Topic: what did I fry while timing my CB550?

[Chaser60]

Bike 1975 CB550.   about 8000 miles.   Stock airbox, filter and carb jets.   Just finishing a long winters build.   Thought I had solved all remaining of my gremlins and was looking to a nice ride today...NOT SO FAST !

Set timing yesterday with strobe.    all 4 cylinders were firing and all exhaust headers hot.   I could not quite get the F 1-4 to line up right (it was slightly advanced) and I had run out of adjustment on the plate for 1-4 and so I called it a night.   Today after some research, including the ignition FAQ here, I reset the gap on both points to high end of range 0.016 /0.017.  Then also did Twotired recommended shift of the main plate via a small (0.003)inch shim.   Got the 1-4 timing right on for both idle and advance works fine too.

Moved on to the 2-3 points and here is where the sparks flew...while loosening the lower screw, the screwdriver contacted the bolt that connects the condenser lead to the points.  NIce little short to ground and some sparks.   Next thing I see the timing light no longer is firing so I think "crap -  did I fry my timing light?"

Steps taken so far.   
1) timing light still fires when on the 1-4 cylinders, so the light is good.
2) pulled plug wire from 4 and checked for spark.   spark is present.
3) pulled plug wire from 3 and checked for spark.   None present.  Did this by installing a plug in the wire and laying plug on engine block.   Same procedure and same new plug as I used to test #4.
4) switched the condensors between 1-4 and 2-3.    retested for spark.   Same issue.   4 has spark, 3 has no spark.  Condensor ruled out as issue.

Could it be something with the 2-3 point settings?   Does it seem possible that I actually have fried the coil with this stupid gaf?   

I have a volt/ohm meter, but am not much of an electrical guy...How do I go about the next steps to trouble shoot this issue?

[Deltarider]

First you could check if points 2-3 short to ground. Sometimes the spadeconnectors make contact to the plate. This could have happened in the proces of setting. With ignition on, kill switch in run, you should read around 11 volts between the little bolt in the breaker points (where the wire connects) and ground when open.
If it is zero report back.
Oh and I don't think you've fried anything. You should carefully check if the center of the breaker points is still well isolated.
I suppose you didn't ment sparks were flying already between the points 2+3. Some little sparks are OK. To big indicates a faulty condensor.

[Chaser60]

Deltarider, thanks for quick reply.  I am getting 11.6 Volts from the 2-3 connection you outlined.   However, I did notice that maybe they are not ever really closing.  So I did same test you describe except when closed.   On the 1-4 side, when closed, i get zero, but on the 2-3 side I get 12.4.   Will recheck gaps and settings now.  Let me know if you suspect other issues.

As for sparks, there was no arching or sparks from either sets of points.   The sparks I am referring to happened when I shorted the little condenser bolt to the screw for adjusting 2-3 by mistake.  Small sparks ...not a fourth of july shower for sure.

[Chaser60]

Ok, so think I now have this solved.   When I shimmed the main base plate over per the twotired post in the FAQ, I failed to go back and check point gaps.   the effect of shifting the base plate to the 1-4 side opened the 2-3 gap so wide that they were failing to close.  Points that dont close, make it kinda hard to get spark ! 

Delta rider, the clue came in the volt test you outline.   12 volts regardless of open or closed tipped me that it was not closing.

Now will double check all gaps, and finish the timing job.   I hope.

Thanks a million.   Once again, my sanity is saved by someone on this forum.

Cheers

[lucky]

It is always best to set the points with the IGNITION OFF and use your ohm meter on the ohms X 1000 scale to set the points. No reason to have the key on and let the points sizzle.

"You can lead the horse to.............