Bonneville T140 1976 Electrical Wiring

Migsan

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Hi everyone
I am restoring a 1976 t140: The project had no electrical system just the wrong stator.
Got everything new (3 phase stator, coils, 9fl flasher, BB power box and electronic ignition).

POWER BOX
The 3 yellow wires from the power box were connected to the 3 wires of the stator.
Red wire connected to the battery positive.
Black wire to the battery negative with a fuse.

ELECTRONIC IGNITION
Black and white and black and yellow were connected to the wires of the ignition coil/condenser pack in the harness diagram respectively
Red wire to the first coil positive
black wire to the second coil negative
White wire to ignition coil white and yellow from the harness diagram.

COILS
1st coil positive to the battery. 1st coil negative to the 2nd coil positive.

FLASHER
B with the white from the battery

20200808_190943.jpg

I have this left hand switch20200808_191018.jpg witch I believe it's not the correct for this harness. Horn is working, rear turn signals are flashing really fast and sometimes when turned light the wrong side. Front turn signals not working
I believe the that part of the switch is correctly connected plus all colors match

20200808_191113.jpg

The upper part of the switch for high and low beam is not working. I have just the pilot light so far. I believe I need to connect it to the wires meant for the right side switch given that I think that this function was supposed to be on the right side. three wires blue/white blue/yellow and blue/red

20200808_191131.jpg

The right hand switch appears to be the original

20200808_191026.jpg
I connect the white and brown wire but I am left with 3 more wires I am not sure where to connect

20200808_191145.jpg
I got no spark. Rear presence light is on but stop switch is not working.

I am starting to get frustrated on my own so would be really grateful if someone could help.
Thanks
Miguel
 

Migsan

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Forgot to mention the light switch was connected the following way
Blue and yellow wire that show on the harness wiring diagram is on #8
Brown and white #3
Brown and green #4
seems to be working ok clocks, oil warning light and turn warning light working

Cheers
 

grandpaul

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My mind has gotten "soft" not working on these bikes for almost 2 years now, and I especially dislike the newer style Lucas switches that you have. (Most of the ones I've messed with DID NOT MATCH CORRECTLY!

I'd need to draw it all out on paper, one wire at a time to see where your issues lie, but the first one I see is the two EI trigger wires should run directly to the stator behind the little round cover on the timing side of the engine, just above the shifter. NO CONDENSERS.

What brand/model EI unit, and is the system set up for positive ground? That all matters, and there should be a direct ground to one of the 4 coil terminals, depending on polarity of your system ground.

Let's start there...

Oh, yes, you need to rule out a dodgy keyswitch internal connection, and kill switch connection. Try hot-wiring it by bypassing both and simply running the EI power lead to the appropriate battery terminal for your polarity... Also double-check the trigger wire connections at the ignition stator. (and if you had condensers still wired in, they'd be screwing with you now)
 

Migsan

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Hi Grandpaul
Thank you for replying!
It's positive earth! boyer bransden kit 00052
I have no condensers. I connected to the wires that were supposed to go on the condensers because they have the same color of the ones that come out of the contact points according the the harness diagram
So I connected the black and yellow wire from the EI to the black and yellow connectors that come out of the harness described has condenser pack and ignition coil, Did the same for the black and white wire from the EI.
These are the diagrams that came with the kit and the powerbox.

20200808_192429.jpg20200809_101646(1).jpg




Oh, yes, you need to rule out a dodgy keyswitch internal connection, and kill switch connection. Try hot-wiring it by bypassing both
[/QUOTE]

You mean joining the 3 wires together right white, brown and brown and white?
 

Migsan

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Hi Grandpaul
Thank you for replying!
It's positive earth! boyer bransden kit 00052
I have no condensers. I connected to the wires that were supposed to go on the condensers because they have the same color of the ones that come out of the contact points according the the harness diagram
So I connected the black and yellow wire from the EI to the black and yellow connectors that come out of the harness described has condenser pack and ignition coil, Did the same for the black and white wire from the EI.
These are the diagrams that came with the kit and the powerbox.

View attachment 48099View attachment 48100




Oh, yes, you need to rule out a dodgy keyswitch internal connection, and kill switch connection. Try hot-wiring it by bypassing both

You mean joining the 3 wires together right white, brown and brown and white?
[/QUOTE]
Hi everyone
Just did like Grandpaul said.
With the voltmeter checked ignition switch working fine.
On the right hand side kill switch is working to between white and yellow and white and blue. White and brown are always on.
My question should I connect the white and yellow and white and blue from the right hand switch to the double white and white and yellow that says LH switch on the harness diagram?
Cheers
 

Rudie

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Very quickly or @LannyDaise will think I have abandoned him ...
new
BB
electronic ignition

ELECTRONIC IGNITION
Black and white and black and yellow were connected to the wires of the ignition coil/condenser pack in the harness diagram respectively
Given you have the BB fitting instructions, where do they tell you to connect the Black/Yellow and Black/White wires to the coils?

I have this left hand switch



believe it's not the correct for this harness.
You are looking at the wrong 1976 parts book. The one dated February 1976 has numerous misprints, one of which is showing the left hand handlebar switch cluster used before 1976. In reality, it is electrically-impossible to use the two handlebar switch clusters shown in the February 1976 parts book together - some functions would be missing, others would be duplicated.

Use the parts book published in August 1976 - while that one does not show it, the copy I have says, "Revised August 1976"; it is not completely free of errors but it has far fewer than the February 1976 one.

Front turn signals not working
Usual fault is they are bolted to well painted/powder coated headlamp brackets. If so, good paint or powder coating does not conduct electricity, the turn signals do not have an electrical return to battery +ve. I make up short lengths of wire to fit between each turn signal stem securing nut and an existing Red wires "Sleeve Connector" inside the headlamp shell. If that means you require Sleeve Connectors that take more than two bullet terminals in each end, Autosparks sells Three Way Sleeve Connector and Four Way Sleeve Connector.

upper part of the switch for high and low beam is not working.
I believe I need to connect it to the wires meant for the right side switch given that I think that this function was supposed to be on the right side. three wires blue/white blue/yellow and blue/red
You are mistaken, in part because you are using the wrong parts book but also because you are using the wrong Wassell "Trust Lucas" :ROFLMAO: wiring diagram - the one in your post is for pre-'76 handlebar switch clusters (and even then it has several mistakes ...):-

The right hand switch appears to be the original
. No (it has "L F HARRIS" where originals had "LUCAS" cast - LFH is one of the big British parts wholesalers, they made at least one batch of those switch clusters before Sparx).

. In addition, someone has cut off the AMP pins connector that your new harness uses for handlebar switch cluster connection - aside, no bad thing as AMP connectors were always troublesome. However, you need proper connectors, not those mickey mouse red or blue insulated bodger's terminals; as I have highlighted Autosparks already, Small Bullet Crimp Set with no Tools, Bullet Crimp Tool and Bullet Closing Tool.

I connect the white and brown wire but I am left with 3 more wires I am not sure where to connect
. Plain Brown wire ends should also be at the (brighter) stop filament connector in the rear lamp and at one terminal of the switch by the rear brake lever; there should be a short plain Brown wire from the right-hand switch cluster to the front brake switch that fits inside the master cylinder mounting. So the plain Brown wire from the switch cluster inside the headlamp shell should be connected to the plain Brown wire out of the main loom inside the headlamp shell.

. Then you need to look inside the switch:-

.. One of either plain White or White/Blue also has a short wire from the switch cluster to the front brake switch; whichever of White or White/Blue has that short wire connected, the White or White/Blue wire from the switch cluster inside the headlamp shell must be connected into a White wires sleeve connector inside the headlamp shell - White wires are 'live' when the ignition switch is on, that supplies the front brake switch, pulling the front brake lever should actuate the switch inside the master cylinder mounting, the switch makes the Brown wire to the rear lamp stop filament 'live'.

.. One of either plain White or White/Blue also connects to the kill switch (red lever); if it is not the same as the wire that supplies the front brake switch, this wire also must be connected into a White wires sleeve connector inside the headlamp shell. The White/Yellow wire from the switch cluster inside the headlamp shell must be connected to the White/Yellow wire out of the main loom inside the headlamp shell; you have posted the other end of that White/Yellow wire is connected to the BB e.i. White wire.

.. The White/Red wire was originally for the T160 electric starter. I advise cutting off the existing terminal, crimping on one of your new bullet terminals and either connecting it into the Blue/White wires sleeve connector inside the headlamp shell - that will turn the connected button in the switch cluster into a headlamp flash button - or simply pushing the new bullet terminal into a single sleeve Connector - that will insulate the White/Red if the handlebar cluster button is pressed accidentally.

. Returning to your left hand switch cluster, the AMP pin connector on the end of "three wires blue/white blue/yellow and blue/red" should connect to the main loom; from the main loom, Blue/Red and Blue/White wires should connect to headlamp dip and headlamp main respectively, Blue/Yellow should connect to terminal #8 of the 3-position lever switch in the top of the headlamp shell.

no spark.
Apart from the Black/Yellow and Black/White wires connected incorrectly to the coils, although your BB e.i. White wire is connected to a White/Yellow under the seat, the other end of the White/Yellow inside the headlamp shell is not connected to the handlebar switch cluster White/Yellow and kill switch, and whatever supplies the kill switch (handlebar switch cluster plain White or White/Blue) is not connected to the White wires from the ignition switch.

stop switch is not working.
Stop (brighter) filament in the rear lamp bulb should be contacting a plain Brown wire terminal, the plain Brown wire should go through the main loom to the switch by the rear brake lever and there should be an end out of the main loom inside the headlamp shell; that end should connect to the plain Brown wire out of the handlebar switch cluster, where it should also connect to the switch inside the front master cylinder mounting.

Both switches should be supplied by a plain White wire (possibly White/Blue at the front?); this wire out of the handlebar switch cluster connected into the White wires sleeve connector inside the headlamp shell, the switches will be 'live' when the ignition switch is on.

light switch was connected
Blue and yellow wire that show on the harness wiring diagram is on #8
Brown and white #3
Brown and green #4
seems to be working ok clocks, oil warning light and turn warning light working
If, by "light switch" you mean the 3-positing lever switch in the top of the headlamp shell, "clocks, oil warning light and turn warning light" are not supplied by that switch.

"Brown and white #3 | Brown and green #4" is only correct if your bike has the corresponding light switch, you need to remove the switch from the headlamp shell and look for a five figure number - either "34419", "35710" or "31788" - it will be either stamped into the chromed top of the switch or moulded on the black plastic casing:-

. If it is 34419, "Brown and white #3 | Brown and green #4" are correct, as is "Blue and yellow ... #8"; however, there should be a plain White wire connect to #7 or the headlamp will not work ... not only is the "Trust Lucas" :ROFLMAO: wiring diagram wrong for your bike, it is also wrong for the earlier bikes it was intended for.

. If the switch is "35710" or "31788", it must be connected differently:-

.. Blue/Yellow still to terminal #8;

.. Brown/Green to terminal #7;

.. Brown/White to terminal #4;

.. no White wire connected.
 

Migsan

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Hi Rudie
Thank you for all the info!

Given you have the BB fitting instructions, where do they tell you to connect the Black/Yellow and Black/White wires to the coils?
No I didn't connect them to the coils what I meant was to the wires on the harness diagram that say ignition coil with the correspondent color. The coils were wired like on the diagram that I showed with the power box.
red wire BB on the first coil positive along with battery positive. First coil negative to second coil positive. BB black wire to the second coil negative.
B/Y wire from the BB electronic ignition connected to the B/Y connectors were the coils and condenser would be and B/W BB electronic ignition to the B/W connectors were the coils and condenser would be (according to the harness diagram). the White wire from the BB I connected to the W/Y wire that says ignition coil again from the harness diagram.

Usual fault is they are bolted to well painted/powder coated headlamp brackets. If so, good paint or powder coating does not conduct electricity, the turn signals do not have an electrical return to battery +ve. I make up short lengths of wire to fit between each turn signal stem securing nut and an existing Red wires "Sleeve Connector" inside the headlamp shell. If that means you require Sleeve Connectors that take more than two bullet terminals in each end, Autosparks sells Three Way Sleeve Connector and Four Way Sleeve Connector.
Worked really well with the ground wire but the signals are still crossed and the frequency of the turn signals still very high. Was working on the correct side previously and I rechecked the wires and they seemed to be correct.

Stop (brighter) filament in the rear lamp bulb should be contacting a plain Brown wire terminal, the plain Brown wire should go through the main loom to the switch by the rear brake lever and there should be an end out of the main loom inside the headlamp shell; that end should connect to the plain Brown wire out of the handlebar switch cluster, where it should also connect to the switch inside the front master cylinder mounting.
Still not working just the presence light. I don't have any of the small wire connections on the R/H switch you mention. Are you talking about that hydraulic front brake switch because I can´t find it not even in the revised replacement parts book you provided.

The White/Red wire was originally for the T160 electric starter. I advise cutting off the existing terminal, crimping on one of your new bullet terminals and either connecting it into the Blue/White wires sleeve connector inside the headlamp shell - that will turn the connected button in the switch cluster into a headlamp flash button - or simply pushing the new bullet terminal into a single sleeve Connector - that will insulate the White/Red if the handlebar cluster button is pressed accidentally.
Tried to connect to the blue and white but when I present the button on the R/H switch it burned the fuse from the battery negative. But the headlight is not working anyway so could be due to some other wrong connection.

If it is 34419, "Brown and white #3 | Brown and green #4" are correct, as is "Blue and yellow ... #8"; however, there should be a plain White wire connect to #7 or the headlamp will not work ... not only is the "Trust Lucas" :ROFLMAO: wiring diagram wrong for your bike, it is also wrong for the earlier bikes it was intended for
It's the 34419. I had a spare white wire that I had connected to the white and red but when I hot wire to the 7# still no head light :(

White wire is connected to a White/Yellow under the seat, the other end of the White/Yellow inside the headlamp shell is not connected to the handlebar switch cluster White/Yellow and kill switch, and whatever supplies the kill switch (handlebar switch cluster plain White or White/Blue) is not connected to the White wires from the ignition switch.
Tested the continuity with the voltmeter and the kill switch seems to be working fine between the white/yellow R/H switch wire and the white/blue R/H switch, they are connected to the white/yellow and white wires from the harness in the same order.

Yet I can only get a spark when I check the continuity with the voltmeter between the black and white wire or black and yellow wire the I mentioned previously (where the ignition coils used to be connected on the wire diagram) and the engine. If I disconnect the same wires from the BB electronic ignition and tested again with either end (harness or EI black/white or black/yellow) the spark is gone.
I confirmed the ground wires and they seem to be passing in to the engine correctly when tested despite the powder coat through the bolts. I got the one in the headlamp, the one on the engine head, another I fitted under the coils metal tray and the last one over mudguard stay under the seat.

Returning to your left hand switch cluster, the AMP pin connector on the end of "three wires blue/white blue/yellow and blue/red" should connect to the main loom; from the main loom, Blue/Red and Blue/White wires should connect to headlamp dip and headlamp main respectively, Blue/Yellow should connect to terminal #8 of the 3-position lever switch in the top of the headlamp shell.
Connected the blue/white and blue yellow like you described. Already had the blue/yellow on the 8# position but the there is still another connection available on the main loom wich I used to connect the remaining blue /yellow that comes from the L/H switch cluster. Still no head light. The filaments inside the bulb seem to be fine. On the harness diagram the three wires come described like R/H switch o_O:ROFLMAO:

Thank you very much!
Cheers
Miguel
 

Rudie

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Several
coils were wired like on the diagram that I showed with the power box.
White wire from the BB I connected to the W/Y wire that says ignition coil again from the harness diagram.
(y)

To be clear about "W/Y wire that says ignition coil again from the harness diagram", there are two female spade terminals, originally one to each coil negative terminal with points; your BB e.i. White wire is connected to one W/Y female spade and the other is insulated?

Front turn signals
Worked really well with the ground wire but the signals are still crossed and the frequency of the turn signals still very high.
"signals ... still crossed" is a connection fault.

With two turn signals working together "frequency of the turn signals still very high" is likely a faulty relay and/or incorrect bulb resistance:-

. Original relay was called "8FL"; however, as usual, Wassell have screwed up and made life difficult for everyone by making two versions in different physical sizes ... If you have either one of these or an eBay cheapie, I advise ditching it for a Lucas 9FL, it fits in the same mounting bracket as an 8FL but is ime more robust.

. 12V turn signal bulbs must have a resistance of approximately 7 Ohms each.

I don't have any of the small wire connections on the R/H switch you mention.
Your image showed that; that is why I advised buying some useful terminals and a crimping tool.

What would have made my previous post clearer was:-

P2280504.JPG

... which is an unused Harris switch cluster:-

. Front brake switch is top left of the image.

. White/Blue wire is supply to both the kill switch and the front brake switch; as you have posted this is the same on the switch on your bike, where your "Trust Lucas" 'wiring diagram' :ROFLMAO: says "L/H switch", inside the headlamp shell, connect:-

.. the other end of the switch White/Yellow to the main loom White/Yellow;

.. the other end of the switch White/Blue wire into the White wires - this will be a Sleeve Connector with White wires, including one from the ignition switch.

. Only connect the other end of the switch Brown wire to the main harness Brown wire if your switch cluster has the front brake switch shown, otherwise insulate the end of the switch Brown wire inside the headlamp shell.

. If the switch cluster on your bike is wired the same as my image, the plain White wire is connected to the White/Red wire at one of the black push-buttons:-

.. If you do not intend to use the push-button as an additional headlamp flash button, I advise simply cutting the terminals off the ends of both wires inside the headlamp shell.

.. Otoh, if you do with to use the push-button as an additional headlamp flash button, inside the headlamp shell, connect the switch White/Red into the headlamp main Sleeve Connector (Blue/White wires) and the switch White wire into a Sleeve Connector with White wires including one from the ignition switch.

Finally here, the bullet terminals shown in my image are available from Vehicle Wiring Products - W Crimp Type 4.7mm Bullet and a matching crimping tool; for information, they fit the standard bullet female connectors - Autosparks "Sleeve Connectors", VWP calls them "Snap Connectors".

[Stop lamp] Still not working
Even if your right-hand handlebar switch cluster does not have the front brake switch, the stop lamp should still work from the switch by the rear brake lever, shown as "Stop Switch" at the right-hand end end of that "Trust Lucas" 'wiring diagram'.

front brake switch
I can´t find it not even in the revised replacement parts book
Not shown in any parts book, probably because it was not available separately from the switch cluster.

Tried to connect to the blue and white but when I present the button on the R/H switch it burned the fuse from the battery negative. But the headlight is not working anyway so could be due to some other wrong connection.
34419. I had a spare white wire that I had connected to the white and red but when I hot wire to the 7# still no head light
This is :confused:

White wires are (should) be 'live' only when the ignition switch is on, the ignition switch connects Brown/Blue from battery -ve to the White wires:-

. Your bike's "headlight is not working" because, although you have connected the left-hand handlebar dipswitch Blue/Yellow supply wire to the 34419 switch terminal #8, terminal #8 is supplied from terminal #7 when the 34419 lever is fully to the right, and you have not connected anything to terminal #7 because the crappy Wassel Lucas 'wiring diagram' you are using does not say to connect anything to terminal #7. :rolleyes:

. If you connect random "spare" wires and expect electrics to work, you will be disappointed regularly. From above, 34419 terminal #7 requires a White wire specifically connected electrically to the ignition switch, probably through a multi-way Sleeve/Snap Connector inside the headlamp shell.

. In addition to the ridiculous Wassel Lucas 'wiring diagram' you are using, I suggest the one in the Triumph workshop manual covering your bike, the correct diagram is on manual page H22, .pdf page 191.

. Neither of the diagrams show the White/Red wire from the right-hand handlebar switch cluster, because White/Red is the Lucas colour code for electric-start and twins never had an electric-start until the 1980's. The reason the switch clusters have a White/Red in reality is they were originally for the T160, which does have an electric-start.

. If you are confused by my suggestion to use the White/Red wire from your bike's right-hand switch cluster as a headlamp flash button, forget it; verify with the Ohms setting on your multi-meter that the White wire into switch cluster supplies only the button with the White/Red wire; if so, simply cut off the existing terminals from the switch cluster White and White/Red wires.

Tested the continuity with the voltmeter and the kill switch seems to be working fine between the white/yellow R/H switch wire and the white/blue R/H switch, they are connected to the white/yellow and white wires from the harness in the same order.
Yet I can only get a spark when I check the continuity with the voltmeter between the black and white wire or black and yellow wire
BB (and clones like Pazon, Wassell/Vape and Sparx) e.i. for twins and singles incorporate a major testing :y40: ... after the "Transistor Box" is powered up, unless the Box electronics 'detect engine movement' (rising and falling Voltages from the "Stator" through the Black/White and Black/Yellow wires) within a few seconds, the Box switches off the coil(s) supply (the Black wire; the Box switches it back on when it 'detects engine movement') ... Bransden alleges this is to stop the coil(s) draining the battery but ime it is just a pita, and his e.i. for triples do not have the 'feature' (nor do Lucas Rita nor any of the Tri-Spark e.i. ... :whistle2:).

The way to test for HT sparks is: connect a plug to one of the HT leads and lay it on the cylinder head, ensuring the plug has a good earth; with the Transistor Box and coils powered (connected to the battery either directly or through the switches), touch either the Box Black/White or Black/Yellow wire to a part of the bike, you should see a stream of HT sparks at the plug.

I confirmed the ground wires and they seem to be passing in to the engine correctly when tested despite the powder coat through the bolts. I got the one in the headlamp, the one on the engine head, another I fitted under the coils metal tray and the last one over mudguard stay under the seat.
This is a mistake, by-and-large British bikes - particularly one as new as 1976 - do not have "ground wires". Before '79, the network of Red wires in a standard British bike harness are the primary electrical connection between components and the battery +ve terminal, they avoid the electrics having to rely on bits of bike for part of the circuits. The Red wire ends with (mostly) ring terminals were for attaching specifically to the mountings of components that 'earthed' through their mounting - e.g. rectifier, Zener, original bulb holders. As you have replaced the points with e.i. and you (should) have attached wires to the turn signals mountings, the only components that still 'earth' through their mountings but do not have Red wires attached are the oil pressure switch and the spark plugs, is why there is a Red wire "on the engine head".

"the one in the headlamp" attaches either to the headlamp bulb holder or a loop rivetted to the headlamp shell bottom front? If the latter and the headlamp shell is rusty under the loop, it will not work as an electrical connection. :(

"under the coils metal tray" was probably the one for the condensers, originally beside each ignition coil.

However, never anything electrical on the "mudguard stay under the seat" so this is a mistake.

Connected the blue/white and blue yellow like you described. Already had the blue/yellow on the 8# position but the there is still another connection available on the main loom wich I used to connect the remaining blue /yellow that comes from the L/H switch cluster.
This is :confused: again. Look at the Triumph workshop manual wiring diagram, follow the Blue/Yellow ("UY") line from the lights switch "(OFF SIDE HEAD)" to "DIP SW.", there is not (and cannot be) "another connection available on the main loom" - either you have mistaken the wire colours or, if the main loom your are using is a Wassell Lucas one, regrettably they are poor quality, you will need your meter to ascertain which are the correct Blue/Yellow wires to connect lights switch terminal #8 with the dipswitch. :(

On the harness diagram the three wires come described like R/H switch
The Wassell Lucas diagram is not for your bike, it is for a '73-'75 T140, TR7 or T120, with the earlier handlebar switch clusters - look basically-similar to your bike's right-hand switch cluster but have a short black lever instead of your bike's red lever, right lever is the dipswitch, left lever is for turn signals; they connect to the main loom with bullets and sleeve/snap connectors, not AMP pin connectors.
 

grandpaul

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I love Rudy's answers, always in-depth. After the third one, though, may as well just read the (CORRECT) wiring diagram and transcribe what you are looking at, one wire at a time!

That would avoid any shadow of a doubt...

Carry on!
 

Migsan

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Hi everyone!
Thank you for your time Rudie. I really appreciate your patience. It's the first bike I am working and I am learning everything from scratch.

To be clear about "W/Y wire that says ignition coil again from the harness diagram", there are two female spade terminals, originally one to each coil negative terminal with points; your BB e.i. White wire is connected to one W/Y female spade and the other is insulated?
It's female spade connector and I wraped it in insulating tape.

"signals ... still crossed" is a connection fault.

With two turn signals working together "frequency of the turn signals still very high" is likely a faulty relay and/or incorrect bulb resistance:-

. Original relay was called "8FL"; however, as usual, Wassell have screwed up and made life difficult for everyone by making two versions in different physical sizes ... If you have either one of these or an eBay cheapie, I advise ditching it for a Lucas 9FL, it fits in the same mounting bracket as an 8FL but is ime more robust.

I got the 9FL that you recommended on a previous thread.
I checked the bulbs and you are right they are 23 W and they should be 21 W according to the manual. I will have to recheck everything maybe the sides are wrong if the instructions of the harness are useless. Got green and white for L/H signal and green red for the R/H turn signal.

20200810_213314.jpg20200810_213418.jpg
It seems someone got to mine first
So that little plastic bit goes inside the other half of the switch where the master cylinder connects?
I understand these are gonna be hard to find separately. Is it possible to create a similar way to make it work? pictures of the part in place would be of great help!

.. the other end of the switch White/Yellow to the main loom White/Yellow;
Done!

.. the other end of the switch White/Blue wire into the White wires - this will be a Sleeve Connector with White wires, including one from the ignition switch.
I already ordered the bullet connectors and the double sleeve connectors.


Even if your right-hand handlebar switch cluster does not have the front brake switch, the stop lamp should still work from the switch by the rear brake lever, shown as "Stop Switch" at the right-hand end end of that "Trust Lucas" 'wiring diagram'.
Tested the rear switch it´s ok and the two wires brown and white are also ok for continuity.

The way to test for HT sparks is: connect a plug to one of the HT leads and lay it on the cylinder head, ensuring the plug has a good earth; with the Transistor Box and coils powered (connected to the battery either directly or through the switches), touch either the Box Black/White or Black/Yellow wire to a part of the bike, you should see a stream of HT sparks at the plug.
I checked and it does spark. Does that mean that those connections are correct ?(meaning EI black/white and black/yellow + EI white to white yellow)

This is a mistake, by-and-large British bikes - particularly one as new as 1976 - do not have "ground wires". Before '79, the network of Red wires in a standard British bike harness are the primary electrical connection between components and the battery +ve terminal, they avoid the electrics having to rely on bits of bike for part of the circuits. The Red wire ends with (mostly) ring terminals were for attaching specifically to the mountings of components that 'earthed' through their mounting - e.g. rectifier, Zener, original bulb holders. As you have replaced the points with e.i. and you (should) have attached wires to the turn signals mountings, the only components that still 'earth' through their mountings but do not have Red wires attached are the oil pressure switch and the spark plugs, is why there is a Red wire "on the engine head".

"the one in the headlamp" attaches either to the headlamp bulb holder or a loop rivetted to the headlamp shell bottom front? If the latter and the headlamp shell is rusty under the loop, it will not work as an electrical connection. :(

"under the coils metal tray" was probably the one for the condensers, originally beside each ignition coil.

However, never anything electrical on the "mudguard stay under the seat" so this is a mistake.
So how would you suggest to connect the red wires described on the trust Lucas like "earth"? I connected it to the mudguard stay because I saw some pictures on other T140 :(

Thank´s
Cheers
Miguel
 

Rudie

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I got the 9FL that you recommended on a previous thread.
I checked the bulbs and you are right they are 23 W and they should be 21 W according to the manual.
Should not make a difference to a 9FL, Lucas supplied 8FL to work turn signals and 9FL to car, van and lorry makers to work turn signals in 'hazard' mode so I would not have expected the difference between European 21W resistance and US 23W resistance to be an issue?

Got green and white for L/H signal and green red for the R/H turn signal.
maybe the sides are wrong
:rolleyes: They are wrong, should be the other way around. That said, I notice whoever drew the wiring diagram in the Triumph workshop manual managed to miss out any colours indication at all for the turn signals wires; however, the colours are shown in the diagram on the previous manual page ...

[Front brake switch]
I understand these are gonna be hard to find separately. Is it possible to create a similar way to make it work? pictures of the part in place would be of great help!
I would not bother, ime they are useless devices even when present. I have never understood why Triumph wasted six years with this switch - when Triumph first fitted the disc brake, Norton had had a master cylinder mounting for two years that incorporated a proper pressure switch; when the Co-op finally admitted defeat for '79, the pressure switch and brass T-piece were off-the-shelf automotive parts.

My preferences for a front brake switch are either the Goodridge BL775-03C hydraulic switch - fits in place of the standard master cylinder banjo bolt - or the pressure switch and T-piece Triumph used '79-on; as I say, they are off-the-shelf multi-vehicle parts, or Triumph's part numbers are 60-7155 and 60-7176; however, both have (y) and (n):-

. Goodridge bolt: (y) easy to fit, (n) ugly.

. '79-on Triumph parts: not too hard to fit - T screws to the end of the rubber hose poking through the lower yoke stanchion clamp, switch fits on top, all just behind the headlamp shell; (n) special piece of hose is required between the T and either where the standard top hose pokes through the top yoke, or directly to the master cylinder; swiped from another forum:-



P5100670.JPG

[Right-hand switch cluster]
You might want to consider a spray electrical contact cleaner to remove rust and other corrosion?

test for HT sparks
it does spark. Does that mean that those connections are correct ?(meaning EI black/white and black/yellow + EI white to white yellow)
(y)


So how would you suggest to connect the red wires described on the trust Lucas like "earth"?
The two upper left are from "Speedo Bulb" and "Tacho Bulb".

The one top right is from the rear lamp.

Bottom right:-

. there are not two "Engine Earth"; one is, the one between "Zener" and "Rectifier" is likely to be the one that attached to the airbox between those two components to 'earth' them;

. leaving the one marked "Rectifier Earth" as the one for the condensers.

Because "Stator", "Rectifier" and "Rectifier Earth" are crossed off, I am guessing you have replaced Rectifier and Zener with a combined regulator/rectifier, and connected the alternator Stator to it directly?

Attach the Zener-Rectifier and condensers Red wires where they were originally intended if you wish; if/as the components are not present/in use, attaching the Red wires will not serve any useful purpose except to keep them tidy.
 

Migsan

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Hi Everyone
Thanks for all the useful information Rudie

I will change the wire on the turn signals today!

The banjo bolt for the front brake switch seems like a practical solution. Do you know whats the correct thread? Also how do I connect the switch? should I weld the wires (white and blue and brown) like the image you showed me?


ecause "Stator", "Rectifier" and "Rectifier Earth" are crossed off, I am guessing you have replaced Rectifier and Zener with a combined regulator/rectifier, and connected the alternator Stator to it directly?
yes I connected the 3 wires from the 3 phase stator to the 3 yellow wires from the power box and the remaining two directly to the battery with a fuse on the negative.
So if you say my connections on the electronic ignition are correct, shouldn't I have spark when with both the kill switch and ignition switch on I kick start the engine?

Cheers
Miguel
 

Rudie

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banjo bolt for the front brake switch seems like a practical solution. Do you know whats the correct thread?
3/8"UNF. Goodridge make several of those bolts with different threads, the part number I posted is for the 3/8"UNF one.

Be aware there are other suppliers using the Goodridge part number; e.g. I just clicked on one on eBay supplied from China, you couldn't be sure what the thread would be. :(

how do I connect the switch?
If the banjo bolt's wires are long enough to be threaded into the headlamp shell, connect one wire to the plain Brown wire, the other wire into an existing White wires Sleeve/snap Connector.

To keep the wires tidy, consider a length of black heatshrink sleeving slid over the brake hose and the wires, shrunk around hose and wires when everything's assembled and tested?

If the banjo bolt's wires aren't long enough to be threaded into the headlamp shell, you'll need to extend them so they can be connected as above. About the most discreet and waterproof connectors are this male with this female. The heatshink sleeving would cover these too.
 

Migsan

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Thanks Rudie
Almost solved all the issues with the wiring.
Will order the switch from the link you posted!

Still need to understand why I have no spark when I kick-start but will get there eventually.
Cheers
 

Rudie

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Still need to understand why I have no spark when I kick-start
test for HT sparks
it does spark.
Repeat the "test for HT sparks" in my post #8. If it still sparks in that test, but not when the Stator is connected to the Transistor Box with the Black/White and Black/Yellow wires, the fault/s is/are in the Stator or those wires. What is the resistance measured: first between the ends of the Black/White and Black/Yellow wires to the Stator by the Transistor Box; then between the ends of the Black/White and Black/Yellow wires at the Stator itself?
 

Migsan

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Repeat the "test for HT sparks" in my post #8. If it still sparks in that test, but not when the Stator is connected to the Transistor Box with the Black/White and Black/Yellow wires, the fault/s is/are in the Stator or those wires. What is the resistance measured: first between the ends of the Black/White and Black/Yellow wires to the Stator by the Transistor Box; then between the ends of the Black/White and Black/Yellow wires at the Stator itself?
Hi Rudie
All good everything working fine, even the red and white for the flasher :)(y)
Tested again today and I have spark. Just waiting for the switch to arrive and the project will be completeBBEER
Thanks again for all the help, everything was just like you described!
Cheers
 
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