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Spark plug problems

jcoop86

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Looking for advice on my 1981 cb750f, I have been trying to chase down a running issue for a couple weeks, low power, backfiring, slow rpm pickup. The other day I accidentally got ahold of the champion resistor spark plugs not knowing they were resistors and put them in, weird thing is that it ran amazing. It would tach out in neutral amazingly fast. Now my question is do I have a problem with my ignition system like my cdi box, wiring or coils etc. or does the difference in spark cover up a different problem. It does run a little lean due to pod filters but the carbs are recently rebuilt and are perfect inside. Just wanna make sure I head in the right direction trying to figure this out
 
It's not the resistor they do better without it. You open the gap a bit more to add resistance back in. Where do you want it, inside plug to be useless or outside in combustion chamber where it can do some good?

Probably had a fouled or shorted across the porcelain plug in there.

There is NO CDI on these; I don't care what the manuals say, it is cheap transistorized inductive ignition, and I do mean cheap.
 
I've had 2 brand new sets of ngk in there and runs like crap even though I know that's the best plugs for it, but I pop those resistor champions in there and it runs pretty good. I'm just banging my head against the wall trying to figure out why that's the case, bad plug caps? Bad wires? Or are those resistor plugs compensating for the fuel issue somehow? I don't see how they could but the resistor plugs definatley cure some kind of issue with my combustion. I just for the life of me can't find the root cause
 
If still running OEM plug caps they are resistor and you should not run double resistors (plug plus cap). It kills your spark.

Check your caps and wires with a voltmeter, anything over 5000 ohms per foot of wire length is a problem.

Where I come from (the CB1100F website) pods are how you detune the engines to run ragged, they cause so much trouble you can't imagine. Mostly because of the CV carbs, they come from a universe where things are not as they are here on earth. When you lose the airbox off CV carbs you have put yourself in a world of hurt, ain't no other way to say it. The slide action drops way off with pods and no way to get it back. Then you jet up for pods not realizing that the pods have richened the motor already. It makes for problems that most cannot figure out since the carbs play by a set of unknown rules to most.
 
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