ideas on what happened?

[raindriver]

Sorry this has taken longer than expected.

I pulled the wiring harness, unwrapped it and tested, everything lovely-fine.

Still no joy. Hmmm?

Then I checked the wiring in and to the handlebars. Multiple exposed sections, lost insulation. Looks like I've found my problem. I'll post a pic or two when it's sorted.

[raindriver]

This is dragging on far too long.

I went over all my wires and connections, fixed umpteen current or future problems. But I get no spark at plugs.

There is 12V at both + and - small terminals on coil (when points closed). Until the green line to condenser/points is connected, when I loose power on - terminal. That doesn't seem right...there's no power to the points to do static timing, let alone start the motor.

Figuring this means bad condenser, I tried two others I have on hand (both seem to be for CB's). I tried using just one side of the OEM version (it has 4 wires, I used one side), and I tried an aftermarket picked up online (the kind with one yellow and one blue line, which looks to me to be two small 1-wire condensers). I also checked continuity, even replaced all wires in-between.

Something un-good is obviously happening when I connect the green. The new condenser is mounted on a steel bracket to the top engine mount bolt, so it's grounded. I've checked the points and plate, when energized it properly opens and closes the circuit.

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I'd be most grateful for any tips, pointers or suggestions on what I'm doing wrong, please!

[conbs]

Rainman, I have looked at your post a half dozen times. It does seem a little strange. Pictures might help. If I understand your problem, trouble starts when you connect the green wire at the points.

You might try disconnecting the green from the coil terminal then put a separate 12 volt source intermittently across the primary side of the coil just to make sure you get spark at the plugs. Green side must be grounded to the bike and then intermittently give the black terminal power. You can also check continuity to ground through both + and - coil terminals on the primary side. Make sure you can get spark out of your coil.

Green is your power wire to the points. Reconnect green to the coil (black still connected) and disconnect green from the points. Key on, do you get 12 volts at the green that is disconnected at the points? If you do and it grounds when connected to the points (points open), the problem would seem to be in your points. Make sure the little insulators are still in place.

BTW one of those small black spring clips for office use works well to hold the springs on the points while you are trying to reassemble the points connection. Let us know if this helps.

[48lesco]

You won't get 12V anywhere with the green wire hooked up and the points closed. What you have then is essentially a short circuit through the primary winding. Study the wiring diagram (I attached one if you don't have it). You get 12V across the points when they are OPEN and that's what makes the static timing method work - points open, light goes on. On the CA77's the condenser case MUST be grounded to the engine.

If all this is good, I usually start at the spark plugs, then check the caps and their connection to the wires. Check resistance between the two plug caps (through the coil) you should get in the 20K ohm range assuming you have 5K resistor caps. Make sure it's not zero or infinity. Open the points and stick some cardboard in there and make sure you get 12V at the coil and at the points terminal. report back...:)

[raindriver]

Thanks for suggestions, conbs and 48lesco. I have done all the checks you've mentioned, and am perhaps getting close to understanding the problem. Please tell me if you think these test results say I need a coil.

- resistance between plug caps (via coil, ignition not on) about 40K ohms.
- coil test (ignition on) with negative coil grounded, intermittent contact with black 12V to positive on coil does not produce spark at plug (grounded by contact with head).
- with cardboard in points, 12V present at coil negative and at points.

About a year ago when I had a good going-over of this bike, I looked at the coil and thought to myself I'd best line up a replacement. I have since spent many fun hours contacting dealers and parts houses, to no avail. (Tons of other useful/fun bits, but no OEM coil.)

I see one aftermarket version that looks a bit soft on the quality side, and read here people talking about the Dyna S, which seems expensive, and I'm not sure what model I need for the CA.

At least a new coil will fit if I go for the electronic ignition upgrade...

[conbs]

Rainman, sounds like you are making progress. 48 has hit on part of your problem with the resistance being a little high. Is it 40K on both sides? If it is not in the connection at the caps, it is looking like your coil has issues. Since it was running when you started having trouble the coil would seem to be more likely to me. Still, it is easy to clip a little off the spark plug wire to make sure there is a good connection.

With everything connected at the coil and the green wire disconnected at the points and key on, if you strike the green wire to ground, you should get spark at the (grounded) spark plugs as you will be replicating the effect of the points opening and closing.

It wouldn't hurt to make sure your points are absolutely clean as well.

Let us know.

[48lesco]

40K is a little higher than I would expect, but may be OK. Check resistance across the other two leads (primary winding). It should be in the single-digit Ohms but not zero. The coil in the picture is not OEM Honda and therefore you're a bit into uncharted territory. When you check for spark, both plugs have to be grounded - I would just screw the other side in to ensure a good ground. You should see spark on the other plug as you break the primary (black wire) circuit.