Author Topic: Ignition Timing Issue (Getting No Ohm Change) - 74' CB550  (Read 962 times)

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Offline gmedia

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Ignition Timing Issue (Getting No Ohm Change) - 74' CB550
« on: March 10, 2014, 12:04:28 PM »
Hey All,

I've been trying to adjust the ignition timing, but for the life of me I can get any headway.

I purchased an ohmmeter and when I connect it to the based plate (or fins) and the points rocker (or blue wiring), I get get 0 ohms through the adjustment range on the plate whilst on the F mark for 1-4. It never shows unlimited resistance (or 1). I got my bike to fire up recently, but only 2-3 cylinders were firing. 1-4 were cold. It was firing on all cylinders a month ago just fine. Point gap was adjusted to .0014.

Not sure the best way to move forward, other than trying points/condenser tuneup or replacing ignition with electronic system.

Any ideas would be greatly appreciated.

Thanks all!

Offline Spanner 1

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Re: Ignition Timing Issue (Getting No Ohm Change) - 74' CB550
« Reply #1 on: March 10, 2014, 12:16:02 PM »
If you open the 1-4 points with your finger does the meter still show continuity?  ( i.e. 0 ohms or close to 0 ohms ) . If so , then either the Blue wire is connected on the wrong side of the insulating washer at the points , or there is a short to ground somewhere on the Blue wire ( rare )..... check that. Look at 2-3 wires for reference.       
If the meter says '1' while holding the points open, then the points cam is not opening the 1-4 points. This is caused by the points gap being set wrongly. The cam has a lobe and when the top of the lobe is directly under the points 'shoe' the gap must be 14 thou. Don't pay any attention to any F marks when doing this!. Just adjust the gap as described, then turn the crank until the 1-4 F mark lines-up with the mark . This is the 'firing' mark. Turn the whole plate to achieve firing at this F mark... Good luck.           
« Last Edit: March 10, 2014, 12:23:42 PM by Spanner 1 »
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....