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Discussion Starter · #1 ·
checking the ignition coil on 1976 CB500T, following the procedure in the Clymer manual.
shorting the 2 black/white leads and checking continuity to plug wires to compair for siimilar readings side to side.
with the plug connectors off the wires I get 10.3 and 10.4 ohms.
Q. does it matter what readings as long as they are the same?

with the connectors on the wires I get 19.0 ohms on one side, infinity on the other.

if I check continutiy of the caps alone I get 10.1 on one and 8.3 on the other.
the one that reads 8.3 when tested alone is the one that reads infinity when attached to the wire.
the reading follows the cap.
does this make any sense to anyone? do I just need new plug caps?
 

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Since the Haynes manual 'changes for 500T' section doesn't list anything about different coils, I'm going to assume they're either the same as or close enough to the 450 for this to be the start of an answer:
1. Anything between 9,500 and 11,000 ohms between the hot wires and the plug wires sounds fine. At least enough to run, if not perfectly.
2. The honda parts fiche doesn't indicate plug cap ('noise suppressor') resistance, but any cap i've seen is rated at 5,000 ohms. So yours sound a bit high and, for the price of new ones, are probably worth replacing. Especially since the springs that keep on the plug studs wear out a lot.
3. While you're at it, if you can spare an inch or so from your plug wires and still reach the plugs, trim them. they get stripped after you remove and replace plug caps enough times, and if they're bad enough that will add some more resistance to the circuit.
By the way, are you getting fire on either coil? If so, try trimming the wires and swapping your caps side to side to see if the spark moves with them. If you're not getting fire on either side, get new plug caps but maybe get a new condenser while you're at it.
 
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