to have a comparison with a timing light - check a stock rotor and then swap it out and test the modded rotor on the same engine. If an adjustment absolutely had to be made then the pickup could be moved ala XSJohn and his lower compression mod.

Of course, this whole exercise is moot if you have money to spend for a new or rewound rotor, but truly fits the pocket of those that have the parts and a spouse that watches the pocketbook.....
Thanks fellas!

I added a link to this thread to the charging guide. (bottom of post #4) Thanks NJ

Thanks G, so glad to help.

Old thread but wondering on longevity of this mod? Has anyone else done it? Got a good used rotor will take a look at doing this or sometime just swap out the entire rotor, stator when fails and install advance mech to house pamco.

In summation of the project.
It worked but didn't work well.
I happened upon a stock TCI rotor and this got set to the side.

I went with using the face and timing marks of the TCI rotor to make the template for the magnets position on the points rotor, and in retrospect the crank key slot should have been the guide for the magnets positioning. I don't see why the timing marks would have been different to the cranks key slot and I never went the extra step to see if it was.

This would best be done on a known good runner with no other issues to second guess performance.
I still have the rotor and my '77 is a good runner so now I need initiative. lol

Good to know NJ. It is a good write up you had and I was also wondering about the epoxy for the magnet vs heat from the engine. There must be some that are high heat resistance. I will check keyways vs timing marks and magnet locations to see if any differences.