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Biker
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Yeah and while you are doing that, might want to get a new condenser as well, one that is NOT working will pit up the points in short order, due to the 'back voltage' of the ignition coil. Do you want to get technical about it? points get closed, current goes through primary low voltage winding, building up a very powerful magnetic field. Points open, all that magnetic field that spread out around the primary coil suddenly shrinks or collapses back into the coil, not only inducing a very high voltage in secondary coil but also induces a voltage in the primary coil as well, that spark at the points is the result of back voltage when the condenser goes bad.
 

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American Legion Rider
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^^^^^^ Yep, what they said. Those points won't be worth saving if truly welded together. But I do wonder what would have happened to cause that. Points and condensers aren't very expensive so just put new in. And hope that's the only problem I guess.
 

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Biker
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Yes I wondered 'what in hell happened to cause that?' An ignition coil with a badly shorted out primary winding? Could it have been a six volt coil, mistakenly put in a bike with a 12 volt system? Will we ever know? Only the shadow knows.
 

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Discussion Starter · #8 ·
I Wound up separating the point and got it working mechanically at least, However the unit is still not making ground so ive placed an order for a new switch.

Is there a way to test the backing plate to see if it is still good? it was slightly rusted and I want to make sure it wasnt the issue.
 

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Save them all!
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If you have cleaned it up and there is no visible damage it's likely fine. A continuity test would tell you. One probe on the plate, one on the engine case should read 0 ohms.
 

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Save them all!
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Well, when closed they should have 0 ohms resistance across the points. The hot part of the point should have no continuity to ground when open.

Sometimes though I think some points become cursed and even after passing the above tests the bike runs better with a fresh set. Or that could all be in my head.

There is also a test for the condenser where you charge it and then discharge it against a ground watching for a spark (it's basically a large incapacitate.) A repair manual will spell that out. I rarely do it as they're typically so cheap I just swap them out when needed. Or go the electronic route.
 
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