Old Brown

Put scope on pickup. Looked about the same as the stock TCI pickup.
Tried taping a washer to top of pickup to see if pulse would lengthen. I need to compare scope outputs to see if it affected the waveform.
It does advance but not much. 7 or 8 degrees. Progress of some sort.
Ran the setup for quite awhile. No sign of box heating up.

Here's what's inside
61zsbjTbbpL._AC_SL1024_.jpg
 
The washer did make a difference. Gonna grab a 3/4 inch magnet at wally world and see what effect that has on the amount of advance. Will fab a piece of metal to add to the pickup and see what I get. At this point I'm convinced the width of the magnet sets the advance range When I swap the polarity of the pickup the spark is advanced by about 15 degrees when the negative pulse is first. Scope is really helping sort this out.

The CDI starts sparking at a very low rpm.
 
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Speaking of test stands. Eaglesnest Dragway. The Great State of Texas provides this for me and have been using it for making performance comparisons for many years.
35 years ago when 20 cars a day went by it was pretty much my driveway.
 

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Tried the bigger magnet and no change in the amount of advance.

Next steps
wire the gy6 cdi to old brown tci pickup and get the initial timing set without firing the coils on the bike.
Disconnect coils on bike .
Crank and see whats happens.


Meanwhile hook up the GN250 box to the test rig and see what I get with that.
 
Being able to view the electrons move on the mini black monolith is so helpful. Restored the test bed back to the small TCI sized magnet.Looked at the signal and stored a waveform at 600rpm and 1200 RPM.
Tried the bigger magnet and no change in the amount of advance.

Then put the bigger magnet and tried to record a waveform. Turns out that refrigerator grade magnets aren't strong enough for the pickup to sense. So when I had the strobe on with the big magnet it was sensing the small magnet in front of the bigger add on magnet so disregard the no change in advance comment.

The test bed waveform looks like the TCI rotor waveform so is a good simulation of the stock tci pickup. Next step is to stimulate TCI pickup from sound card buffered to the igniter . No more wobbly drill mounted stuff.
 
Since we were only just this side of points with the tci in the first place I don't think a relay with some sort of analog control to switch between pickups is all that bubba.
Agreed.
 
Some discussion about the gy6 box.
https://www.buggydepot.com/forums/viewtopic.php?t=3242


Installing the GY6 box and Banshee coils on Old Brown so we will see how it runs .

Jim
I'm trying to use connectors that match up to the stock 1980-81 harness. I don't have a tci harness so going by schematics. Can you confirm the TCI igniter box connector on the harness matches what I'm spewing The pickup colors are an item of interest.


Image deleted because it was wrong.



Goal
To unplug stock TCI box and plug in GY6 box.
Replace stock coil with Banshee coil.
Plug orange coil wire to new coil. Ground other connector on coil.
 
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Jim thank you. Exactly what I needed. Twomany and I had lunch today and he came out to the house to look and see what I'm up to on this. We talked about a circuit to sense when to switch pickups and he gave me some good ideas to explore. He likes the little Honda cdi boxes.
 
I have deleted previous wiring diagrams because there were mirror images on the harness connector.
This one is correct thanks to JimScreen Shot 2020-03-11 at 11.35.21 PM.png
 
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Well I joined the small bottle of nitro pills in the top pocket club last week. 4 days in ICU.
Spent the last couple of days upgrading the Mac in the Monks Cell. 50" 4k monitor. works amazing well. Had 42" before and some of the text was a tad small. Bought a name brand this time and oddly a huge improvement in video playback. Can't put my finger on why the difference but it is instantly noticeable.
Supposed to warm up this week so hope to be out in the barn working on TCI boxes soon.

Cheers
Jack.
 
Hey Jack---Glad you are home and doing better, hopefully you will not be needing your nitro pills. This is time to keep going but not to overdo it......

tim
 
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