K2 Magneto 1 sided spark.

hillbone

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Hi everyone. Heres my latest challenge.
Just had my magneto serviced. After fitting I have only the right side sparking. I have replaced the pick ups leads and plugs with ones off my Atlas that work and still no spark. The bike seems to run well on the right side so that tells me I have the timing right.
The bike is a 67 650 SS with no coils. Bewildered!.
Anyone experienced something like this?
Cheers and thanks.
 
Can be caused by wildly different points gaps or timing, between the two cam ring ramps.

Or a dirty or cracked HT slip ring, or an HT pickup brush coming out from the end of the pickup (too much spring and not enough brush).

It was a little bit negligent to fit the magneto before checking it had two sparks.
 
Triton Thrasher said:
Can be caused by wildly different points gaps or timing, between the two cam ring ramps.

Or a dirty or cracked HT slip ring, or an HT pickup brush coming out from the end of the pickup (too much spring and not enough brush).

It was a little bit negligent to fit the magneto before checking it had two sparks.
Click to expand...
Negligents a bit strong, perhaps "optimistic".
Points gap is 12 thou each and rings are exact. New points fitted in reconditioning with 2 new pick ups. Have tried other leads plugs and pickups with same result.
 
You will need to return it by the sound of it
What was involved with the service work?
I have seen a magneto body shim hanging out and shorting one side on a freshly reconditioned mag
Causing the same symptoms from memory
 
The internals that produce spark are the same for both sides. Thus, if you have spark on one side, nothing is amiss in the internals. The problem is in the slip ring outward. Clean and inspect the slip ring and brushes. Use new HT wires and caps. Do not use resistor wire or caps.The new Wassell brushes are soft ..... I once had a new one wear down to dust in 50 miles.

Slick

There is also the wild chance the points are so off center they are not breaking on one ramp.. ,,
SEE Resources pg. 7 for more info.
 
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Magneto chain off, then in a darkened room/workshop, turn the AAU forcefully to scheck if there is a visible spark at the housing, caused by electrical leakage, a small crack in the bakalite pickup housing, or some liquid.

- Knut
 
Good idea. I have returned the magneto to the repairer. He tells me it will be the points eartning out as both spark died the nect day.. I had supplied new points but he is going to recondition an older set as he tells me the "new" ones are usually not as good .
Thanks for all replies. The darkened room is a great idea.
 
He’s right about them selling poor-quality points these days.

I think the spring earths the spark if it touches the cam ring, if it’s the “modern” points with a steel base plate.
 
Triton Thrasher said:
He’s right about them selling poor-quality points these days.

I think the spring earths the spark if it touches the cam ring, if it’s the “modern” points with a steel base plate.
Click to expand...
Yeah. I supplied "new" points to be fitted in a "Lucas" packet. Apparantly plastic insulators and I will post the results when i get the maggy back. Been a 4 month turn around so getting impatient understansibly. I posted threads months before about points set up and diagrams etc.
Cheers mate from Australia.
 
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