'82 XS w/ no spark. Now What???

Wharfcreek

Near 50 Yrs of Experience
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So I got pretty frustrated today trying to get this '82 to fire. This is a 'project' bike, salvaged from the proverbial 'barn', and in fair overall condition at best. The good news was that the engine wasn't locked up, unlike the othre 'salvage' bike I have in my driveway. So, long story short, I pulled the carbs and did a cleanup and bench adjust on both of them last evening. But, before reinstalling them I wanted to at least make sure the engine fired. So, hooked up a battery, turned on the key, and with the neutral light showing green, I sprayed some starting ether in the ports and kicked it over. Nuthin!

LIke I said: Long story short.....so, to keep it simple, I did a bunch of continuity tests and confirmed good grounds throughout, and a healthy 12V at the coil and at the connector on the Igniter box side. I cleaned up contacts on the pickup, the block connector to the igniter, and up at the coil. I also confirmed good ground contact between the coil and frame. With no spark present, I got frustrated and ended up pulling most of the harness off the back half of the bike, pulled the battery box and removed the igniter box. So, that box is now in the house with me.

To the best of my knowledge there's no good way to 'bench test' the igniter box. But, I think one can pop the top cover and do a visual inspection and see if the box shows any obvious signs of failure.....like burned up parts on the board, cracks in the circuit traces.....broken components, etc. My unit is a '7-wire' type, and I've got 2 other units here that are 6 wire types. I believe the 7th wire in mine goes to some kind of relay that can otherwise be bypassed?

What I'd like to do is to come up with a known good coil, and possibly come up with some kind of way to simulate a running condition on the shop bench. If anyone has any experience with doing something like this, I'd love to know about it? What did you do for a 'trigger' mechanism (a substitute for the pickup pulse)? If I'm not mistaken, one can simplify the entire system by simply running a new 'positive' wire to the ignitor unit and coil, and then just make sure the 3 pickup wires are properly connected, and that the orange wire between the igniter box and coil has good continuity. Finally, a good 'negative' connection to the black wire on the igniter box. So, a 'known good coil' is necessary to run a simulation...... OR, I think a LED can be used here to at least see if signal exists. But, an alternative trigger would great too. Then the whole system could be tested OFF the bike!!

Anyway, if anyone has any thoughts on this, please let me know. And if anyone has a known good coil, that would be helpful to. My coil is off the other parts bike, and it's condition is really unknown. It could be my problem, or the pickup, or igniter box, and any combination of the 3. In fact, the only thing I know it is not, is the loss of 12 volts within the system. As that is confirmed, it's got to be coil, pickup, or black box.

Any help is greatly appreciated. Many thanks!! Tom D.
 
Update: Took the ignition box cover off, pulled the board, and inspected everything. Also tested the 4 diodes. Honestly, if I didn't know it was 40 years old, I'd have guessed it to be from last year. It was completely clean, no debris or contamination, nothing corroded, no 'spider webs', no junk or gunk....just a clean board, clean traces, clean parts, and.....well.... a perfectly good looking piece! Too bad there's no good test for it other than to plug it in to an otherwise 'running' bike and see if it too runs as it should. Oh well.......hence my desire to fabricate some kind of 'bench test' system. Would be nice to find a simulation source for the 'trigger'. I'm wondering if an audio signal generator would work? Anyone know the appx signal voltage that the pickup puts out? I've got an audio signal generator that I use for testing the amplifiers that I build. I think I can run it's output down to around 1/10 volt. I can probably run it down to about 20 hz, or maybe even less. By my calculation, 1000 rpm would be about be about 8 hz: 1000 (rpm) / 2 (4 stroke engine only fires every other rotation.....so 50% duty cycle at a 1K rpm idle) = 500 pulses per minute / 60 (seconds per minute) = 8.3 pulses per second......or in 'audio' terms: 8 hz (hertz, or 'cycles per second). If the output of the pickup were about 100mv, that's 1/10th of a volt. If an audio signal generator could be tweaked down to 8 hertz and 100 mv, that might make for a suitable 'input' to the control module. Thoughts?
 
That 7th wire on your later model TCI box runs to the sidestand relay and switch. You can simply remove them, no jumper wires needed. You could try your 6 wire boxes, just don't connect that 7th wire.
 
Anyway, if anyone has any thoughts on this, please let me know. And if anyone has a known good coil, that would be helpful to.
Testing the coil is easy enough. Power to one terminal, then ground and un-ground the other terminal. Grounding it charges the coil. As soon as you un-ground it, the plugs should fire.
 
Totally agree @Jim. The way to test a coil works is to apply power to the coil primary and then break the circuit. If you get a spark you have established that coil, ht lead, cap and plug work.

The alternative - finding your multimeter, testing the leads, measuring their resistance, subtracting this from readings, finding the coil specs, establishing tolerances, doing some maths, repeating this for the secondary coil, the ht lead and the plug cap and plug only tells you that the coil should work.

Of course, if you don't get a spark you can then spend half an hour testing each part to work out why it doesn't work.

Yours pedantically,

Dave
 
Does anyone happen to know the 'voltage' output of the pickup when triggering properly? I'm thinking that there's some kind of 'spec' for this, or perhaps someone has actually measured it. But, knowing that would be very helpful. I also am guessing that there's perhaps some way to test the magnetic aspect of the two cores in the rotor? Any comments on that, or any 'fix' if those are weak or bad?
 
Hey Jim,

To start, 'no, no spark at all!.' I have 3 TCI boxes (two 6-wire units and one 7-wire unit), 3 pickups (at least.....maybe 4), and only one coil. So, my plan is still to go back and check the pickup and the coil with an ohm meter and hopefully verify that one or the other is bad.....and replace it. I wish I had a spare coil...... but in the absense of that, I may just have to go out and buy something so as to be sure. But, the 'test' should be revealing.

Now, as to the 'reads' done in your threads: WOW!!! I'm impressed.......which I'm sure you've heard a number of times. I got through about 3 pages in one of 'em, then followed the link to the 60 page thread.......and rather burned out after reading all the posts in about 3 pages of that one, as well as watching the videos. But, the good news is that I 'think' I figured out what I wanted to know...which was: What is the stock output of the pickup sensor when being 'triggered' with the stock rotor. Please correct me if I'm wrong here, as I think the modded one you were working with was putting out nearly 1 volt. But, it looked like the 'stock' pickup sensor was doing about half that....yes? I don't know that I saw, or if you ever actually published this number. I rather deducted it from the DVM readings you referenced as you were in the early stages of all this.

Just to ask, is all this stuff now still available? Can I get one of those Suzuki TCI boxes still, and if so, where? Also, are you still doing the work on the rotors? One question that's been nagging me is; What's the condition of the magnets in my 'stock' rotor? I'd hate to find that all my problems were based on the failure of the magnets!!!

Thanks Jim!

Tom
 
Yes, the stock TCI pickup is much less than a volt.
I'm sceptical of the "weak magnet" theory. I'm probably at 50-75 TCI rotors rewound now and ain't run across a weak one yet. One way to test that theory would be to unscrew the sensor so you can wave a magnet across it and see if the coil fires. I've done that in the past and it's an easy valid test.
Back on page 1 of my thread I left a link to Jack's ( @Team Junk ) original thread where he started this whole endeavor. all the info on buying the box and how to wire it on a TCI bike is in there.
 
Yea, I'm still a little hung up on where to buy the box! Also, I've not yet read your thread far enough to see if you ever worked out the replacement pick-up part yet, or how you resolved the problem with the screw heads in the 'non-TCI' rotor. By the way, are you still re-winding rotors? I have one I may send your way, although I believe I also have a 'good' spare TCI rotor here.....or at least it 'ohms out' properly. I've not tested it or checked the magnets in it.

Ya know, I should mention this: I'm doing all this on a bike that I have no title for!! Lord I hope I'm not wasting my time and resources on a project that will end up going no where....... literally!! Oh well, I suppose there's always a market for a good running engine!!
 
Amazon has 'em. I think Wallmart does too.
I've got the replacement (we hope) pickup mounted. I'm waiting on some carb parts to test it.
Yes, I still rewind rotors. Have a look here. If you look on the last page, there's a modified rotor.
Give us some pics of the bike. We like pics here.

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Amazon has 'em. I think Wallmart does too.
I've got the replacement (we hope) pickup mounted. I'm waiting on some carb parts to test it.
Yes, I still rewind rotors. Have a look here. If you look on the last page, there's a modified rotor.
Give us some pics of the bike. We like pics here.

View attachment 190863

Wow. Did not the Gonzo came in different colors and sizes.
 
OK, I've ordered a couple of boxes from Walmart. And, thanks for the referrals! WalMart will advise me when they're on their way. For now, I'm still stuck with what I've got.

So, today I did some VOM tests of the spark coil and pickup. Results: Both pickup sections 'ohmed out' at 720 ohms, so I think the pickup is OK. The spark coil showed about 3 ohms across the primary side, and about 10K across the two HT leads on the secondary. And, ZERO continuity anywhere between the core laminations and any of the leads. This rather made me wonder: Isn't there SUPPOSED to be continuity between the core laminations and the secondary? Maybe someone can clear that up for me?

This leads me to believe one or both may be the problem: Either A) I've still got a wiring problem....which is entirely possible in a badly neglected 40 year old motorcycle, or 2) there is a component problem either with the TCI box or possibly still with the spark coil. Any comments here are welcome.

Attaching a couple of pics for your amusement! I'm guessing I'll get a comment like: "Send it to the crusher!"....but hopefully those enthusiast among the audience will prevail with positive commentary.

One last question, nothing to do with the above, but I appear to be missing a couple of parts on the rear swing arm. I see the adjusters are going in to air, and it looks like there's some end-caps missing? Anyone know about this, or where to get what I'm lacking?

Thanks to all!! Tom D.
 

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Yes, you're missing the end caps that go on the swingarm.
Re your coil: I'll repeat what I said above. "Testing the coil is easy enough. Power to one terminal, then ground and un-ground the other terminal. Grounding it charges the coil. As soon as you un-ground it, the plugs should fire."

And no, it's a floating secondary. It's not grounded to the lamination's.
 
ok, so tomorrow after the JB weld repair to the coil case cures overnight, I will bench test coil and see if I con produce a spark

In the mean time, are those end caps 'orderable' from somewhere?
 
In the mean time, are those end caps 'orderable' from somewhere?
Not that I'm aware of. You'll prolly need to source an entire swingarm. Ebay's prolly your best bet.

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