Author Topic: using a multimeter for timing  (Read 6397 times)

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Offline 750K2

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using a multimeter for timing
« on: May 05, 2008, 05:53:47 PM »
i'm pretty new at this motorcycle business and i just got through setting the lash on the rockers and the gap on the breakers when i finally decided to check the timing.  i don't have a dwell meter, don't have a lightbulb with aligator clips to hook up to the battery, don't have much else but i do have a multimeter.  i read through my cheesy 'how to honda' book with their description of timing, points etc, and found that all i'm doing is checking a circut for continuity at a certain position.  all that remained was to figure out what all those little wires were under that shiny cover and which ones open and when.  it turns out that if you pick a set of points, say 1/4, and remove the wires connected at the post you can clip one end of the multimeter to that post and the other probe of the meter to the wire harness (not the condenser wire).  set the meter to read resistance and then rotate the crank by the large nut until you position the 1/4 F mark under the casing witness mark.  loosen the three phillips screws and rotate the plate until the circut flips over to read "1"/infinity as in resistance. tighten the plate and do the 2/3 in the same fashion.  a closed circut reads pretty low resistance so it's either open, or closed.  too bad my cheesy book says F is where the circut is 'about' to open.  i hate ambiguity..fricken circut is either open or frickin' closed. so i picked F and that's where resistance goes to infinity and my plugs will hopefully fire.
here are two pics to illustrate.  only one probe is touching the wire harness and the second probe should touch the post.  definately get a set of aligator clips if you try this.  it would make things much easier. 
any comments?  did i mess this up?
frank

Offline TwoTired

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Re: using a multimeter for timing
« Reply #1 on: May 05, 2008, 05:59:57 PM »
You could set the meter for DC volts, leaving the points hooked up, and the meter leads across the points contacts, or whatever they connect to electrically.  When the meter goes from zero to a higher voltage is when the F mark should align. (Keyswitch on)

The meter then gives you the same info as a lamp with two wires and a alligator clips.

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.

Offline 750K2

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Re: using a multimeter for timing
« Reply #2 on: May 05, 2008, 06:05:02 PM »
thanks! another way to skin a cat.  i'll have to try it!  i'm just glad i didn't have to splurge and purchase a light bulb.
frank

Offline TwoTired

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Re: using a multimeter for timing
« Reply #3 on: May 05, 2008, 10:35:44 PM »
thanks! another way to skin a cat.  i'll have to try it!  i'm just glad i didn't have to splurge and purchase a light bulb.
frank

Yes, just think of how many fractions of a gallon of gas you saved!


 ;D ;D ;D
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.

Offline markjenn

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Re: using a multimeter for timing
« Reply #4 on: May 06, 2008, 12:00:08 AM »
Reading stuff like this makes me want to go out and hug my old Sears inductive timing light.

- Mark

Offline dpen

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Re: using a multimeter for timing
« Reply #5 on: May 06, 2008, 05:23:43 AM »
I have an old manual somewhere with instructions on doing your timing using as AM radio on a certain frequency - have to dig it up & post it

Offline Gordon

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Re: using a multimeter for timing
« Reply #6 on: May 06, 2008, 09:56:01 AM »
I have an old manual somewhere with instructions on doing your timing using as AM radio on a certain frequency - have to dig it up & post it

http://forums.sohc4.net/index.php?topic=17608.0 :)

Offline kghost

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Re: using a multimeter for timing
« Reply #7 on: May 06, 2008, 11:57:52 AM »
I use the multimeter method cept I set it to continuity....I like the beep.

Or I use my magneto timing box....it buzzes and vibrates  ;D
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