Harness Installation

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Hi folks,

I am mentally preparing to install a new wiring harness in a 72 Commando and I have a few questions.

1) First, after reading a couple of related threads on here I've come up with a general plan, and I'm hoping to hear if people think it sounds ok. I'm planning to clean the parts of the bike I'll be working on and to take a bunch of photos before doing anything else. I've got a main switch that I rebuilt following technical instructions the LAB kindly provided. This is separate from the one on the bike so I can hook this up to the new harness before even putting it on the bike. This should make it easy to get all those connections right. Next I think I would cut out most of the old harness just leaving the connections to the components so I can still see those and can replace with the new wiring as I go. I've just restored the horn and I'm about ready to reinstall that now. I've got the back wheel and mudguard off at the moment so I can hook the horn up and install it following the main switch work I just described. I think I could connect that to the handlebar switch right away and test it. Then my plan is to just work from the battery box towards the back, and then towards the front doing one thing at a time.

2) I have a Podtronics single phase rectifier-regulator with capacitor that I'll be replacing the Lucas rectifier and Zener diode with. LAB informed me about this amazing device also. The installation instructions look pretty straightforward, but I am a bit confused about one small thing: should the black wire from this component go directly to the negative battery terminal, or should it be connected to the brown/white wire that would originally have gone from the original rectifier to the main switch?

3) And finally, LAB also kindly provided a link to a great website that sells wiring connectors. The only issue is that the business is in the UK and I'm in Canada. Does anyone know of companies that sell bullet and double or snap connectors (male and female) in Canada? I've had a little look but haven't had a whole lot of luck so far.

Thanks!!
 
3) And finally, LAB also kindly provided a link to a great website that sells wiring connectors. The only issue is that the business is in the UK and I'm in Canada. Does anyone know of companies that sell bullet and double or snap connectors (male and female) in Canada? I've had a little look but haven't had a whole lot of luck so far.
Thanks!!
Try British Wiring they are not in Canada but Pennsylvania
http://www.britishwiring.com/
per their website:
"British Wiring is now located in Bally, Pennsylvania, and ships products to the USA and Canada."
 
One more question: I'm not seeing any of the male flat connectors that go into what I think are called 'double' or 'snap' connectors. The only male objects I'm seeing are the 'bullet' style connectors. I have a couple of the ones I'm trying to find that I got from the bike now that are brass. The male side is just a flat tab, and the female has a double sort of end. The ones I have are the crimping type. I'm not seeing these on the relevant websites so far. Anyone know where these can be found?
 
Jamie .... sounds like you got a good plan .... my tip would be when working don’t get ahead of yourself or try and hurry , patience is key ... keep everything as tidy as possible and make nothing permanent until tested and verified that how you want it .... I get all my electrical , nuts and bolts etc. , at local place here in Truro ... E. Lynds Ent. I bet if you call them they could help you out reasonable prices , also use the heat shrink stuff extensively , not tape , have fun with it ....
 
Excellent, thanks Craig!! Sounds like E. Lynds Ent. are definitely worth calling - they're the closest so far by far :). Heat shrink is an excellent idea too. Thanks for that, I was definitely picturing tape until you said that.
 
2) I have a Podtronics single phase rectifier-regulator with capacitor that I'll be replacing the Lucas rectifier and Zener diode with. LAB informed me about this amazing device also. The installation instructions look pretty straightforward, but I am a bit confused about one small thing: should the black wire from this component go directly to the negative battery terminal, or should it be connected to the brown/white wire that would originally have gone from the original rectifier to the main switch?



A "brown/white wire...from the original rectifier to the main switch" is the pre-'71 electrical system.
I would expect a '72 model to have a brown/blue (NU) battery negative-to-Ign.Sw. wire, no ammeter and no brown/white NW wire (not to be confused with white/brown WN).
If it has the pre-'71 system ammeter* then the Pod. negative needs to be connected to the brown/white between the ammeter and the ignition switch.
If it does not have an ammeter then the Pod. negative can be connected to the battery negative-to-ign. Sw. wire or, directly to the battery negative terminal.

*(If you've bought a '72 (71-74) "harness" (main and headlamp sections?) then it won't have the ammeter wires).
 
Thanks for the Waldridge tip Oldbeezer, and thanks for the detailed answer on question #2 LAB! The harness I have is the main harness and it's apparently for 1970-74 Commandos, according to the label, it fits with your post-71 description. And you are correct about the wire on this new harness between the battery and main switch, and the rectifier and the main switch being brown/blue. There is no ammeter on the bike and I don't see it mentioned in the main harness instructions, and I see no brown/white wire in the harness/instructions. There are white/brown wires.

Just so I'm totally clear on this - its best to not connect to the brown/blue wire that would have gone to the original rectifier eh? Better to go straight to the battery negative to main switch or the battery negative terminal?

Thanks again,

J
 
There shd be a fuse between the battery and brown/blue, whatever else happens.
What i did was push the old "midpoint" grommet out, cut all the tape off the old main harness, and then pushed the new harness (made sure I had figured out which end of the new harness was headed forward) through the gusset in the frame AND the grommet alongside the old one.
Then connected the new one as I removed the old one, step by step. When this piece -by-piece routine was not practical, I hung labeled tags on the old wires. After unhooking the old and connecting the new, I pulled the old wires away and fit the grommet to the gusset.
There were a couple of unused wires on the new harness, which I just tucked into the headsteady.
I saved the old harness and found it was very handy to hook up other stuff with, or to replace the odd thing with stock colors. Good Luck!
 

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The harness I have is the main harness and it's apparently for 1970-74 Commandos, according to the label,it fits with your post-71 description.

It is actually '71-'74, so Lucas (or Wassell Lucas in this instance) has it wrong and it's not the only error on their diagrams. It's not exactly correct for '71 either, but no doubt it saves them making two almost identical harnesses, one for '71 and another for '72-'74.


And you are correct about the wire on this new harness between the battery and main switch, and the rectifier and the main switch being brown/blue. There is no ammeter on the bike and I don't see it mentioned in the main harness instructions, and I see no brown/white wire in the harness/instructions.

That is correct for '72. What complicated matters was your mention of a "brown/white rectifier wire" that a '71-on model (no ammeter) should be brown/blue.


There are white/brown wires.

Yes, white/brown (WN) is the charge warning lamp to assimilator wire.

Just so I'm totally clear on this - its best to not connect to the brown/blue wire that would have gone to the original rectifier eh?

"Not" would be for when an ammeter is fitted.



Better to go straight to the battery negative to main switch or the battery negative terminal?

As there is no ammeter you can connect Pod. negative anywhere between the battery and the main switch (as the original rectifier was) or connect directly to battery negative.
 
I shouda mentioned I wasted a lot of time trying to use NOS Lucas female bullet connectors, which broke at every opportunity.
And I used a dab of Vaseline for every new hookup.
 
Thanks Mr. Rick, LAB, Oldbeezer and Craig!! This has been very helpful as always. I definitely know some things I didn't know earlier today, and I'm feeling a lot more confident about this operation. I'll get things started and will check back in with updates, or with questions the next time I get scared and confused :).
 
A few other errors you are likely to find on the Lucas 54960724 diagram are the three wires marked "Blue Lamp Flasher Unit" which are the assimilator wires.
The two wires marked "Warning Light Assimilator" are the auxiliary socket wires.
Green/white is RH direction indicator, not "LH" as marked.
Green/red is LH indicator, not "RH" as marked.
White/yellow in the new harness would have been white/purple originally, however, as the white/purple (ballast to both coil negatives) weren't marked as such on the original factory diagrams this may go unnoticed especially if electronic ignition is fitted.

Lucas diagram 54960724
http://www.totalbikebits.com/wassell/orderpoint/prod_info/WW19082.pdf
 
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If you do call E. Lynds get them to sell you a tube of “dialectic grease” use it on all connections, once you are finished you will be glad you did ... I may have spelled that wrong but someone on here will correct me , they will know what you talking bout at Lynds either way ...
 
Id lean toward the tinned bullets not the brass ones. Over time corrosion sets in. And Id get all new
bullet females as well. Not to forget the correct crimpers. They arent cheap but they work and worth
the investment.
You can order from Uk for stuff , no? I always did.
 
the metal of Lucas bullets decays to loose grip or even crumble no grease can solve. There's often not enough wire length to replace terminals so another reason to renew loom. Bullets ain't bad in themselves just not inteneded to last this long. Do note about 1/3 the harness are useless dead end free loops and leads to nowhere for police items. Not bad ideal to trace and eliminate them. There special gripers to work bullets for the prim/proper and help protect flexing wire as it enters metal terminal to fracture weaken as fast.

I got to see a factory issued loom as was being cleaned off after decades in a shop. I never saw such as tiddy well routed and fastened organized motorcycle loom as that 73 750. Lucas makes world class jet fighter and rocket electronics since WWII just got to pay them more to get that quality.
 
supercat; where are you located, if you add a little more info to your personal page, you might be able to scare up some local assistance...

Okay so now i will be the contrary voice,!!! the new wiring harness and the british connectors should stay in the UK, (not to offend our UK friends) but I believe much better connectors and systems are available in north america now. i think you have not clearly defined you overall strategy.... are you going to go to LED's in the headlight/taillight, etc,, they will influence what you need for a wiring harness, my suggestion is build if from scratch use weatherpak connectors

just my 2bits
 
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