1980 NO SPARK Troubleshooting....What am I missing?

Check the pickup (trigger) coils. Check 'em at the connector going into the box and you also verify wiring up to that point. You should get 700Ω's across each coil and 1400 across both. I'm not sure on the coil colors, but you could mix-n-match different combo's to see if that makes a difference?
 
this main power inlet diode or transistor has continuity Both ways, Meter leads switched. That means she’s shot right?
You can't check an individual component with it still connected to the board. It has to be isolated (desoldered) so you don't get feedback through the board. That diode (D4) looks cooked?

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According to sledog83

to check the output transistor. That’s the big one on the heat sink. Just probe it base to emitter, base to collector, emitter to collector. Try it with the probes switched around. You should see conductivity one way, but not after switching the probes around. There might be a better explanation in the tech section. There are replacements for the output transistor if you need them. I have a substitute, but the part number is not at my finger tips. I have repaired a couple of these boards already, so don’t worry. It can be resurrected.

On the earlier enclosed igna.png orange goes to the Transistor as it also looks on the picture
the black with three legs up at the left corner text
97
EID 41
-035
 
Jim i will check with it disconnected. I am not familiar with these boards and didn’t even consider your point. Thanks. Jan P I checked 97
EID 41
-035 and found that the lower 2 legs from top of original pic have continuity to base in diode mode both ways(leads swapped). Top does not
 
Jim i will check with it disconnected. I am not familiar with these boards and didn’t even consider your point. Thanks. Jan P I checked 97
EID 41
-035 and found that the lower 2 legs from top of original pic have continuity to base in diode mode both ways(leads swapped). Top does not

I am not good at transistor functionality ..and there are different types ..lets wait on Mr sleddog83 before anything is soldered out.

If I should guess that is broken
continuity to base in diode mode both ways(leads swapped).
 
ZD4- That is the 8.2 volt zener. This is a common failure point. Those are easy to get. A replacement is 1n4738. Check it again with your diode checker on the meter with it disconnected. This regulates voltage on the board. It definitely won't work if this is shot. A word of warning.. these version of boards have delicate solder runs onthem. You need a delicate touch when working on them. Too much heat with an American Beauty and you will rip the solder run right off. Do you know anyone there who is handy with a soldering iron?
 
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lets wait on Mr sleddog83 before anything is soldered out.
I wasn't telling him to de-solder anything. I was pointing out that if you try to measure a component while it's still in the board, you'll have no idea what you're looking at. Look at T-whatever below. Lets break the emitter inside the transistor. With it still attached to the board, you'll never know it because the meter will read across R-whatever because it's still soldered to the board and that happens to be the path of least resistance. What did we learn? Nothing. We learned there's still resistance there but we have no idea if it's from the component... or another component in the board. If we want to measure resistance of the component, we'll have to isolate it.

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I wasn't telling him to de-solder anything. I was pointing out that if you try to measure a component while it's still in the board, you'll have no idea what you're looking at. Look at T-whatever below. Lets break the emitter inside the transistor. With it still attached to the board, you'll never know it because the meter will read across R-whatever because it's still soldered to the board and that happens to be the path of least resistance. What did we learn? Nothing. We learned there's still resistance there but we have no idea if it's from the component... or another component in the board. If we want to measure resistance of the component, we'll have to isolate it.

View attachment 178602

Yes Sir we are on the same page ..Bare with me My English can lead to errors not intended
 
Here's another path you might want to consider Rich. A $20 Suzuki GN250 igniter box is a viable replacement for the TCI box. Have a read here.
There's currently 8 or 10 bikes running this thing with no problems so far... including mine. At 20 bucks a pop, you can afford to carry a spare in your pocket.;)
Here's the pin out for the GN box.

Pigtail Wiring V2.png
 
this main power inlet diode or transistor has continuity Both ways, Meter leads switched. That means she’s shot right?
The part you have circled is a resistor so it should conduct both ways. If a resistor is bad it usually looks burned. Those four egg-shaped diodes in the upper right, check them because they are made out of glass and are fragile. You can leave those particular ones in the circuit when you test them. ALSO -- check continuity through all your connectors by back probing them. Don't forget to check your coil with a meter. Finally, I didn't notice what you are using to trigger the whole thing, but I wouldn't trust anything but the normal stock arrangement if I hadn't seen it work before
 
I was looking at your diagram. Seems OK. Not really sure if the Pickup coils are hooked up right. I have to assume TC Bros did their harness properly. Because you are using different color wires for the pickup coils, we can't really tell whether it is right just from the diagram. If the PU coils are not hooked up correctly, it won't work. Each coil has to connect to the right input on the board. They are 25 degrees apart and just won't drive the TCI module correctly. It won't burn up the board, but it just won't work. With respect to what Jim was pointing out earlier, you do have to be careful checking the components on the board. In the case of ZD4 which has that darkish look about it on the photograph, if you put an ohmmeter across it, you will likely measure the large 82 ohm resistor that is parallel to it. If ZD4 is blackened, and I can't really see that clearly, then it likely burned up. Not a big deal. Just replace the diode. These diodes cost maybe a buck at most, but you have to be careful replacing them. they only go in one way. Your measurements on the output transistor didn't sound great, but they didn't sound bad either. More like something wasn't quite right in the way you measured it. Jim's option of the alternate TCI might work. The guys seem to have put a lot of effort into it. If you are looking at buying a replacement TCI board, this might be a good option. If you really want to get this board working, and have the time to spare, you could send it to me and I could check it out on the bench properly, and upgrade the electrolytics at the same time.

Drifted off to sleep last night realizing I made a mistake in this post. That 82 ohm restor is not in parallel with the zener diode. It is in series. sorry. There is however a capacitor in parallel that will throw off any on board testing. In truth, all on-board testing with a meter should be taken with a grain of salt. It takes a bit of experience to know when to trust what you are seeing on the meter and when not. All component testing starts with a good visual inspection, which is why Jim immediately pointed out a suspicious looking zener diode. Off hand, I would say the rest off the board looks good and is easily salvageable. ....Got to stop falling asleep dreaming about motorbikes and TCI stuff.
 
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Jim's option of the alternate TCI might work. The guys seem to have put a lot of effort into it.
Mines got about 500 miles on it now. I did have to file the top hole in the trigger to get the advance more or less where it needs to be, but I can't tell the difference between the 2 boxes... seat of the pants-wise anyway. They both feel the same.
Here's the first run video.

 
I just ordered a GN250 box from amazon, arrival Wednesday. Sleddog i have all winter to finish this build, I may take you up on the offer to troubleshoot/repair this box. I do have another XS missing the tci box and wouldnt mind having GNs and stock working boxes. Jim did you just grind down one of the rivots to allow the trigger coil to pivot? I started reading the thread link on the GN conversion you posted. Seems like little to no adjustment is needed to be functional? Some folks are talking about installing a new magnet on the rotor and such, perhaps fine tuning?
 
Mines got about 500 miles on it now. I did have to file the top hole in the trigger to get the advance more or less where it needs to be, but I can't tell the difference between the 2 boxes... seat of the pants-wise anyway. They both feel the same.
Here's the first run video.


Just as Friendly input
Difficult to hear indoors and not knowing if cold or warm start and online like this ...
But first impression is that it is running a bit rough ..
It of course depends on mixture and wear ( mileage )
I don't believe it is the ignition To me it sounds as if Valve play is rather large.
Checked lately and are set to what ?
Some set them loose " Better to hear than to smell Valves "
And I suppose it depends on climate and riding style
But again first spontaneous impression. And cold start can be loose valve play. It sounds a bit like that.
( This year I started up a rebuild and noticed a sound like that especially after a short stop and restart warm
Play was out of specs and it got better after a re adjustment )
Gets more quiet with warmer engine. Out on the Highway
I would check valve play and perhaps set ignition a fraction later .
Observing starting difficulties and throttle response..
 
Just as Friendly input
Difficult to hear indoors and not knowing if cold or warm start and online like this ...
But first impression is that it is running a bit rough ..
It of course depends on mixture and wear ( mileage )
I don't believe it is the ignition To me it sounds as if Valve play is rather large.
Checked lately and are set to what ?
Some set them loose " Better to hear than to smell Valves "
And I suppose it depends on climate and riding style
But again first spontaneous impression. And cold start can be loose valve play. It sounds a bit like that.
( This year I started up a rebuild and noticed a sound like that especially after a short stop and restart warm
Play was out of specs and it got better after a re adjustment )
Gets more quiet with warmer engine. Out on the Highway
I would check valve play and perhaps set ignition a fraction later .
Observing starting difficulties and throttle response..
It sounds and runs just fine in person Jan. :cheers:
 
That looks and sounds good. I wouldn't mind putting one of those boxes on my test jig and computer and map out the advance curve. I probably won't switch over though. Got two good refurbished TCI modules already. Is there any way to reprogram those gonzo boxes?
 
That looks and sounds good. I wouldn't mind putting one of those boxes on my test jig and computer and map out the advance curve. I probably won't switch over though. Got two good refurbished TCI modules already. Is there any way to reprogram those gonzo boxes?
Not that I know of. I've got a spare that I cut open and JB Welded back together. It works fine (I ran it after for a while). Be happy to let you borrow it for testing. Don't know how far you read into that thread, but there's 2 types; one with a grounded trigger signal and one with a floating input. This one's a floater. What type gets shipped is random.. but both work just fine in the XS. PM me if you want to look at it.
 
Did you just grind down one of the rivots to allow the trigger coil to pivot? I started reading the thread on the GN conversion. Seems like little to no adjustment is needed to be a functional ignition swap? Some folks are talking about installing a new magnet on the rotor and such, perhaps fine tuning?
 
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