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#850570 06/03/21 1:07 pm
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Kevin E Offline OP
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Hi all,

I am about to start making up the new wiring harness for my 1966 A65 Lightning.

I thought I would share my details, along with my electrical schematics/wiring diagram in the hope that it may be of some help to other members of this forum.

I work as an electrical controls engineer and have been doing this for some years now. My duties include the design and drawing of electrical circuits for the automated production machinery that is built by the company I work for. The electrical controls systems are pretty complex and usually consist of dozens to hundreds of pages.

The A65 system is pretty simple and I have drawn it up, along with my modifications, in a way that keeps everything somewhere close to how it is laid out on the bike. Not exactly to scale, but something that makes sense and is easy to follow.

I like to keep the load off things like handlebar switches, so I have used a couple of relays. One is a changeover relay for the headlight main and dip beams and the other is a simple on/off for the horn. I have also fitted a neat little 4 way fuse box, with continental spade fuses to give a little added short circuit and overload protection to the equipment.

I am using a 3 phase alternator with a Podtronics regulator and a Boyer Mk3 Ignition system. The battery is a Motobatt MB9U AGM type.

If this is of any help to anyone I can let you have this wiring diagram in AutoCad .dwg or .pdf format.

Cheers,

Kev E

A65 Custom Wiring.JPG
Last edited by Kevin E; 06/03/21 1:08 pm.
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Kevin E #850571 06/03/21 1:30 pm
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That's brilliant - thanks very much Kev!


'67 A65 Thunderbolt
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RobJP #850597 06/03/21 6:45 pm
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Kevin E Offline OP
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Originally Posted by RobJP
That's brilliant - thanks very much Kev!

You're very welcome Rob, it's nice to give something back for all the help I have received from the BSA owners on this site.

The detail isn't a lot of use on the uploaded image but if you want the pdf, or .dwg file just drop me a message with your email address and I can send it to you. Same goes for anyone who would like a copy.

I will post some pics of the bits and pieces mounted and connected up as I get the job moving along.

Cheers, Kev E

Kevin E #850745 06/05/21 8:07 am
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Kev, I don't have a need for this diagram, but I thought I'd take a look just out of interest. But I can't read the labels on the posted JPG. When I blow it up, they just get fuzzy. I think my email address is in my profile.

Although the schematic doesn't show this, I'm particularly curious about where you're mounting the fuse box and relays.


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Mark Z #850746 06/05/21 8:14 am
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Kevin E Offline OP
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Originally Posted by Mark Z
Kev, I don't have a need for this diagram, but I thought I'd take a look just out of interest. But I can't read the labels on the posted JPG. When I blow it up, they just get fuzzy. I think my email address is in my profile.

Although the schematic doesn't show this, I'm particularly curious about where you're mounting the fuse box and relays.

Hi Mark,

The image I posted on here is actually a screenshot using the windows snipping tool. This forum won’t allow you to post pdf files, so I had to do it this way. I have a couple of pdf files of the schematics. One for the whole kit and one that shows the detail in the headlamp section. I am away from home right now but when I return I will make some more detailed images to post here.

The fuse box I mounted on a bracket underneath the battery and the relays are inside the headlamp shell.

Cheers,

Kev E

Kevin E #850749 06/05/21 8:52 am
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Originally Posted by Kevin E
I am away from home right now but when I return I will make some more detailed images to post here.

The fuse box I mounted on a bracket underneath the battery and the relays are inside the headlamp shell.

Cheers,

Kev E

Ok, no rush; it's purely academic for me.

Relays inside the headlamp shell, they must be quite small!


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Mark Z #850753 06/05/21 10:05 am
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Kevin E Offline OP
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Originally Posted by Mark Z
Originally Posted by Kevin E
I am away from home right now but when I return I will make some more detailed images to post here.

The fuse box I mounted on a bracket underneath the battery and the relays are inside the headlamp shell.

Cheers,

Kev E

Ok, no rush; it's purely academic for me.

Relays inside the headlamp shell, they must be quite small!

Hi Mark,

Yes the relays are quite small. They’re about the size of a 1 inch cube. I wrapped them in some foam and they went inside the head shell no problem.

You have to be very careful with your wiring and make a good job so that everything is neat and tidy and doesn’t end up looking like a birds nest. The use of modern electrical connectors help in achieving this, especially when you are ‘budding’ up earth connections and piggybacking.

The systems I design at work give me much more space to work in, but things can still get tight and you have to keep an eye on the sparky’s to make sure they are making things neat and tidy. See attached photo 😊

Cheers,

Kev E

B5CF43D8-A419-4F86-BD66-887015DB0D4E.jpeg
Kevin E #850760 06/05/21 11:29 am
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Kevin E Offline OP
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Here is a more detailed image of the electrical equipment in the headlamp shell.

I can see all the text clearly in my .pdf file, so hope that it comes out ok in this snipped .jpg image.

Cheers,

Kev E

Wiring 02.JPG
Kevin E #850761 06/05/21 11:34 am
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Kevin E Offline OP
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I can see now on here that the text still look a little fuzzy on the last image I posted, so try these two: -

Wiring 03.JPG Wiring 04.JPG
Last edited by Kevin E; 06/05/21 11:34 am.
Kevin E #850847 06/06/21 7:48 am
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Hi Kev, Mark.
Originally Posted by Kevin E
I like to keep the load off things like handlebar switches, so I have used a couple of relays. One is a changeover relay for the headlight main and dip beams
I've been fitting similar to Britbikes since my first rewire over the '82/'83 winter. Changeover relay for the headlamp, imho you're missing a trick - it might "keep the load off" the handlebar dipswitch but the headlamp current is still across the ignition and lighting switches contacts. Possibly academic if your bike has a common 60/55 QH headlamp, I use more powerful headlamp bulbs and separate on/off relays for main and dip. My T100 also has an Ammeter, its relay #30 terminals are connected to the same Ammeter terminal as the reg./rec. -ve wire, the headlamp draw shows on the Ammeter but then bypasses all the switches.

Originally Posted by Kevin E
the other is a simple on/off for the horn.
Depends on the horn? I like twin Fiamms, they come with a relay; standard Lucas or pattern are pretty shonky, low current draw, relay isn't really KISS? smile

Originally Posted by Mark Z
Relays inside the headlamp shell, they must be quite small!
Originally Posted by Kevin E
about the size of a 1 inch cube. I wrapped them in some foam and they went inside the head shell no problem
thumbsup Link to image. Tidy wiring inside the headlamp shell, my T100 has two plus connecting plugs. Nevertheless, any concerns about space inside the headlamp shell, there's a common even-smaller "micro relay" available in both on/off and changeover; previously-posted has been that Chrysler use them in the US?

Hth.

Regards,

Kevin E #850848 06/06/21 8:00 am
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I was contemplating fitting another relay that would be operated by the ignition switch and carry the load to the fuse box but then I had a think about it and decided, for me, it wasn’t necessary. The problem with switches carrying full load is that you get arcing across the contacts, which eventually burns them out.

I won’t be turning my ignition switch on while I have the lights, or horn on, so by the time any full load is being switched the ignition switch contacts will already be made, so no arcing is possible.

The other thing that also helps with load, is modern LED bulbs.

Cheers,

Kev E

Stuart #850849 06/06/21 8:06 am
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Kevin E Offline OP
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Originally Posted by Stuart
Hi Kev, Mark.
Originally Posted by Kevin E
I like to keep the load off things like handlebar switches, so I have used a couple of relays. One is a changeover relay for the headlight main and dip beams
I've been fitting similar to Britbikes since my first rewire over the '82/'83 winter. Changeover relay for the headlamp, imho you're missing a trick - it might "keep the load off" the handlebar dipswitch but the headlamp current is still across the ignition and lighting switches contacts. Possibly academic if your bike has a common 60/55 QH headlamp, I use more powerful headlamp bulbs and separate on/off relays for main and dip. My T100 also has an Ammeter, its relay #30 terminals are connected to the same Ammeter terminal as the reg./rec. -ve wire, the headlamp draw shows on the Ammeter but then bypasses all the switches.

Originally Posted by Kevin E
the other is a simple on/off for the horn.
Depends on the horn? I like twin Fiamms, they come with a relay; standard Lucas or pattern are pretty shonky, low current draw, relay isn't really KISS? smile

Originally Posted by Mark Z
Relays inside the headlamp shell, they must be quite small!
Originally Posted by Kevin E
about the size of a 1 inch cube. I wrapped them in some foam and they went inside the head shell no problem
thumbsup Link to image. Tidy wiring inside the headlamp shell, my T100 has two plus connecting plugs. Nevertheless, any concerns about space inside the headlamp shell, there's a common even-smaller "micro relay" available in both on/off and changeover; previously-posted has been that Chrysler use them in the US?

Hth.

Regards,

The 1” cube (appx.) relays were what I fitted to my bike during its first rebuild way back in the early 80’s. This time I will be using micro relays.

Cheers,

Kev E

Kevin E #850850 06/06/21 8:29 am
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Hi Kev,
Originally Posted by Kevin E
problem with switches carrying full load is that you get arcing across the contacts, which eventually burns them out.
I won’t be turning my ignition switch on while I have the lights, or horn on, so by the time any full load is being switched the ignition switch contacts will already be made, so no arcing is possible.
"no arcing is possible" ... mmm ... we're talking about cheaply-made switches attached to something that vibrates severely all the time the engine's running; ime of disassembled failed switches, you wish.

Originally Posted by Kevin E
The other thing that also helps with load, is modern LED bulbs.
A helluva lot more expensive than a second relay and a bit of wire? Especially as you've already paid for a (high-output?) 3-phase alternator?

Regards,

Stuart #850852 06/06/21 9:17 am
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Originally Posted by Stuart
Hi Kev,
Originally Posted by Kevin E
problem with switches carrying full load is that you get arcing across the contacts, which eventually burns them out.
I won’t be turning my ignition switch on while I have the lights, or horn on, so by the time any full load is being switched the ignition switch contacts will already be made, so no arcing is possible.
"no arcing is possible" ... mmm ... we're talking about cheaply-made switches attached to something that vibrates severely all the time the engine's running; ime of disassembled failed switches, you wish.

Originally Posted by Kevin E
The other thing that also helps with load, is modern LED bulbs.
A helluva lot more expensive than a second relay and a bit of wire? Especially as you've already paid for a (high-output?) 3-phase alternator?

Regards,

Interesting. I never considered the vibration factor in relation to the ignition switch. Maybe you have a point and I will fit a relay, as I originally planned to do.

3 phase alternator and LED bulbs. What can I say? It’s my bike and my choice. It would work perfectly well as a motorbike with the original 650 cylinders, but I’ve chosen to fit a 750 kit. I still have the original brakes though, so you may well say there’s another mismatch but once again it’s my bike, I’m the one that’s going to be riding it and it’s my choice.

Let’s all be happy with our choices eh?

Cheers,

Kev E

Kevin E #850853 06/06/21 9:29 am
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I used a similar concept, ended up with 4 relays,
1 master relay , energized by ignition switch, 25 A
1 Lighting relay , 1" cube
1 main beam/ flash relay, this gives the option for a spot light if wanted. , 1" cube
1 dip relay, micro relay in lamp shell

i used thin wires for the control switches and thick wires for the relays/ loads.

All japanese connectors, helps a lot with space saving in the headlamp.
No horn relay, I thought 5 was too many. So far no vibration failures of relays,. They are scattered around the bike, master under the coil bracket .
Lighting bolted to air box, mainbeam behind headstock,
dip in lamp shell.


71 Devimead, John Hill, John Holmes A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
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Kevin E #850876 06/06/21 4:46 pm
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This is not an argument, just another approach, in the name of simplicity: In place of the keyswitch, I have a very robust, all-metal toggle switch that has a screw-on rubber boot on the handle. I have another one of those on the headlamp shell which turns on the headlight and taillight. The only other switch on the bike (not counting the rear brake light switch) is a universal dipper/horn switch on the handlebar. No relays, no turn signals, no kill switch. Headlamp is sealed beam automotive, so no pilot bulb. No gauges (except for the GPS speedo, which is wired independently of everything else and has it's own on/off switch), so no gauge illumination bulbs.

The biggest exposure here is the dipper/horn switch, but I don't ride at night, so I never use the high beam setting, and the horn is likewise seldomly used. Furthermore, the horn is what I would call a non-essential function, at least not as essential as the ignition and lighting circuits, and the universal dipper/horn switch is cheap and easy to replace. The ignition, especially if it's EI, is sensitive to resistance in the circuit, whereas the horn is either going to work or not, and it will work until the switch is burned to the point where it no longer makes contact. My current dipper/horn switch has lasted, let me see... at least twenty years.


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Mark Z #850877 06/06/21 4:57 pm
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Originally Posted by Mark Z
This is not an argument, just another approach, in the name of simplicity: In place of the keyswitch, I have a very robust, all-metal toggle switch that has a screw-on rubber boot on the handle. I have another one of those on the headlamp shell which turns on the headlight and taillight. The only other switch on the bike (not counting the rear brake light switch) is a universal dipper/horn switch on the handlebar. No relays, no turn signals, no kill switch. Headlamp is sealed beam automotive, so no pilot bulb. No gauges (except for the GPS speedo, which is wired independently of everything else and has it's own on/off switch), so no gauge illumination bulbs.

The biggest exposure here is the dipper/horn switch, but I don't ride at night, so I never use the high beam setting, and the horn is likewise seldomly used. Furthermore, the horn is what I would call a non-essential function, at least not as essential as the ignition and lighting circuits, and the universal dipper/horn switch is cheap and easy to replace. The ignition, especially if it's EI, is sensitive to resistance in the circuit, whereas the horn is either going to work or not, and it will work until the switch is burned to the point where it no longer makes contact. My current dipper/horn switch has lasted, let me see... at least twenty years.

That’s cool Mark. I didn’t see anything as an argument, just a discussion between fellow BSA owners. We all have our way of doing things and if it works then all is well and good. I wouldn’t describe myself as an expert at anything and I’ve never got on well with people who think they’re ‘experts’. I know a little about the A65 and I’m learning more all the time. Electrics I certainly understand very well, having worked with the design and build of various types of electrical circuits for many years.

The reason for my original post was to share my electrical mods, which I believe are a big improvement over the standard system, with other A65 owners who might find it helpful. It will work with any type of alternator and does not specifically require a 3 phase type. It can also be further modified and changed to suit any individuals preference.

Cheers,

Kev E

Kevin E #850883 06/06/21 6:35 pm
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Hi Kev,
Originally Posted by Kevin E
3 phase alternator and LED bulbs. What can I say? It’s my bike and my choice.
Originally Posted by Stuart
A helluva lot more expensive than a second relay and a bit of wire?
... was an observation, not a criticism ...

Regards,

Stuart #850884 06/06/21 6:40 pm
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Originally Posted by Stuart
Hi Kev,
Originally Posted by Kevin E
3 phase alternator and LED bulbs. What can I say? It’s my bike and my choice.
Originally Posted by Stuart
A helluva lot more expensive than a second relay and a bit of wire?
... was an observation, not a criticism ...

Regards,

That’s not a problem Stuart, I didn’t take it as criticism.

My response was what it was because I have no logical, or rational reason for what I have chosen other than it suits me.

Cheers,

Kev E

Kevin E #850885 06/06/21 6:41 pm
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I wouldn’t design a road bike’s electrical system to be suitable for only certain defined conditions (eg daytime only, fast riding only etc).

There is no need to limit usage if the system is adequate.

There is no reason for the system to be inadequate with available components.

I agree with Stuart that a relay for the ignition switch is a good idea. Irrespective of whether the switch is operated under high current conditions or not, arcing still occurs (it’s the 12V that causes the arcing, not 12A).

What I focus on is the small contact area in the ignition switch, which carries the entire system current, which could be approaching 12A if using a high power headlamp as Stuart prefers.

Just having that level of current passing through that area is bound to generate heat at the junction, as the contacts wear it will be exacerbated.
Unless you enjoy replacing ignition switches occasionally, I’d put a relay in there.

I don’t know why folk use a separate relay for main and dip, a single switching relay such as

https://www.vehiclewiringproducts.co.uk/c-219-relays-flasher-units/p-646-12v-micro-relays

will do the job. I have 3 relays, one for ignition, one for lights, one for main/dip. They fit on a neat little dovetailed mounting under the front of the fuel tank. Should the main ignition relay fail (surely the worst failure), either of the others will work in its place to get me home. That hasn’t happened yet, but I don’t discount the inevitability!

All the relays (tucked just under the fuel tank) and the switches connect in the headlamp shell. The switching wires are all thinwall wires, the current carrying wires of heavier appropriate gauge, with the same colour coding. So if the worst happened, the wires could be connected inside the headlamp to get going again without relays.

I think relays are much more reliable than old ignition and lighting switches.

I don’t worry about the horn circuit much, are you from Turin?

Kevin E #850891 06/06/21 7:49 pm
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Looks like you've done a decent job on designing and installing the electrics on your A65, here's what I've done on my A65 and Norton over the last few years:-
- I've fitted similar relays on the A65 for headlight dip and main beam, this was mainly because I felt the original Wipac/Ducon main beam/dipper switch was inadequate and there was a fair amount of voltage drop. There wasn't much space in the headlight shell and I've now fitted a LED headlight bulb so the relays are probably not needed as the LED bulb uses so much less power.
- On the Norton I've fitted a better quality handlebar switch which controls the headlight on/off, dip/main, horn and indicators (if you have any), similar to This One, I felt this switch is more able to cope with the current so didn't use relays, and there is now barely any voltage drop, I'm now of the opinion that relays aren't needed assuming a modern switch is used and/or a LED light is used. The handlebar switch I used is similar to the one used by Colorado Norton on their bikes which I believe was originally intended for a Honda of some sorts. K & S industries in the US made my switch see this link, you can get them on Bay but the prices are now silly compared to a few years ago.
- I also used a 4 way fuse box on the Norton with blade terminals and spade connectors, I managed to fit it behind the left side panel, but there wasn't much space.
- I've been using spade terminals throughout the harness, together with the proper crimping tool. I usually add heat shrink tube between the cable and terminal to add extra strength & insulation.
- The harness is protected by self closing braided sheathing, see This Link this allows the sheath to be opened up should the need arise.

Hope this helps.

Last edited by gunner; 06/06/21 7:58 pm.

1968 A65 Firebird
1967 B44 Shooting Star
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koan58 #850893 06/06/21 7:52 pm
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Hi Dave,
Originally Posted by koan58
I agree with Stuart that a relay for the ignition switch is a good idea.
Not my idea, I've never fitted one; Gavin advised the idea?

Originally Posted by koan58
What I focus on is the small contact area in the ignition switch, which carries the entire system current, which could be approaching 12A if using a high power headlamp as Stuart prefers.
Nope, I never pass the headlamp current through the ignition switch.

Originally Posted by koan58
I don’t know why folk use a separate relay for main and dip, a single switching relay such as
https://www.vehiclewiringproducts.co.uk/c-219-relays-flasher-units/p-646-12v-micro-relays will do the job.
You haven't understood my previous posts on the subject:-

. because I've never switched the headlamp current with the ignition switch, a changeover relay doesn't work for me, because terminal #30 is connected to terminal #87b #87a when the relay is 'off'; i.e. whichever headlamp bulb filament was connected to #87b #87a would be on and working even when the bike was parked;

. otoh, an on/off relay for each headlamp bulb filament, when the ignition switch is off, there isn't any power to the dipswitch (that switches the two relays) so both relays are off, so both headlamp bulb filaments are off;

. I also don't have to switch a changeover relay to 'flash' the headlamp; headlamp dip on, if I press the 'flash' button, headlamp main is illuminated independently of headlamp dip.

Originally Posted by koan58
I have 3 relays, one for ignition, one for lights, one for main/dip.
Should the main ignition relay fail
either of the others will work in its place to get me home.
I don't have to worry about the "main ignition relay" failing because I don't use one; either of the headlamp on/off relays failing, the other can be used if necessary.

Hth.

Regards,

Last edited by Stuart; 06/06/21 10:18 pm.
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A potential problem with using mechanical relays in these old bikes is the vibration. Most modern bikes have balancers in the engine so it not much of a problem. Mechanical relays rely on a magnetic solenoid to keep the armature against the contacts with a spring trying to pull it off. Unless it is a contactor relay like used on the starter motor is does not have much force keeping it closed. Automotive relays are usually very isolated from engine and road vibration.
Besides, relays require power to keep them closed (unless you use a latching relay) so it is adding to the electrical load of the system.
Ignition switches are generally robust but modern ignition switches are better made. However, most all do not mount in the same way so it has to be moved or accommodated in some other way.
The handlebar switches are the worst for reliability, especially the later Lucas '71-.which rely on a spring copper contact that is overstressed and eventually makes poor contact. For those a remote switching device would be an improvement. A solid state switch or driver (like what is used in ignition systems) would be best except most are not made in module form. Using LED lamps would eliminate the need for relays except for the horn, and since that is used intermittently, a relay is the obvious choice.
For the ignition I would prefer a switch since there are less failure points, and occasional use. For the Wenco bike I used a threaded BNC connector. Cannot fall out and nearly nobody has one.
For theft deterrence a switch can always be bypassed by cutting and shorting the wires. Or simpler, put the bike in a trailer or pickup.

Stuart #850910 06/06/21 9:15 pm
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Thanks Stuart,
Perhaps I misunderstood this statement of yours?

“I've been fitting similar to Britbikes since my first rewire over the '82/'83 winter. Changeover relay for the headlamp, imho you're missing a trick - it might "keep the load off" the handlebar dipswitch but the headlamp current is still across the ignition and lighting switches contacts.”

This suggested that you avoided taking the lighting current through the ignition switch.

Which you confirm with:

“Nope, I never pass the headlamp current through the ignition switch.”

So as there isn’t an ignition relay, the lights are presumably supplied independently of the ignition switch? Is that what you mean? Can your lights be on when the ignition is off?


“. because I've never switched the headlamp current with the ignition switch, a changeover relay doesn't work for me, because terminal #30 is connected to terminal #87b when the relay is 'off'; i.e. whichever headlamp bulb filament was connected to #87b would be on and working even when the bike was parked;”

I can’t make sense of this, this relay is nothing more than a dipswitch, an option between high and low beam. It only has a function when empowered by the lighting supply/headlamp circuit, as always.

87A would be the default low beam (when no –ve power is being supplied to 85) , 87 would be high beam when 85 is –ve powered (assuming +ve ground) from the high beam handlebar switch.
There is no 87B. Terminal 30 should only be connected to the light switch supply, if it connects to either the 87 or 87A, then you are bypassing the relay to that headlamp filament.

I hadn’t considered the flashing headlamp aspect, I doubt I’ll give it much more thought. So going back to basics, your lighting load doesn’t go through your ignition switch, but does your ignition switch when turned off prevent the lights being turned on?

koan58 #850919 06/06/21 10:15 pm
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Hi Dave,
Originally Posted by koan58
Perhaps I misunderstood this statement of yours?
Originally Posted by Stuart
I've been fitting similar to Britbikes since my first rewire over the '82/'83 winter. Changeover relay for the headlamp, imho you're missing a trick - it might "keep the load off" the handlebar dipswitch but the headlamp current is still across the ignition and lighting switches contacts.
as there isn’t an ignition relay, the lights are presumably supplied independently of the ignition switch?
Correct. Same paragraph:-
Originally Posted by Stuart
My T100 also has an Ammeter, its relay #30 terminals are connected to the same Ammeter terminal as the reg./rec. -ve wire, the headlamp draw shows on the Ammeter but then bypasses all the switches.

Originally Posted by koan58
Can your lights be on when the ignition is off?
No; from my previous post:-
Originally Posted by Stuart
an on/off relay for each headlamp bulb filament, when the ignition switch is off, there isn't any power to the dipswitch (that switches the two relays) so both relays are off, so both headlamp bulb filaments are off;

Originally Posted by koan58
Originally Posted by Stuart
. because I've never switched the headlamp current with the ignition switch, a changeover relay doesn't work for me, because terminal #30 is connected to terminal #87b #87a when the relay is 'off'; i.e. whichever headlamp bulb filament was connected to #87b #87a would be on and working even when the bike was parked;
this relay is nothing more than a dipswitch,
It might be for you, because you supply its terminal #30 from your "ignition relay", or Kev intends to supply his from the "Light Switch"; in either case, the power to the changeover relay terminal #30 is cut when the ignition switch is off.

Otoh, I supply the headlamp either direct from the battery or from the aforementioned Ammeter terminal; the relays themselves are the only switches between battery -ve and the headlamp bulb filaments.

Anyone using relays to supply the headlamp is using two relays: either a relay switched on/off by the ignition switch, which supplies the changeover relay switched by the dipswitch ... or two relays switched by the dipswitch. In the latter case, as I say, ignition switch off, no power to the dipswitch, both headlamp relays off. thumbsup

Hth.

Regards,

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Stuart #850958 06/07/21 8:46 am
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Originally Posted by Stuart
Hi Dave,
[quote=koan58]I agree with Stuart that a relay for the ignition switch is a good idea.
Not my idea, I've never fitted one; Gavin advised the idea?


Not me, my Boyer is not relay fed, I reckoned the ignition switch should manage 3 amps.



Originally Posted by koan58
I don’t know why folk use a separate relay for main and dip, a single switching relay such as
https://www.vehiclewiringproducts.co.uk/c-219-relays-flasher-units/p-646-12v-micro-relays will do the job.

i did this because i wanted a spot light option, also, the flash button will power the main beam relay if dip is in operation, which wont work with one relay for dip and main beam.


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Hi Gavin,
Originally Posted by gavin eisler
Originally Posted by koan58
I agree with Stuart that a relay for the ignition switch is a good idea.
Originally Posted by Stuart
Not my idea, I've never fitted one; Gavin advised the idea?
Not me
blush Ooops, sorry 'bout that ... it was/is somewhere in the thread before Dave's first post ... help

(or "It wasn'y me, a big boy did it an' ran away"? grin ).

Originally Posted by gavin eisler
my Boyer is not relay fed, I reckoned the ignition switch should manage 3 amps.
thumbsup My thinking too.

Regards,

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