testing condensers and coils on a 79 xs650

sbtm

XS650 Enthusiast
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I rode the bike the last week in normal condition. The other day I went to go ride, bike would not start. Quickly found out neither side is producing a spark at all. With the key on I have 12v at the points, ignition fuse, plug wires (is that normal?). I looked in my clymer manual but was very unclear about testing the coils. The resistance of the condensers were around 50 on the 20k setting on my ohmmeter (high?) And I couldn't get them to spark like the manual says. I picked 2 up from napa but wont be able to install them till after the 4th. Am I heading in the right direction? Would it be likely for both condensers to go out simultaneously?
 
No, it's not likely for both condensers or both coils to go out at once like that. Those components can and do go bad but usually only one of either pair and a gradual degradation, not totally dead. What may have happened is you lost power to the coils. Test the R/W wires that hook to the coils. They should show around 12 volts when you turn the key on. The power comes from and through the ignition switch and the kill switch. If you get nothing, maybe one of those has gone bad. Usually a disassembly and cleaning of the contacts inside will fix them. You can also bypass them and directly wire the coils to the battery through a relay .....

http://www.wgcarbs.com/index.php?option=com_content&task=view&id=12&Itemid=26
 
The r/w wires on the coils have 12v as well. Initially I had only 1v coming out of the ignition switch, which it hought I had solved the problem when I cleaned that switch, but that was not the case. Am I supposed to have the same voltage for the brown wire and the red/white on the coil?
 
Made the push late last night (2am) and put the new condensers in... works like a charm... though now I have no headlight, appears to be no voltage coming from single yellow alternator wire.
 
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