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no spark

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mongeon:
I just bought a 74 cb550-four.  I have never worked on engines before, so please forgive me if I ask stupid questions.

I can't get the bike started.  I can't get the spark plugs to spark when I take them out.  The lights all work.  When I turn the key to the middle setting on the ignition, the oil light and the neutral light come on (when it is in neutral).  Sometimes I have to jiggle the key to get this to happen.  When I turn the key all the way, nothing works.  I don't know which position I am supposed to have the key when I start the bike.  I have tried it in both positions.  I had the engine cutoff set to run, and I had the fuel switch on.  I can't think of any more info.  Please help.

Chris

Bob Wessner:
You didn't mention it, and I don't mean to be condescending, when you say you can't get the spark plugs to spark when you have them out, are you grounding the plug to the engine when you do this? The outer electrode has to be grounded. Don't do it with bare hands though, use a dry rag.

mongeon:
I did touch the spark plug to the engine and hit the starter.  Somebody mentioned that I can just take the cover off and put a screwdriver in it, and touch the screwdriver to the engine, which I have also tried. 

Patrick:
I'm something short of an expert, but here's a couple things I might try. First, try to find out if there is fire going to the plugs. Find the distributor on the right side of the engine (as you sit on the bike). Trace the wires back til you find a connection. On my CB750 this connection is in front of the oil tank. I've never worked on a 550, so I don't even know if you have an oil tank, but I know the wires from the coils to the distributor have a connection somewhere along the way. Disconnect the wires, turn on the ignition and use a test light to make sure both wires are live. If they are, reconnect and go back to the distributor. Pull off the distributor cap. Touch the test light to the wire connection on each set of points and, with the ignition on, turn the engine over. The test light should flash as the points open and close. If it doesn't light, your points may be bad or dirty. Try cleaning them with some contact cleaner and try again. If you have spark at the points (this is all assuming you have points and not an aftermarket electronic ignition, with which I can be NO help)), then reconnect everything and pull a spark plug. Make sure it is clean and properly gapped. I usually get best results by touching the plug base to a spot on the frame where the paint has been chipped off. Of course, MY bike doesn't have any paint chipped off, since it is perfect in every respect (it's listening). If you have stainless steel crash bars, they work even better. Ground the threads to steel and try again. You have to make sure you have a good ground for the plug to fire. If after checking and cleaning all the connections between the coils and the plug you find you have fire at the points but none at any of the plugs, then I have no more ideas and I would type in a request for help to the SOHC-4 site - which, of course, you have done. Did I mention that I am something less than an expert?

rpyles:
I'll try a shot at it. On the 750 the ignition runs through the headlight bucket. If anyone's been in there, you could have a loose connection. The bike will crank, but no spark. This is the same as cranking with the kill switch in 'OFF'. Your ignition key should be in the middle position. The top position just turns on the taillight, and lets you remove the key, in case you have to park along a roadside.
Good luck.
Richard

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