How Does It Work ???

snowhite

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:dunno: Hey guys',I've been searching sites on cdi ignitions can't really find an answer about how or what determines when or which spark plug fires,meaning the order of when they fire.I understand that the source coil puts out the charge but then what determines which coil gets the charge first?Is it all done by the cdi box?can you guys' help out? Thanks.
 

From what i understand the older style they all fire at the same time . there is a trigger sensor on the outside of the mag that i think controls it .Not for sure but that is basically how i understand it . Good Question
 
That would be the pick-up coil. It is fired by the pulse plates on the flywheel. The timing is set constant by the key in the shaft.
 
I do understand that the pickup/source coils by the flywheel generate the field.The wires coming from these two then go up to the CDI box do they not ?So now what exactly is the job of the cd to do with the signal ? Is this where each cyl. gets its designated spark?
 
The source coils(stator) give the power to the cdi. The pick-up coil is the trigger pulse that the cdi uses to fire the ignition coil for the cylinder. There are some race cdi boxes out there that can manipulate the timing by a couple degrees.
 
Hey taylzee,what kind of power do the source give for the cdi,question is what is it used for?What I'm trying to accomplish is to do an ohm test for both of the coils.I can test my source leads but for the pickup coil I cannot distinquish which wires to test!my clymer tells me w/r,w/g,I don't have this color code on my sled! the factory manual has a color of simular but there is no white wire or yellow,y/black! so I don't know which wire to test for resistance for the pickup.There is an orange wire that comes out of the cdi box and hooks to my spark coils.
 
KAPUSTA said:
Hey taylzee,what kind of power do the source give for the cdi,question is what is it used for?What I'm trying to accomplish is to do an ohm test for both of the coils.I can test my source leads but for the pickup coil I cannot distinquish which wires to test!my clymer tells me w/r,w/g,I don't have this color code on my sled! the factory manual has a color of simular but there is no white wire or yellow,y/black! so I don't know which wire to test for resistance for the pickup.There is an orange wire that comes out of the cdi box and hooks to my spark coils.

take off your recoil and trace the two wires from the pick-up back out to the harness... the pickup wires are usually in their own sheath near the magneto..

here's some good applicable reading... not necessarily for sleds but many concepts are the same... tj

http://www.jetav8r.com/Vision/IgnitionFAQ.html
 
Last edited:
KAPUSTA said:
:dunno: Hey guys',I've been searching sites on cdi ignitions can't really find an answer about how or what determines when or which spark plug fires,meaning the order of when they fire.I understand that the source coil puts out the charge but then what determines which coil gets the charge first?Is it all done by the cdi box?can you guys' help out? Thanks.

Both spark plugs fire at the same time. The plugs fire at the top and the bottom of the stroke.
 
TJ500 said:
take off your recoil and trace the two wires from the pick-up back out to the harness... the pickup wires are usually in their own sheath near the magneto..

here's some good applicable reading... not necessarily for sleds but many concepts are the same... tj

http://www.jetav8r.com/Vision/IgnitionFAQ.html

Now does anyone have any info for the ones in a sled?
 


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