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magdyno capacitor

magdyno capacitor

Postby seattle##gs » Mon Aug 14, 2017 12:39 am

has anyone used the little green chips sold on ebay to replace the lucas magneto capacitor?

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Re: magdyno capacitor

Postby RoadScholar » Mon Aug 14, 2017 7:47 pm

The Lucas 2MC capacitor (Blue in color back in the day) was standard equipment on most British motorcycles also equipped with a zenner diode(s) and a full wave bridge rectifiers, which took their input from a permanent magnet alternator.

Is this the type of set-up you have?

The 2MC capacitor is currently available as a re-pop, but many other capacitors will do the same job, nothing special about the 2MC capacitor. If you are looking to eliminate a battery from a coil/points ignition system you may already have the solution.
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Re: magdyno capacitor

Postby seattle##gs » Mon Aug 14, 2017 9:26 pm

I have a magdyno on a 57 Goldstar. The magneto needs a full service . There is a small capacitor buried in the armature of the magneto and it goes bad with age. There is an aftermarket capacitor that is somewhat external and is easier to install.

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Re: magdyno capacitor

Postby Triton Thrasher » Mon Aug 14, 2017 10:22 pm

Some of these guys have used them.


Also some people on http://www.britbike.com
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Re: magdyno capacitor

Postby Beach » Mon Aug 21, 2017 5:36 am

I have used them on 2 Atlas with K2F mags...Over 3 years now and they function great...

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Re: magdyno capacitor

Postby 99cyclone » Thu Aug 24, 2017 2:07 am

The magdyno on my DBD34 was also recently showing signs of a condenser problem. I had planned on retrofitting the modern capacitor you are mentioning.

I disassembled the magneto and found that in addition to the capacitor going flaky, the armature winding insulation was on its way out as well.

The armature winding showed much lower than expected resistance, and a check on my growler indicated a short. External inspection of the armature was fine, but the 60 year old shellac insulation was breaking down from the inside-out.

The bike would start first kick, and run great...until it got hot.

You can try replacing just the condenser, but I think it's worthwhile to rewind the armature while you have it apart. There are multiple specialists offering this service, and the price isn't outrageous.

I am currently doing both - the rewind and condenser. Shipping out my armature this weekend for service.
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