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Discussion Starter #1
picked up a 74 cb550 that has no spark. i thought i'd be able to figure out, but i'm stuck. plus my comp has a virus (using a nintendo wii now) so ssarching for solutions is hard. i do have a multimeter, so even any links to how to check this out would be great. Also, i do have a new battery.
 

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points? condenser? coils? plug caps?

check your points to see if they are: 1) closing all the way; 2) opening when they're supposed to; 3) clean.

spark plug caps if resistor type 5K to 10K ohms
 

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Discussion Starter #3
points do close. with ignition on, kill switch on, i can make spark in points with a screw driver in between them and pulling it out. but i dont have spark coming out of the wire ends. i had a spare set of coils but that didnt help. dumb question, are there only 3 fuses? i've only found 3.
 

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Ok, Here is the primer on Honda 4cyl points type ignition system. It is a paired system, in that cylinders 1 & 4 and 2 & 3, share a common coil and points set. Therefore, if you have no spark at any plug then it has to be in what is common to both sets of points and coils. I believe that is power to the coils. That should be a black wire that both coils plug into. So, how is the kill switch? How is the ignition switch? With the ignition on and the kill switch in the run position, you should have 12V at the black wire the coils plug into. If not, find out where the electrons went.

Ken
 

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Discussion Starter #6
Tested the black wire that both the coil's black wire plugs into and it has 12 volts. So crap. I connect everything back up and I do not have spark coming out of the wires. I am led to guess that either the wires are bad, which I guess are permanely connected, or the coils themselves are bad. But both of them being bad? As well as the other 2 that I had on...? I ordered a manual so hopefully when I get that I can use the diagrams to figure out what the other wires going to the coils do. I'm not ruling out the points, though I know litle about them, I don't see any sparks in them while turning the motor over. Though I can shock the shit out of myself.
 

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If you have 12V to the coils then there must be a problem with the points getting a signal to the coils, since it is unlikely that multiple sets of coils would go bad. Although it is possible that you could have a problem with the ground to the coils. Are they securely mounted to the frame without rust between the coil and the frame? Back to the points, are they opening and closing? is the gap set? Are the yellow and blue wires not grounded out and connected well to the coils? The system is pretty simple, so it can't be too many issues.

Ken
 

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Discussion Starter #8
Thanks for all the help. Finally got rid of the virus so the comp's up and running again, and so is my bike. The points were both stupid pitted and gapped wrong. So fixed that to find that one of the coils was bad, so threw another on and now the bike starts up. Now I just need to figure out why "off" doesn't work on my petcock. Internet isn't being very helpful for that, I have it apart but I don't see anything wrong.

Someone said it should have a spring in it I think, but I don't gots that.
 
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