Tri Spark woes

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RoadScholar said:
I suggest that my customers break, clean and re-make all electrical connections, check battery and charging system.
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Consider this little drawing:
Tri Spark woes


Very simplified - I know coils are not the same as resistors and I know there is some voltage drop in the Tri-Spark.

If the battery has 12.8 volts and each coil is 1.6 ohms then the combined coil resistance is 3.2 ohms. Therefore by Ohm's law Current = Voltage/Resistance = 4 amps. The voltage across each coil is Voltage = Current * Resistance = 6.4 volts and we're happy.

Now consider that the connector has built up a little resistance over time and it is now 1 ohm. Now the combined coil and connector resistance is 4.2 ohms. Therefore the circuit current is 3.05 amps. So, the voltage across each coil is about 4.88 volts and the voltage across the connector is about 3.04 volts.

Let's say that the coil normally produces 20k volts at 6.4 volts across the primary. At 4.88 volts, it will only produce about 15.25k volts! Not happy.

The sinister part is that the connector resistance builds up slowly over time and at some point, the connector starts getting hot which causes it to build resistance even faster.

I showed one connector, but in reality, in the coil circuit, there is a connector at the Tri-Spark, the other end of that wire either goes directly to the coil or to a connector with a wire that goes to the coil, there are four connectors on the coils and one of those goes to ground. Tiny resistances in any or all of those add up.

The other important circuit has several connectors and the kill switch - this is what feeds power to the Tri-Spark for its electronics.

BTW, this is not only Tri-Spark, it is all ignition systems.

As RoadScholar said, break, clean, and re-make connections. Personally,I clean the bullets with WD40 and use new bullet connectors. IMHO, the bullet connectors from British Wiring (https://www.britishwiring.com/) are superior to the originals - they are much harder to plug in as they are made of heavier metal.
 
I am throwing this out as a long shot.

Is anyone who is having problems with a Tri-Spark using unsuppressed relays to control the lights or horn?

My thinking is that maybe, just maybe, the electrical spike produced when the relay releases could be screwing with the Tri-Spark via the power supply.
 
arch said:
I am throwing this out as a long shot.

Is anyone who is having problems with a Tri-Spark using unsuppressed relays to control the lights or horn?

My thinking is that maybe, just maybe, the electrical spike produced when the relay releases could be screwing with the Tri-Spark via the power supply.
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Dunno. But what I can say is that I’m one of those who has NOT had a failure and I do NOT use any such relays.

So that kind of negatively supports your hypothesis perhaps.
 
I hate to weigh in o this thread, as I dont want to jinx anything.

I have a later TS with the test button. And a couple unsuppressed relays. No issues to date

Knock wood.
 
Marsgh, RoadScholar, you've been selling/promoting this product for quite a few years now.
Can you show us the advance curve of the later version?
 
some food for thought - this may or may not benefit anything with E-ignition systems, but make sure you have a good, solid, engine ground. while, the factory engine ground may be sufficient, it could be better. on my 74 Mk2, the main harness ground attaches to the head steady bracket for the engine ground. there was something about this that bothered me, so I added a secondary ground strap directly from the engine and tied into the main harness through the head steady bracket. the engine doesn't rely on the head steady for it's ground, but the head steady (bracket) now is a junction point for a direct path harness ground to the engine. doesn't take much - a short piece of 14 AWG should suffice.

also, if you've eliminated your Zener diode as part of the ignition upgrade, leave the associated ground strap terminated. this is a minor issue, and i'm no expert, but i'm thinking it also doubles as the frame ground.
 
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joe czech said:
but i'm thinking it also doubles as the frame ground.
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It depends on what you mean. If you mean as a ground for the electrical system, then, no, as the red wire is ground, not the frame.

A frame 'ground' if it actually was, ideally should bolt directly to the frame and not an additional component that bolts to it where there are painted surfaces and the chance the component could loosen and is (one reason) why the Zener has its own return wire attached to the Z-plate.

Edit: (If it wasn't for) the rear direction indicators that use the frame as part of the return where the L917 tail lamp is fitted then the frame wouldn't need to be grounded at all as everything else has a (red) 'wire return'.


If,however, you mean as a frame connection to 'ground' (as ground is the red wire) then not entirely necessary as there should be a red wire terminal (ring or spade) at the rectifier that grounds the frame to the harness but obviously does no harm to leave the red wire attached to the Z-plate.
 
ludwig said:
Marsgh, RoadScholar, you've been selling/promoting this product for quite a few years now.
Can you show us the advance curve of the later version?
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I cannot - it's not something I care about so I have not studied it. It's enough for me that engines equipped with them start without kickback, idle, run properly and are maintenance free.
 
arch said:
I am throwing this out as a long shot.

Is anyone who is having problems with a Tri-Spark using unsuppressed relays to control the lights or horn?

My thinking is that maybe, just maybe, the electrical spike produced when the relay releases could be screwing with the Tri-Spark via the power supply.
Click to expand...
My guess is no because Tri-Spark is tested to withstand 200volt spikes. That said, some voltage regulators can cause misfiring at 3000-4000 rpm so it's possible that relays could cause a misfire but I doubt actual damage.
 
gortnipper said:
From 2016

Tri Spark woes


https://www.accessnorton.com/NortonCommando/electronic-ignition-advance-curves.21964/
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Interesting, thanks for posting this.
The only ignition which appears to be always advancing with rpm is the Rita.
I've read that this is a big fault with Boyer but theres a nice flat there at the top end of the Boyer curve. Maybe the " always advancing with rpm" curve has been reconfigured with newer Boyer.
I'm not sure that the Trispark curve is exactly ideal at the top? Looks a bit out of control . Also, strange to see ignition timing pulling back with RPM, 5000-7000.
 
gortnipper said:
From 2016

Tri Spark woes


https://www.accessnorton.com/NortonCommando/electronic-ignition-advance-curves.21964/
Click to expand...
I can say this - the current Tri-Spark does not match this curve. Per the manual version 8:

"For example 29 Degrees BTDC for Norton or 38 Degrees BTDC for Triumph"

and

"To check the ignition timing with a strobe light, warm up the engine and aim your strobe light at the timing marks. You should see an image of the timing marks that advances as the revs are increased. At 3500 RPM the image will appear to stop advancing. Watch for the fully advanced timing marks to align at 3500 RPM and faster to confirm the timing is correctly set."

So, if you set full advance at 29 degrees, the ignition advances to 29 degrees at 3500 RPM and as far as I know stays there. I know it does up to at least 4000 but I don't rev engines to 7000 while timing to see if it falls off.

The graph you present may have been right at one time but is not now.
 
worntorn said:
Interesting, thanks for posting this.
The only ignition which appears to be always advancing with rpm is the Rita.
I've read that this is a big fault with Boyer but theres a nice flat there at the top end of the Boyer curve. Maybe the " always advancing with rpm" curve has been reconfigured with newer Boyer.
I'm not sure that the Trispark curve is exactly ideal at the top? Looks a bit out of control . Also, strange to see ignition timing pulling back with RPM, 5000-7000.
Click to expand...

The physics reality of a spinning magnet excited coil for the trigger will mean it means the trigger voltage continues to increase to a much higher RPM than we can spin the machine. That is called "asymptote" which means approaching forever but never getting there...Rita and analog boyer for sure as they both are working off the leading edge of the variable waveshape. The internals reactance of the trigger coil likely affects what that line it will attempt to meet, but it never gets there...
If another magnetic driven coil is used and works on the waveshape central crossover, than a new advance curve methodology needs to be implemented which is derived by math (computer) rather than magnetic physics.

marshg246 said:
it's not something I care about so I have not studied it.
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Very believable

marshg246 said:
as far as I know stays there
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Not believable- not true

marshg246 said:
Tri-Spark is tested to withstand 200volt spikes.
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I will have to evaluate the TS test to 200V? When the rita and boyer output transistor is spec/rated to 500v
A fallen off spark plug wire can easily make 400v reflected by the coil back to the box/circuit. Similarly a lost engine red ground will adversely affect the spark return path diverting to the clutch cable (teflon lined and isolated at the teflon/nylon cable end ????

Most of the time the ignition only needs about 6kv at idle (low cylinder pressure) the higher requirements are for open throttle (high pressure conditions)
 
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dynodave said:
Not believable- not true
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Interesting! you quote me saying "as far as I know stays there" and you say "not believable - not true".

It's really not nice to publicly call someone a liar! I'm perfectly happy to be told I'm wrong and why - happens often here - but I don't lie!
 
marshg246 said:
the ignition advances to 29 degrees at 3500 RPM and as far as I know stays there
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The timing functionality is the issue and is what I am talking about. The red highlighted part is not believable and totally incorrect as my explanation states.
I have no idea what you know or believe, which is not the issue at hand.

I'll add that if the TS advance, actually delay, is computer calculated, it is a matter of calculation of a time as a % of rotational time increment by picking a desired number out of a look up table. This result would be variable and gives the impression of a fixed ignition timing though a variable RPM.
A rotating magnet can cause an invisible physical advance similar to a mechanical advance. How ever a digital device can not magically make time travel and happen in the past before an event such as current crank position.
 
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A curve that should be there is the OEM AAU curve since it's the best one for an unmodified engine - full advance in by 3000 RPM. Back around '08, someone here posted a graph that contained all those ignitions Plus the OEM curve. In that graph, the Trispark was the closest to the OEM curve, which was why I selected it. It showed full advance at approx 3000 and staying there as the RPM climbed - as did the AAU. My reaction to seeing the graph in post #112 is that either the curve info is wrong or that TS changed their advance curve sometime in later versions. ASSUMING the graph is accurate, if I had to choose from one of the curves in Post 112 for my unmodified 850, I wouldn't! I'd put the points/AAU back in. ;)
 
MexicoMike said:
A curve that should be there is the OEM AAU curve since it's the best one for an unmodified engine - full advance in by 3000 RPM. Back around '08, someone here posted a graph that contained all those ignitions Plus the OEM curve. In that graph, the Trispark was the closest to the OEM curve, which was why I selected it. It showed full advance at approx 3000 and staying there as the RPM climbed - as did the AAU. My reaction to seeing the graph in post #112 is that either the curve info is wrong or that TS changed their advance curve sometime in later versions. ASSUMING the graph is accurate, if I had to choose from one of the curves in Post 112 for my unmodified 850, I wouldn't! I'd put the points/AAU back in. ;)
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Sort of agree the AAU function as I see it, is retarded to allow easy kick starting at about 5-7 deg BTDC. Once fired up it quickly ramps up to 28 is a good compromise for general purpose running. However the simplistic timing function is really geared up for WOT racing mode. While partial throttle cruising is under a significant retarded timing condition.
Looking at my chart done in Nov 1989 it starts to advance at 1200rpm(engine) and finishes at 2800rpm (engine) with an additional 26 deg
 
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MexicoMike said:
A curve that should be there is the OEM AAU curve since it's the best one for an unmodified engine - full advance in by 3000 RPM. Back around '08, someone here posted a graph that contained all those ignitions Plus the OEM curve. In that graph, the Trispark was the closest to the OEM curve, which was why I selected it. It showed full advance at approx 3000 and staying there as the RPM climbed - as did the AAU. My reaction to seeing the graph in post #112 is that either the curve info is wrong or that TS changed their advance curve sometime in later versions. ASSUMING the graph is accurate, if I had to choose from one of the curves in Post 112 for my unmodified 850, I wouldn't! I'd put the points/AAU back in. ;)
Click to expand...
From my time with a timing light, it's at full advance at 3500 and stays they to at least 4000. I think it actually reaches full advance more like 3300 but working alone it's hard to control the throttle, look a the (maybe inaccurate) tach, and watch the timing marks. I have not rev'ed higher than 4000-4500 so I don't know what it does. All I really care is that it reaches full advance and stops advancing - that's timed in my book.
 
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