generic replacement condensors?

Mike (MA) /

Hello,

My understanding of the condensor is that it's a capacitor used to protect the points from the high voltage spike that occurs when the points open. If that's correct, could any old 6V or 12V condensor from an autoparts store be used? In electronic systems and power supplies, capacitor values can vary wildly and not really affect the output measurably.

Thanks,

Mike

Re: generic replacement condensors?

That is basically true, but if you can make them fit you would need the correct voltage at least.... ie a 6v in a 12v application would create a weak spark and a 12v in a 6v application might burn the points prematurely.

Re: uf

The "u" is in italics and the "f" stands for farads. Put them together and you have microfarads.

Microfarads are the value of capacitance you want to match when you are replacing the condensor. If you know what the factory's rating is, try to get one as close as possible to that figure, which will match the coil's resistance.

Jim

Re: generic replacement condensors?

Ron Brown /

Mike,

I used a condensor from a Honda CB500F, 1971, on my Motobecane. I plugeed the hole in the magneto plate where the old, expensive, proprietary condensor used to mount. I mounted (grounded) the Honda cap to a frame bolt near the coil and connected it to the coil points terminal.

Dont worry about 6 volt vs 12 volt, these caps are rated about 150 volts anyway to handle the inductive spike from the coil. If you can match the , capacitance, that is good, but if not, try a lawn mower or motorcycle cap and keep an eye on your points.

I used to know a rule once that was something like; minus metal, minus capacitance, plus metal, plus capacitance. I think it refered to the fixed point. Obviously, this could be either way around so if you find pitting on one of the points, change the size of the cap and see which way it changes. Then post here and let us know. This info could help those who use a replacement coil too.

Ron

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