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#820080 08/15/20 3:21 pm
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Can anyone tell me how to view when the points are opening on my on my 1949 a7 magneto with a light. Thanks Jeff

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jfligg #820086 08/15/20 3:38 pm
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It only works if you loosen the centre screw, to isolate the “live” point from the low tension windings.

Of course, with the screw loosened, the points plate may fall out of the tapered socket end of the armature. That’s why we usually use a strip of cellophane or a cigarette paper, not a light.


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Originally Posted by triton thrasher
It only works if you loosen the centre screw, to isolate the “live” point from the low tension windings.

Of course, with the screw loosened, the points plate may fall out of the tapered socket end of the armature. That’s why we usually use a strip of cellophane or a cigarette paper, not a light.


+1, I always did this with my father, he’d fit the AAU, and I’d control the end which the points were at. When I got the points at the fag paper gap then he would fit the AAU and tighten it up.


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jfligg #820121 08/15/20 9:25 pm
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Hi
A gadget like this makes it easy and gets rid of all the faffing about

https://www.themagnetoguys.co.uk/magneto-static-timing-light

Plenty of versions or kits to make your own out there

John

Last edited by chaterlea25; 08/15/20 9:26 pm.
Ignoramus #820156 08/16/20 8:21 am
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Originally Posted by Ignoramus
using an ammeter set on ohms is pretty good .........needle drops to zero the second the points open

That doesn’t work on a bike with a magneto.


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chaterlea25 #820157 08/16/20 8:24 am
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Originally Posted by chaterlea25
Hi
A gadget like this makes it easy and gets rid of all the faffing about

https://www.themagnetoguys.co.uk/magneto-static-timing-light

Plenty of versions or kits to make your own out there

John

Only £38!

And anyone who finds the cig paper method this difficult shouldn’t call themselves a “Magneto Guy.”

Originally Posted by Themagnetoguys
Why can’t I use a piece of cigarette paper between the points?
Well, you can – but you need an extra hand to tell when the paper has come loose


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jfligg #820172 08/16/20 1:55 pm
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i uaed to put a cigarette paper between the points contacts, and then hang an alligator clip from the paper to make it heavvier

when the thing clattered to the floor i called it open


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chaterlea25 #820176 08/16/20 2:10 pm
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Originally Posted by chaterlea25
Hi
A gadget like this makes it easy and gets rid of all the faffing about

https://www.themagnetoguys.co.uk/magneto-static-timing-light

Plenty of versions or kits to make your own out there

John

Thanks for that ... been wanting one of those for years. Order's in. Who's got "cigarette papers" around the house any more anyhow? Brit smokers do because every one of them that I know still "roll their own" because of the taxes, but everyone here has been buying ready-mades for 40 years ...

Lannis


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jfligg #820183 08/16/20 2:34 pm
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But I guess every home has pieces of cellophane around--used for packaging of virtually everything.
An everyday substitute for fag paper in this context.
HTH

jfligg #820188 08/16/20 3:12 pm
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A fag paper or similar will not determine where the points break, it will determine when the points are open by the thickness of the paper.
Do you use Rizla red or Rizla blue? the timing will be different with each


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Andy Higham #820192 08/16/20 3:44 pm
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Originally Posted by Andy Higham
A fag paper or similar will not determine where the points break, it will determine when the points are open by the thickness of the paper.

Yes, but so what?

Ride 500 miles and the timing will have changed by more than that cigarette paper discrepancy.

If you really want to distress yourself, check the timing on your 1949 A7 with a strobe, at high rpm.


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jfligg #820215 08/16/20 6:08 pm
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I must admit it always takes me about three tries to get it right----with the points moving slightly on the taper as I tap them onto the taper.
IMHO it doesnt make that much sense to try to apply 21st century accuracy to 1950s technology.
Ever wondered why the ignition timing is 5/16" BTDC rather than 0.305" BTDC?
Probably because the factory got the timing adjusted for good power and the fitter measured the timing with a 6" steel rule.
Just my two cents worth of course.

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jfligg #820217 08/16/20 6:26 pm
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thats worth more than two cents.

but even so, if you hold tbe 1950s technology to precise and repeatable configurations that are tighter than "good enough," tberes useful power to be found.

its like where i live. the old surveyors with steel chains lined up tbeir property boundariez with 18th century technology. good enough for the time.

but these days using lasers the surveyors often discover extra pieces of unowned land that actually separate tracts that people thought joined edge to edge. these get sold by the state at auction for a profit.

applying modern thinking to old technogy sometimez reveals extras that nobody knew were there to take advantage of.


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jfligg #820220 08/16/20 6:41 pm
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According to a surveyor, when they encountered dense woods , dead reckoning might be used...Or today GPS will get you close...
I just look at the pits to see when they crack open...And it also takes me a few times to be satisfied


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jfligg #820230 08/16/20 8:20 pm
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Hi All,
Quote
I must admit it always takes me about three tries to get it right-

Before you set the timing assuming ATD/ pinion / sprocket removed degrease the tapers with your favourite degreaser
rub a little chalk dust on the taper and rub the faces together to spread out the chalk
Then when you have the timing set by your chosen method a light tap on the pinion will lock it onto the magneto enough to tighten the nut without slipping

The audible/ visual magneto gadget is great for working single handed and for those with failing eyesight

Works for Me
John

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jfligg #820240 08/16/20 10:13 pm
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Thanks for the chalk tip, john--I will try that next time.
Never too old to learn eh?


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