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Discussion Starter · #1 ·
I bought a 76 kawasaki kh100 the other day and have since been trying to get it running. I've skipped putting on the wiring harness and battery, since I know you can start the bike merely with the ignition coil and magneto hookups. I'm curious though- after attaching the original ignition coil wire (single black wire) to the black wire that came off the magneto (1 of 5 wires) I found I was getting a spark at the plug, which means I'm getting voltage at the coil, but no start. Is this a carb problem? Or do I just need to hookup the wire harness, get an ignition switch and do it that way (I'd prefer not to, rather just kick start) Am I connecting the ignition coil wire it to the right wire?
 

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2009 Ninja 500r
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Could be a lot of things, have you done a compression test? Anytime you do what you're doing it creates a lot of variables.
 

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Biker
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Hi Ann,

I saw the diagram the other day, mag had two coils so I am guessing one worked the ignition coil.
This is a low tension job, OR the bike's ignition could run off battery, probably a better spark too.

If hooked up wrong, one mag wire might be going to ignition coil and if other side of coil is grounded,
kicking engine over will cause mag to put out a.c. voltage and get jacked up though ignition and you
could get a spark at the plug but not 'TIMED' to fire when it is supposed to.

I did NOT see any points on that diagram. This is a weird set up. I know one mag coil went to a rectifier
to keep battery up.

Yes Ann, you can run bike off just the magneto, BUT there has to be one wire hooked to the points, that wire would go to
one side of the ignition coil, other side of ignition coil back to magneto, that will work, I have been messing with this stuff
for 40 years. The points could be under where the magneto is or like in my old Honda SL-125 up by the head where the
cam shaft is. assuming the points are set proper, I'd say the bike should start right up when wired as I mention, off the
magneto. So look around and see if you can find another wire coming from the engine. It would be just one wire.

I don't put much trust in the diagram I saw, it should have shown the points/condenser, but I think I know how to figure
it out. If you don't have a multi meter then get a tail-lite bulb same voltage as bike system with a socket and two long wires
to make a tester. PM me if you want to.
 

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Discussion Starter · #4 ·
Hey Ray, so I read your response about the ignition coil. I think you're right- one wire is grounded and the timing is off. I attempted to hook the one ignition wire onto the positive wire from the battery, which created a spark but still didn't run. I asked a friend and he said that if I hooked that single black wire onto the lead wire (red one) after the fuse, it would probably work (i'll have to set up the wiring harness) Whats your take on that? So I'm really new to all this stuff- how do you reckon I fix the problem, in simpler terms anyway? Wire to wire stuff
 

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Biker
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Hi Ann, I found diagram, this mag has 4 wires bk pink ylw pink. I don't know much about the bike at all.
I guess the best thing you could do is buy the shop manual or go to a library and see if they have a large repair
manual for their bikes.

You talk about a single black wire from ignition coil to black wire from magneto, but the wiring diagram shows
a black wire from mag to black wire with white stripe or white wire w/ black stripe to ignition coil, yet the diagram
says it is for a KH100

If you can't get the shop manual, I say pull left side cover off and see if you can see the points and to what
color wire they connect to. Take power from ignition key to one side of ignition coil, other side of coil to points
that should get the spark to the engine at the right time, and the bike should start, provided carb is in good
condition.

Good Luck!
 

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Biker
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Hey Ray, so I read your response about the ignition coil. I think you're right- one wire is grounded and the timing is off. I attempted to hook the one ignition wire onto the positive wire from the battery, which created a spark but still didn't run. I asked a friend and he said that if I hooked that single black wire onto the lead wire (red one) after the fuse, it would probably work (i'll have to set up the wiring harness) Whats your take on that? So I'm really new to all this stuff- how do you reckon I fix the problem, in simpler terms anyway? Wire to wire stuff
Hello Ann, do yourself a favor and call me o.k. ? I left my # on a PM. You NEED to have the spark 'TIMED' This is a WEIRD set-up.
WHY? because every other system has power, 12 volts+ to one side of coil, the negative side of battery is always grounded to the
bike's frame. SO with 12 v+ on one side of ignition coil, the ONLY way it can work is through the points, when they close, the coil's
primary winding (low voltage winding) finds its path to ground though the points.

What you MUST do is to find the wire from the points, and if the points, when closed make contact with ground or bikes frame
that is good, so that wire from points should be connected to one side of the ignition coil, other side of ignition coil being hooked
to a hot wire meaning 12 v + through the ignition sw. so no one steals your bike.

As it is right now, it might be that one magneto coil goes through a set of points that are INSULATED from the bikes frame,
other side of points goes to the ignition coil, that would make sense for the ignition coil to be grounded, As the magnetic rotor
of the magneto spins over the magneto coil cores, electricity is being made, which goes though the points to the ignition coil.

Call me at 727-204-2767 I'll tell you how to get that bike running, lots easier this way.
 

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Discussion Starter · #7 ·
Sounds good Ray- I'll give you a call maybe an hour from now. I have to go out and get a few parts before I start tearing it apart.
 
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