Points to GN250 Electronic Ignition Conversion

Jim

Congrates on getting the sound card oscilloscope up and running. Been wanting to try that for decades.


Since you have the levels adjusted to make your sound card happy on the inputs could you make a recording of the stock TCI pickup at idle and at higher rpm?

A sound card headphone output is around 90-200 ohms so should matchup pretty well to the Gonzo trigger inputs. Would allow exploring the min -max inputs to the gonzo and other boxes.
 
Jim

Congrates on getting the sound card oscilloscope up and running. Been wanting to try that for decades.


Since you have the levels adjusted to make your sound card happy on the inputs could you make a recording of the stock TCI pickup at idle and at higher rpm?

A sound card headphone output is around 90-200 ohms so should matchup pretty well to the Gonzo trigger inputs. Would allow exploring the min -max inputs to the gonzo and other boxes.
Yeah, when the snow melts.
 
Would this work as a trigger?

https://www.newark.com/littelfuse/55100-3m-02-a/hall-effect-proximity-sensor-0t012/dp/15J7660

15J7660-40.jpg
 
Not directly. That is a family of hall effect sensors most of which ether close and open a contact or latch closed. there is one member that is analog that with some buffering electronics could be made to work.

The RX pick works fine, is cheaper and works directly connected to the Gonzo inputs.
 
That looks suspiciously like a 3 pole cigar box guitar pickup...


Ding,Ding,Ding. Vanna tell the man what he won.


Would there not be rectifier/regulator issue re different polarity of brushes?

If you are using a Non tci stator cover with a converted rotor or a TCI rotor there is no need to convert the brushes. The rotor doesn't care which way the current flows through it.
 
Ding,Ding,Ding. Vanna tell the man what he won.




If you are using a Non tci stator cover with a converted rotor or a TCI rotor there is no need to convert the brushes. The rotor doesn't care which way the current flows through it.
Snopes rates this "somewhat true".
Many regulators act by opening/closing the ground side of the circuit. Early (up to 79) stator brush mounts have one brush permanently grounded to the stator, cuz early regulators open and close the HOT side of the circuit. Theres been a few found that an always grounded, ground regulated, charging system isn't a happy charging system. Why the "nylon screw mod" exists.
 
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The brushes just have to match the regulator.


Where I was going here was if the converted rotor is of the other flavor you don't have to change out the stator cover ,the brush holders and/or the regulator.

I think in the context of converting a non TCI engine to the rx pickup then the non tci engine will have a grounded brush holder and that works fine with a TCI rotor or a none TCI rotor with Jim's magnet conversion.

Glad this conversation occurred as I was not as clear as I could of been.
 
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Just to try to clarify, my solution to convert a points bike is to mount a TCI rotor and stator, but use the GN250 ignitor rather than the factory TCI box.
My question was about the wiring changes needed to get an 80 up TCI/generating system to play nice with a points model harness.
The solution seems to change the brush grounding and use the points model reg/rec. I have it to that point.
But the starter safety switch module may need to be switched as well?
 
I could be very wrong but I think the starter safety relay's only connection to the alternator is the yellow wire from the stator which works the same ether way. YMMV.
 
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