Author Topic: ignition timing testing  (Read 1536 times)

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keener

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ignition timing testing
« on: July 10, 2008, 01:56:49 PM »
I know that in the manual it says to use a 12V bulb when testing the spark advancer and I am wondering if there is any way to do it with a MM? perhaps know the ohms of the bulb and measure the current that you calculate...?

Chris
« Last Edit: July 10, 2008, 02:05:08 PM by keener »

Offline Dave-and-his-550

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Re: spark advancer testing
« Reply #1 on: July 10, 2008, 01:59:39 PM »
I don't think you need to calculate anything. You're just wanting to line the F mark up and make sure the light goes off on it right?

keener

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Re: spark advancer testing
« Reply #2 on: July 10, 2008, 02:00:05 PM »
yes, but I dont have a testing bulb...

Offline TwoTired

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Re: spark advancer testing
« Reply #3 on: July 10, 2008, 02:03:58 PM »
A 12v bulb is used for static timing.  You need to check dynamic timing when checking the advancer.  Usually, this is with a powered timing light.
  The advancer is two weights held in place with springs.  When the engine revs up, the weights fly away from the shaft against spring pressure and this rotates the point cam on the shaft and advances the timing.  Unless, of course the, weight pivots are rusted/gunky and won't allow the weights to move freely.

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Lloyd... (SOHC4 #11 Original Mail List)
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Offline Dave-and-his-550

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Re: spark advancer testing
« Reply #4 on: July 10, 2008, 02:08:49 PM »
yes, but I dont have a testing bulb...

I misplaced my digital camera, otherwise I'd show u a picture of the one I made. It consists of a $2 12v LED and two alligator clips that I soldered onto each wire of the LED. Or you could use electrical tape. It works just fine for static timing! Go to any auto parts store, and they'll have the two things I mentioned above.

Offline Scrubs

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Re: ignition timing testing
« Reply #5 on: July 10, 2008, 02:32:53 PM »
for static timing (not testing the advance) you can use the multimeter in the same way you use the bulb method.

Set your meter to continuity/diode testing so that when you touch the two test probe leads together you hear a tone.
Then connect as you would with the bulb method - by detatching the two leads attatched to each point.
attatch the red test probe (preferably with crocodile clips) to the terminal where you just removed the two wires from on the first set of points #1 & 4 and the black test probe to the main backing plate that the points are attatched to (or anywhere on the engine) You will possibly hear the beep, rotate the crank till the F mark of #1 and 4 lines up.
At that moment - when it it reaches the mark, the tone should stop, dead on the the F (just like a bulb going out) rotate the the main timing plate till you get it right. check the #2 and #3 points the same.

Make sure you have set your points gap first.

a handy thing to carry about are those electricians screw drivers, the ones with the bulb inside and crocodile clip attatched I have one taped under my seat with a spare set of points. Just attatct the clip to the positive battery.

pretty much any bulb you have lying around will work, indicator... etc
« Last Edit: July 10, 2008, 02:40:17 PM by Scrubs »

keener

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Re: ignition timing testing
« Reply #6 on: July 11, 2008, 12:05:57 PM »
when I do this the sound stops at about 4 places including the F mark when testing 1.4..... I dont know what  to do about it. It dosent seem to work when the 1.4 point is open. does this make sense?

« Last Edit: July 11, 2008, 12:25:40 PM by keener »

Offline TwoTired

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Re: ignition timing testing
« Reply #7 on: July 11, 2008, 01:47:29 PM »
when I do this the sound stops at about 4 places including the F mark when testing 1.4..... I dont know what  to do about it. It dosent seem to work when the 1.4 point is open. does this make sense?

No

What sound?
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

keener

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Re: ignition timing testing
« Reply #8 on: July 11, 2008, 01:49:05 PM »
the diode sound on the multi meter

keener

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Re: ignition timing testing
« Reply #9 on: July 11, 2008, 02:05:42 PM »
I am using a multi meter on the diode mode, should it stop when im on the "F"? if it should stop on the F how long should the shaft rotate till the sound comes back? ?

Offline TwoTired

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Re: ignition timing testing
« Reply #10 on: July 11, 2008, 02:33:25 PM »
OK, you have an audible continuity tester.  It should sound whenever the points are closed, and stop when the points are open.  You should NOT have the key switch on.  And, you should have your Stop-Run-Stop switch set to Stop.
 As you rotate the crank in the running direction, the meter should stop blaring when the F mark aligns.  If the point gap is set correctly, it should remain off until about 165 degrees of further crank rotation.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

keener

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Re: ignition timing testing
« Reply #11 on: July 11, 2008, 02:35:31 PM »
do i disconnect the blue wire?

Offline TwoTired

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Re: ignition timing testing
« Reply #12 on: July 11, 2008, 02:38:00 PM »
do i disconnect the blue wire?

If you put the Stop-Run-Stop switch in the Stop position, you don't need to.
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

keener

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Re: ignition timing testing
« Reply #13 on: July 11, 2008, 03:10:38 PM »
with the bike turned OFF and the kill switch to STOP the audible diode is always on meaning the buzz is always on....

Offline medic09

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Re: ignition timing testing
« Reply #14 on: July 11, 2008, 03:16:31 PM »
I have to say, you're good Lloyd!  8)
Mordechai

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Offline TwoTired

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Re: ignition timing testing
« Reply #15 on: July 11, 2008, 04:12:52 PM »
with the bike turned OFF and the kill switch to STOP the audible diode is always on meaning the buzz is always on....

If you have the meter clipped across the point contacts (post and engine case) and the meter is buzzing, then the points are closed, as you have continuity between the point contacts.  All the meter is telling you, is that there is electrical flow between the meter leads and whatever it is attached to.  It supplies it own power to determine this.

Assuming you already have the point gap set.  Now rotate the crank until the buzzing stops.  It should stop when the F mark aligns.  If not, you must loosen the three screws on the points mount plate, and rotate the plate (there are slots) until the F mark *does* align with the buzz cessation.  This will set your 1-4 points.  The 2-3 points has its own sub plate that moves on the 1-4 plate.  Set the gap first, then move the sub-plate.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.