Timing (way) off?

B

Bobby Joe

Been Around the Block
So am and torn between if this should go in the Electrical or Engine section...

I have read a lot about setting the timing of the points and I thought I had it down, but then something interesting happened today that it totally confusing me, so I will try and explain this as clear as I can. First off, this is a 1971 CB500. I just installed a set of Dyna Coils DC8-1 5 Ohm ignition coils, along with new Dyna wires and NGK 5 ohm spark plug boots.


As most of you will know, cylinders 1,4 go together and 2,3 go together, both at the points timing and the ignition coil paring. Per the service manual, and by hand l, I set the Breaker Point Gap, messed up a time or 2 with the learning curve, and I thought I got it right. When I turn the crank by hand, the points separate to the specified spacing when I get to the 1,4 mark and same with the 2,3 mark.



Now that I have a new battery and coil+wires, I was able to check the timing with a strobe light. The red and black clips go to the battery terminals and the purple clip goes around the desired spark plug wire. (NOTE: I tried to manually set the timing with a test light/blinker with alligator clips and have not had luck...ever. Maybe I cannot turn the crank slow enough with an adjustable wrench vs a 23 mm socket, but I doubt that.)





When I connect the purple clip to:
  • No. 1 cylinder (coil 1,4): the timing light flashed when the 2,3 mark on the slipper passes by
  • No. 2 cylinder (coil 2,3): the timing light flashed when the 2,3 mark on the slipper passes by
  • No. 3 cylinder (coil 2,3): the timing light flashed when the 1,4 mark on the slipper passes by
  • No. 4 cylinder (coil 1,4): the timing light flashed when the 1,4 mark on the slipper passes by

How is the strobe connected to the 1,4 points/coil (No. 1 cylinder) flashing when the 2,3 mark on the "slipper" passing by? And then the strobe still goes off when the 2,3 point passes by when connected to the 2,3 points/coil (No 2. Cylinder).

So what gives. Have you guys seen this before? What do I do about it? Thanks :-\
 
You said:
"When I turn the crank by hand, the points separate to the specified spacing when I get to the 1,4 mark and same with the 2,3 mark."

Your points should be closed until the mark, at which point they should open, which will give you a spark.
The way I do it is hook a test light to the spring on the 1/4 point. Turn the crank until the points are as open as they get, set your point gap. Then turn the points plate so that your test light goes off/on (i can't remember) exactly when you hit the 1,4F mark.
 
For checking the timing with a test light, do you connect it like so?
7y5aja7a.jpg
 
Leave everything connected. With the ignition on, the light will go on when the points open. Or, you can use a voltmeter.
 
Ok. So the light turned on here...while connected like this...
So I am off of Tapatalk and back on the laptop. So the light is turning on before the F mark, and so according to the manual, I have some major adjustments to do. It is hard to think it is this many degrees off!!

ajevebuz.jpg

py6e6aby.jpg

atavyqar.jpg
 
Na thats not bad at all. I mean it wont run, but adjustment wise you're real close.
Loosen the 3 screws holding the plate on, and rotate it ever so slightly. Small movements here translate to much larger timing changes.
 
SONIC. said:
Na thats not bad at all. I mean it wont run, but adjustment wise you're real close.
Loosen the 3 screws holding the plate on, and rotate it ever so slightly. Small movements here translate to much larger timing changes.
Click to expand...

good to know. Thanks. Back out to the garage...
 
Set the gap and then just get it good enough to idle. After that, adjust timing using the strobe light. Way easier and almost always more accurate.
 
Sonreir said:
Set the gap and then just get it good enough to idle. After that, adjust timing using the strobe light. Way easier and almost always more accurate.
Click to expand...
The manual says, "rotate the crankshaft until the slipper on the contact breaker is coming up on the highest position of the cam lobe. Measure the gap..." According to the pic, this is when the timing mark is about the middle of the 1,4 || mark. I think someone on the forum said it should be either at the T or F mark...input on this??
 
Bobby Joe said:
"rotate the crankshaft until the slipper on the contact breaker is coming up on the highest position of the cam lobe. Measure the gap..."
Click to expand...

This is how you set the gap, NOT the timing. Spark happens when the points first break contact.
 
AlphaDog, it was a question in response to Sonreir telling me to set the gap first. I figured that I may as well double check that prior to setting the timing.

On another not, connecting the test light to the spring finally got it to work as I was expecting and now i can see it coming on when the points break contact as you are saying. (yes, I read that several times, but it makes all the difference when you finally see progress! Woo hoo!)

thanks dudes
 
You DO have to set the point gap first. If you set the timing, then the point gap, the timing will change when you change the gap.
 
AlphaDogChoppers said:
You DO have to set the point gap first. If you set the timing, then the point gap, the timing will change when you change the gap.
Click to expand...

+1

You always have to set gap before timing.
 
No! Fer fuck sake!
The timing mark is when the points just begin to open.
Follow the fucking instructions that YOU posted earlier. Sheesh!
 
AlphaDogChoppers said:
No! Fer fuck sake!
The timing mark is when the points just begin to open.
Follow the fucking instructions that YOU posted earlier. Sheesh!
Click to expand...

Lol. Sorry to fluster you. I think I am using my terms improperly.
 
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