Tri Spark woes

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I am starting to wonder? On a points/coil inductive discharge system, the commando little red ground at the head does two things, to accumuilate the electricity in the engine lump.

1. 12v points ground current return to the battery+ back out the battery - to ignition switch, kill switch, return to the coil again for the points.
2. Return path for the high side spark .

Once the points are removed and substituted with a normal EI, the only necessity for a return path is for the spark.
Make a mistake and loose the red ground wire at the head and does the little red wire on the TS take over receiving the spark return? ouch said the little electronic components...
 
dynodave said:
I am starting to wonder? On a points/coil inductive discharge system, the commando little red ground at the head does two things, to accumuilate the electricity in the engine lump.

1. 12v points ground current return to the battery+ back out the battery - to ignition switch, kill switch, return to the coil again for the points.
2. Return path for the high side spark .

Once the points are removed and substituted with a normal EI, the only necessity for a return path is for the spark.
Make a mistake and loose the red ground wire at the head and does the little red wire on the TS take over receiving the spark return? ouch said the little electronic components...
Click to expand...
No, Tri-Spark -> Kill Switch -> Negative Coil 1 || Positive Coil 1 -> Negative Coil 2 || Positive Coil 2 -> Red wire ground which ends up getting to the head if properly wired. If the engine ground is not there then the Tri-Spark red wire goes to the engine but there is no ground to the coil or battery or anything else. Of course, all speaking if wired as standard.
 
ludwig said:
"unless.."

Photo shows only the ground from frame to engine ( and ignition)
Although my frame is grounded, I do have a dedicated ground cable.
I am not stupid..
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No one implied that you are stupid. Your picture with no explanation is no different from several bikes I've fixed where there was no good ground.

In fact, on my first Norton, I used a braid like you did and then wondered why I had an intermittent ground - being used to Triumph's put me on that wrong path.
 
As I recall, the OEM harness red ground wire connects to the frame connection of the upper head steady, NOT to any bolt on the engine itself. There is also a connection to the frame for the OEM coils. NEITHER connects directly to the engine. To complete that circuit to the engine, multiple 'connections' between various bolts/plates occur before the ground is (hopefully) connected to the engine in an OEM pre Mark III engine.

As has been noted, Since the engine itself is the ground for the ignition primary and secondary. Any deficiency in that ground adversely affects everything related to the proper 'lighting' of the mixture in the cylinder AND to the life of any electronics that are involved. Points/AAU, of course, have no components to fail due to poor electrical connections. Electronic ignitions, on the other hand... ;)
 
MexicoMike said:
As I recall, the OEM harness red ground wire connects to the frame connection of the upper head steady, NOT to any bolt on the engine itself. There is also a connection to the frame for the OEM coils. NEITHER connects directly to the engine. To complete that circuit to the engine, multiple 'connections' between various bolts/plates occur before the ground is (hopefully) connected to the engine in an OEM pre Mark III engine.

As has been noted, Since the engine itself is the ground for the ignition primary and secondary. Any deficiency in that ground adversely affects everything related to the proper 'lighting' of the mixture in the cylinder AND to the life of any electronics that are involved. Points/AAU, of course, have no components to fail due to poor electrical connections. Electronic ignitions, on the other hand... ;)
Click to expand...
I have quite a few original wiring harnesses. There is a eyelet with 2 or 3 red wires that I have found on the timing side allen that attaches the head steady to the head. There is a female spade connector that connects to a male spade lug that is bolted to the coil mount at the condenser bracket to give the condensers ground, there is a eyelet that connects under the Zener to give it ground, and there is an eyelet that connects under the rectifier to give it ground. In all those cases but the first, unless the paint is scraped from the frame, there is no frame ground. The tail light and rear turn signals differ depending on the year. Once again, unless the paint is scraped from the frame at the various rear fender attachment points, there is no frame ground there either. The head light shell also has a ground and that ground has metal to metal contact all the way to the main frame, but providing ground through bearings is not a good idea.

There is no point in grounding the case of the coils - the case of the coils is isolated from both the primary and secondary windings.

Long story short, bikes will generally run when the engine ground is disconnected, and may run properly, until they don't. Poor grounds can cause problems that are difficult to diagnose.

Norton/Lucas must have understood this or they would not have wasted all the red wires providing ground to components I listed.
 
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MexicoMike said:
As I recall, the OEM harness red ground wire connects to the frame connection of the upper head steady, NOT to any bolt on the engine itself.
Click to expand...

The 'factory' position was the rear head steady stud:
Tri Spark woes





marshg246 said:
The head list [light] shell also has a ground and that ground has metal to metal contact all the way to the main frame, but providing ground through bearings is not a good idea.
Click to expand...

The shell connection isn't a 'ground'. It's there for the purpose of providing the front direction indicators with a return connection to the harness (red) via the headlamp shell.

"Metal to metal ground to the main frame" is also rather 'iffy' as the headlamp bracket tubes have O-rings at each end.
 
It has been established well enough for my own satisfaction that regardless of having everything else right, that running coils that don't match within the parameters of the TriSpark unit will burn it out. Apparently, again according to my own satisfaction, Pazon has a wider window of comfort. How much this has changed with later versions of TriSpark is unknown as I am pretty sure there is no data shared on this from the manufacturer. But I've been running a Pazon Sure-Fire for years without any trouble with exactly the same set up that burned out two TriSparks in a short period.
 
marshg246 said:
there is a eyelet that connects under the Zener to give it ground
Click to expand...

The eyelet is 5/16 and goes under the longer rear foot rest bolt and is held by the additional nut.

The original 71-74 harness' have IIRC 7 harness based red ground/return and are all interconnected.
The frame is NOT the + current carrying common return, though it's voltage level is zero.
 
No problem on the MK3 which has the starter earth lead from the engine. Also know an owner that has one fitted to an earlier Commando with Alton, again over 5 years trouble free service.
Mine was used with a podtronics without capacitor for the majority of 16,000 miles with no misfires.
 
L.A.B. said:
The 'factory' position was the rear head steady stud:
Tri Spark woes







The shell connection isn't a 'ground'. It's there for the purpose of providing the front direction indicators with a return connection to the harness (red) via the headlamp shell.

"Metal to metal ground to the main frame" is also rather 'iffy' as the headlamp bracket tubes have O-rings at each end.
Click to expand...
Glad to know the factory position, hopefully they removed paint where needed but I haven't seen that to be true. It's especially important with powder coating.

Was that also the position on a 750?
 
marshg246 said:
Long story short, bikes will generally run when the engine ground is disconnected, and may run properly, until they don't. Poor grounds can cause problems that are difficult to diagnose.
Click to expand...

Unfortunately without the red harness ground the engine tranny lump only gets grounded by the clutch cable. As you said the front end and headlight are not well grounded by the ball bearings. I know of two analog boyers that have died over this. It is also what I am suspecting from the red TS wire attached to the timing cover. I suspect that if the electronics were electrically OFF the engine things would be more reliable. That means a real wire back to the harness instead of a ring lug...in the case
Hey think of that... no ground wire AND a featherlight teflon lined clutch cable and teflon?nylon bush in the lever
 
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marshg246 said:
Was that also the position on a 750?
Click to expand...

Yes, as far as I know, although early (pre-71?) models had an engine 'ground' connection between the crankcase and the frame side stand mounting plate.
 
So, to sum this up, there are lots of potential grounds but unless there is a good engine ground to the central red wires, there will eventually be problems.

We can nit pick all day about which eyelet goes where, but with standard equipment, the engine, headlight shell, tail light, rectifier, Zener, condensers, and battery need a good ground. And, only the actual engine ground provides a reliable engine ground and that's only true if there is no paint/powder coat blocking the connection
 
I had and have a Trispark remote black box type on my Trident. It came with the bike. It would drop out whilst riding now and then. If you turned the bike off and then restarted it would be fine for a while. Finally quit in a corner and that was it for me I bought another after reading about early models having trouble. Six or so years now no worries.
Still have the old one. Can I send it back for examination, not as a warranty but to see if it has gone off and if so what it was. Long way to go and pay
for but you know always worth knowing not supposing.
 
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Hi Onder the black box unit on your Trident if it was turning itself off and then working ok after the ignition key was turned off and then worked ok when the Ignition was turned on again the most likely cause of this is interference from the coils. When there is electrical interference the black box turns off but will then reset when turned back on. Ensure that you have the correct suppressed plug leads and or mount the black box away from the coils
 
Box is minimum of 3 inches away. Caps correct resistive type. Both old and new box same distance. What is recommended distance I don' believe that is mentioned in the installation instructions.
Can I use Mu metal to shield the black box?
 
So far, no one has mentioned a failed current production (2016-) unit or a unit with test button (2013-) unless I missed it. I am recording all posts where there is info worth recording so I hope I haven't missed any.
 
marshg246 said:
So far, no one has mentioned a failed current production (2016-) unit or a unit with test button (2013-) unless I missed it. I am recording all posts where there is info worth recording so I hope I haven't missed any.
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Ahem.….
 
marshg246 said:
So far, no one has mentioned a failed current production (2016-) unit or a unit with test button (2013-) unless I missed it. I am recording all posts where there is info worth recording so I hope I haven't missed any.
Click to expand...

Tiz true for me, I switched to Pazon in 2012.
 
I have installed 2 in 2 different Nortons, the first one has now seen 10 years service, the second 7 years. As a dealer 10 more the last of which has been in service over 2 years, no failures. I have advised purchasers to install a ground loop that ties the circuits in the headlight to the engine, to the frame, to the taillight and the battery. I suggest that my customers break, clean and re-make all electrical connections, check battery and charging system.

In my service experience I have seen wiring harnesses that have been hacked into, spliced (and taped), that have wires which are cracked and brittle. I have also seen untouched original harnesses that are very close to the sins mentioned above; folks just as you won't live forever your original wiring harnesses, and components, won't either.

I wonder how many EI failures have root causes in "variable" resistance wiring harnesses?

Best.
 
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