single coil with points????

MN_Bobber

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Can I run a dual output single coil with a points system? If so, how would I go about wiring that? I checked through the wiring threads, but I can't seem to find a points/single coil diagram.

Any information is greatly appreciated.

Sean
 
hi,,, from what i,ve been told by the guys that know ,,, use only 1 of the wires connected to the points,near the points.. isolate the other at the screw near the points,,, connect both coils to the 1 wire,,, when you set the timing,,, set to either side ,,,, r or left... .. alot of guys do have success doing it this way..... on mikesxs web site ,,,it does say something about the single fire lobe being a little bit out on the grind ,,but still works o.k. regards oldbiker
 
You can fire a single dual output coil with dual points. Simply hook the coil to both sets of points with a single condenser.

The problem is you will be doubling the duty cycle, the coil will have current flowing through it 50% of the time instead of 25% of the time. That means that it will only be off (allowed to cool) for 50% of the time rather than 75% of the time like the points system was designed to do.

Translation, the coil will get hot. You can still make it work if you use all the same work-arounds that Pete devised for his ignition; cut the plastic off of the mounting surface and bolt it securely to the frame so it has a heat sink.

My advise would be to use an automotive style, oil filled, can-type coil as they are designed to work at higher duty cycles.
 
The dual output coil will fire twice as a wasted spark on the electronic ignition so it wouldn't work any harder with a points set up. I have a duel output coil set up with my single points dual lobe cam and runs ok
 
Install new points lobe..... all you do is use one condenser out of the condenser pack, positive 12v to one side of coil primary other side of primary to ONE set of points....the other points doesn't get used or removed. Plug wires to plugs. Retime with timing light.
 
The dual output coil will fire twice as a wasted spark on the electronic ignition so it wouldn't work any harder with a points set up. I have a duel output coil set up with my single points dual lobe cam and runs ok

It's not the firing that cooks the coil, it's the dwell. The fixed duty cycle of points is extremely inefficient and puts a great deal of wasted energy through the coil.

Install new points lobe..... all you do is use one condenser out of the condenser pack, positive 12v to one side of coil primary other side of primary to ONE set of points....the other points doesn't get used or removed. Plug wires to plugs. Retime with timing light.

You could also do it without changing the breaker cam. Simply wire it as described above but also run a wire from one set of points to the other. You will need to time both sets of points. The advantage to doing it this way is that you don't have to buy a new dual lobe cam and you will be sure that both cylinders are timed evenly. From what I've read about the dual lobe cams, they aren't consistent from one cylinder to the other.
 
You guys sure are sticklers. I've said it before, I'm a numbers guy not an English major.

My comment should have read, "From what I've read about the dual lobe cams, they aren't always consistent from one cylinder to the other."

The point being, he could or could not have accurate timing with a dual lobe cam, but he can definitely time it correctly with the parts that he already has.
 
good conversation guys. I certainly appreciate all points of view and everyone's experiences. It's what makes this forum valuable for uneducated people like myself. Anyone got a diagram that I could use to get it wired correctly?

I'm a picture kind of guy :) Even a paint diagram would suffice. Thanks!
 
DualFirePoints.jpg


If you are using a dual lobe cam then only wire up "Points 1", if using the single lobe cam then also wire up "Points 2".
 
you have to buy the dual lobe cam for a single points setup (mikes sells them), the stock points system came with a single lobe cam for a dual points setup.
 
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