1974 850 MK2 Wiring

Discussion in 'Norton Commando Classic Motorcycles' started by EricWoods, Jan 13, 2018.

  1. EricWoods

    EricWoods

    Joined:
    Jan 10, 2014
    Hello. its been a while since i was in the forum. i need someone to rewire my Commando in England. Can anyone suggest a Person or Motorcycle Shop to do this
    Thanks
    Eric
     
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  2. kommando

    kommando

    Joined:
    May 7, 2005
    If you are replacing an existing harness with a new standard one it takes about 3 to 4 hours. Remove the tank, seat and battery. Cut the old harness near the hole where it passes through the frame and then pass the new harness through the grommet and lay on same route as old harness. There is a large 10 connector near the head steady that connects the headlamp harness and switch clusters to the main harness, start there and work you way back. Now undo each old harness connection noting the colour and remaking it with the new using same colour, cut the old harness as many times as you like to facilitate fitting the new harness as you work your way back. Worst bit will be getting to the horn, as mine does not work I put a new horn in a reachable location.
     
    Last edited: Jan 14, 2018
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  3. cliffa

    cliffa

    Joined:
    May 26, 2013
  4. Dommie Nator

    Dommie Nator VIP MEMBER

    Joined:
    Apr 2, 2013
    I got Richard Prowse of MWS
    to completely rewire mine from front to back with modern wire, (same colour coding, approx half the thickness and twice the rating) relays, various fuses, new coil pack, new reg/rect, new ignition unit etc. There's not a join anywhere and NO FUC***G bullets. It was prompted by a fire due to earthing out through the clutch cable so the insurance coughed up mostly although it was something I wanted done anyway.
    Ferret was going to take far too long (9 months) was more expensive (£1,000.00 plus parts) and wanted to use an original harness which I wanted to be rid of.
    http://www.motorcyclewiringspecialists.co.uk
     
    Last edited: Jan 17, 2018 at 12:04 PM
  5. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    Or do it yourself - it's very easy. If I can do it, anyone can.
    As Dommie Nator said, use modern thin-wall cable and modern connectors.
    Also, you can use negative earth/ground so that cheap LEDs can be used.
    Another plus is that you can use relays to trigger the headlights and horn - more power than being strangled by the original harness.
    OK, it may take a couple of days, but it's simple, rewarding, and cheaper than an off-the-peg harness.
    I dumped the old Zener diodes and selenium rectifier, using a modern regulator/rectifier.
    A few pics:

    [​IMG]

    Wago connectors instead of ghastly old bullets:

    [​IMG]

    Relays:

    [​IMG]

    Modern fuse boxes, instead of a single (something's gone wrong) glass fuse:

    [​IMG]

    Braided wiring:

    [​IMG]

    To be continued...
     
  6. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    And to stop the incandescent filaments vibrating themselves to death, I fabricated a LED rear lamp board:

    [​IMG]

    Cost? About £5/$6.50 - some retailers are charging £24/$30.
     
  7. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
    Silicon rectifier? (2DS 506 49072A/B) :)
    [​IMG]
     
  8. Dommie Nator

    Dommie Nator VIP MEMBER

    Joined:
    Apr 2, 2013
    Nice, but why the need for any joints? (under the tank).
     
    Last edited: Jan 17, 2018 at 9:50 PM
  9. NKN

    NKN

    Joined:
    Mar 28, 2016
    Nice job, IMHO I won't go with modern thin-wall cables. Not sure they were designed to go on vibrating bikes.
     
  10. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    Oops, I was getting muddled up with the older selenium rectifier and the silicon diode type that is fitted to the Commando. Thanks for putting me right, LAB. I come from the old school where we learnt by being corrected, unlike the modern generation that seems to take exception and offence from such action.
     
  11. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    I dumped the old Lucas switch gear in favour of Hinckley Triumph switch cubes (I think that's the modern parlance). There were many reasons for this:
    • The old switch gear was broken.
    • It was unintuitive.
    Having installed the new switch cubes, I had a number of options as to how to integrate them into the new harness:
    • Make the connections in the head lamp shell.
    • Use the original Molex connector.
    • Hard wire into the harness.
    • Swap the Molex connector for a couple of Superseal items.
    I had used the first option in my Trident, but I found the head lamp shell was too busy. The original Molex connector was not waterproof, so I discarded that idea. I didn't want to hard wire the switch cubes, as it makes later maintenance more difficult - what do you do if you damage a switch cube? Therefore, I cut off the Molex connector, and replaced it with Superseal connectors:

    [​IMG]

    These are connected to the main harness under the tank.
    Should it fail, I can easily buy another switch cube, and graft on a couple of new Superseals.
    Bonuses with using modern switch cubes are many, but it means I can switch on the head lamp without groping around under my left arse cheek when it gets dark.

    [​IMG]
     
  12. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    Thanks for the compliment. I'm happy with thin-wall cables, and I haven't had a failure yet. For reasons of strength, I won't go below 0.75mm², which I use for triggering relays and LED lamps. I use 1.00mm² for brake lights, and other relatively low-powered circuits. For horns and head lamps I use 2.00mm². For connecting the battery to a fuse box, I use 3.00mm². It's not very scientific, but it works for me.
     
  13. NortonMKIIA850

    NortonMKIIA850

    Joined:
    Jul 20, 2017
    Admirable work! I re-wired my bike with a new harness from one of the usual suspects about 17 years ago, it's still hanging in there but there have been and are faults and niggles. Much better to do it yourself, if you can get your head around it. Maybe one day ... One thing though, I never grope around under my left arse cheek while riding :D as I ride with the lights always on. Safety is the obvious reason, but a nice bonus is that, if a light fails, the chance of it happening after dusk is much reduced. Just a thought.
     
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  14. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    I actually ride all the time with a day-time running light in the form of an angel eye LED head lamp:

    [​IMG]

    It seems to get me noticed, and it doesn't put a strain on my single phase alternator.
     
  15. NortonMKIIA850

    NortonMKIIA850

    Joined:
    Jul 20, 2017
    Yes that does look good. By the way is that a pair of Fiamm horns you have there, mounted just ahead of the coils? If so, I've been on the point of ordering a pair myself, but I've wondered how prominent they'd be – definitely time I had louder horns, talking of safety! What's your take on their appearance on your bike? Might you share a photo or two to give us an idea? I had a pair on a Kawasaki Z650 back in the early '80s, they fitted perfectly and looked right under the bottom yoke, between the fork legs, but I can't see that working on my Commando. Cheers.

    p.s. Those Fiamms pretty much saved my life one time – I was barrelling along a motorway in the fast lane past a junction, in the corner of my eye I could see a car coming down a slipway onto the motorway, once it was on the motorway it just made a beeline (!) for the fast lane and me, like I wasn't there – I hit the Fiamms, and the car swerved away like it had been stung ... Definitely something to consider.
     
    Last edited: Jan 18, 2018 at 9:07 AM
  16. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    Yes, it is a pair of FIAMM AM80S horns. I consider loud horns to be essential in today's traffic, and they are loud. I positioned them next to the coils, and they are a tad ugly there, but I don't like the original position in the bowels of the machine.

    [​IMG]
     
  17. olbbeezer

    olbbeezer

    Joined:
    Nov 2, 2017
    Perhaps if you painted the red bits black they would not stand out so much.
     
  18. alan hodge

    alan hodge

    Joined:
    Oct 10, 2017
    hi I am interested in where to get that headlight and how it's installed
    thanks
    alan
     
  19. NortonMKIIA850

    NortonMKIIA850

    Joined:
    Jul 20, 2017
    Thanks for posting that photo bucksfizz! Now I'm wondering if some kind of bracket couldn't be made up so they sit up under the steering head/headstock, so long as they wouldn't hit the mudguard ... Painting the red bits black is an idea – my Z650 was red anyway so it didn't matter. Food for thought anyway, thanks again!
     
  20. bucksfizz

    bucksfizz

    Joined:
    Jul 21, 2016
    They're available on eBay: https://www.ebay.co.uk/itm/Angel-Ey...175085&hash=item58b8479e64:g:bpcAAOxynLhR-nKJ

    If you're looking at this after the item has dropped off, search for "Angel Eye Headlights headlamp RHD H4 for Land Rover Defender". Unfortunately, they come in pairs (for cars).

    I wired the LED outer ring into the pilot light circuit:

    [​IMG]

    It's the red wire that goes into the leftmost hole in the WAGO five-way connector.
    BTW, the head lamp is physically fatter than a regular head lamp, which means that you need to bend the W clips to mount it. However, it is still a 7" head lamp, so it will fit the outer ring.
     
    Last edited: Jan 18, 2018 at 2:38 PM

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