Opinions on Aftermarket Magnetos Sought

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Re: Opinions on Aftermarket Magnetos Sought

Postby jOe » Sat Mar 23, 2019 5:31 pm

The FM in question came back and seemed very good. It started the bike on the first kick. Over the course of the next couple of weeks, it worked nominally, but then degraded quickly to the non- startable mode. On the bench, it does produce a spark driven by a drill, but not by hand. Can the magnetic charge go away that quickly, and if so, what’s the cause? The coil could also be questionable.
A rotor and coil costs almost half of what a new Morris M does, so it doesn’t seem to make a lot of sense to re-rebuild the FM.
Maybe stripping the parts out of the FM and making a desk lamp out of it would be a good afternoon project.
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Re: Opinions on Aftermarket Magnetos Sought

Postby Ferrous_Head » Sat Mar 23, 2019 6:43 pm

Yes, unfortunately when something like this lets us down we tend to get frustrated and annoyed to the point we want to throw said part into thee nearest river for a flotation test.
While I like your idea for a desk lamp ........
Seems you do have some parts worth salvaging.
You could ask Dave Shaw if his rotors fir into the FM bodies. If they do a quote for him to do the necessary work might help. If you can get the spark and reliability with the looks and patina of an original FM that might be worth considering.
Just now thinking I may do that myself. I have a "rebuilt" FM on my 66 CH that now only starts with the aid of electric rollers.
"I know only too well the evil that I propose, but my inclinations get the better of me."
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Re: Opinions on Aftermarket Magnetos Sought

Postby Mutt » Sat Mar 23, 2019 7:58 pm

I see NOS FM coils on eBay all the time for way less that $100, NOS points too, less than $20 on eBay
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Re: Opinions on Aftermarket Magnetos Sought

Postby jOe » Sat Mar 23, 2019 8:15 pm

What about rotors?
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Re: Opinions on Aftermarket Magnetos Sought

Postby Mutt » Sat Mar 23, 2019 8:38 pm

why would ya need a new rotor? Old rotors lose their magnetism, but they can be recharged (as they were dead before they were charged the first time)
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Re: Opinions on Aftermarket Magnetos Sought

Postby jOe » Sat Mar 23, 2019 9:09 pm

Well, if you want to take a shot at recharging it, I’d be happy to send it to you.
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Re: Opinions on Aftermarket Magnetos Sought

Postby jOe » Sat Mar 23, 2019 11:18 pm

The real question is, why did the rotor lose it’s charge so quickly?
And whatever the answer is, if I have it recharged again, would it lose the charge again?
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Re: Opinions on Aftermarket Magnetos Sought

Postby hayleyl » Sun Mar 24, 2019 3:56 am

Hello all - If you want to get your knees in the breeze and your butt on your old putt, Morris Magnetos are the go...full stop. Ripper reliabilty and a great robust product. Great for twin plugging on flat heads as well. Cheers Hayley.
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Re: Opinions on Aftermarket Magnetos Sought

Postby Ferrous_Head » Sun Mar 24, 2019 6:23 am

The coils ans points you see on Ebay may or may not be F< products. There are aftermarket coils being made. The genuine FM coils will have a molded in part number (FM part No.) - Q2477C. FM MIGHT be making them without this molded in part number but I don't see why they would stop doing that.
Points for magnetos aren't the same as points for battery/coil systems. Those systems only see at ,most 13 volts going through them.
Magneto points have very hard (and thicker) contact aces to help withstand the higher voltages tey see.
And condensers arem't condensers (they are capacitors in fact) but not all are equal. The one you REALLY want is a FM RX2433 but good luck with finding them in stock anywhere. Buy try old tractor dealers. All the commonly available capacitors mrsdure out to 20-25 Mfd's. The RX2433 is closer to 50.
These things DO matter when your trying to kick start your bike. The more things you do get right the better your spark will be and the easier your bike will start.
FM part number for the points is B2437A. While your looking for that elusive capacitor ask for a set of those points as well.
Oh. The points are liable to set you back 30+ dollars. You get what you pay for.
The part numbers I quoted are for the stock HD (FM) magneto. FM part number FMZ2-2c53A. If you have something else all bets are off.
As always, this is only my opinion. nothing more. I am often wrong about some things. (Been married 3 times)
"I know only too well the evil that I propose, but my inclinations get the better of me."
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Re: Opinions on Aftermarket Magnetos Sought

Postby elliot9797 » Sun Mar 24, 2019 10:15 am

jOe wrote:The real question is, why did the rotor lose it’s charge so quickly?
And whatever the answer is, if I have it recharged again, would it lose the charge again?


They will loose charge again just sitting-metal changes with age (Age Hardening) and I wonder if this doesn’t have something to do with why the rotors go dead/loose magnetism. These parts are 50+ yrs old

I just had a Fairbanks stock Mag Rebuilt by Dave at Morris. He went through the entire thing, new points, condenser, billet points plate, bushings in the housing for the shaft, new bearings, coil, Rare earth rotor, literally EVERYTHING but the body, cap, and base assy. I believe it was around $700-$800 to have done, but it will shock you so hard you can feel it in your toes just by the flick of your finger.

Spend the money, and have Dave do it. You will not regret it.
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