What Did You Do With Your Commando Today?

L.A.B. · Oct 11, 2022

Shelby-Right said:
My ignition light stopped working after I did my iso's , I had pulled the fairly loose spades from the , I think it's called the assimilater , under the tank stuck in that spring mounted to the side of the coil . I just cleaned all mine up slight squeeze to the spade terminals and adjusted the wires not to pull .cheers .

However, loose assimilator connections wouldn't be the cause of the lights, horn etc. not working but perhaps some connections under the fuel tank could have been loosened.

L.A.B. · Oct 11, 2022

Starvingphotog said:
Yes, I did take the tank off a few days ago when I was replacing some nuts for the head steady with Nyloc nuts. When I re-assembled maybe I disturbed the spade connectors and on my previous ride the engine had shaken enough to dislodge them and giving reason for it to not start today and also illuminate the ignition light. I will check that out as well.

If it still has the rubber double 5-way connector then it should be replaced along with any other single or double-common connectors as the internal sleeves become corroded and brittle.

bullet connector junction block - source, part number

pretty sure this is original to my 74 Mk2. hitting a search dead end. i would like to replace with the same. (lucas) female bullet connector - junction block. not sure what to call it - 5x2 (???) source, part number? found 5x1, but no 5x2. i can do work-arounds, but trying to keep the...

www.accessnorton.com

Starvingphotog · Oct 12, 2022

Good call Les. I think it is a newer cluster, last time I looked at it. I'll check that as well while I'm in there. I'm tempted to just bring it in the house for the season to tear it down some and clean and repair, but I feel that I would like to start it up one more time and take it for one more ride before I call it a season...

L.A.B. · Oct 12, 2022

Starvingphotog said:
I'm tempted to just bring it in the house for the season to tear it down some and clean and repair, but I feel that I would like to start it up one more time and take it for one more ride before I call it a season...

Unless there's a break in the earth/ground to the battery(+) then it would be unusual to have three separate circuits (white, brown/green and blue/yellow) so basically, almost the complete electrical system fail simultaneously which suggests the fault is more likely to be between the battery(-) and the ignition switch (brown/blue to T1) or within the switch itself.

Starvingphotog · Oct 12, 2022

Well, your analytical and systematic approach to problem solving on these beautiful machines is uncanny Les!
You got me all worked up over here and I just went out to the garage to follow your hunch on the systemic fail idea, and sure enough the 20A fuse was blown. This, of course, is between the battery and the ignition switch. Not sure why the fuse blew, but I would like to investigate it first. After my ride on Monday, I did change the oil, and count the teeth on my front sprocket so that I can order my correct chain (i.e. 20T is my front sprocket). I wonder if oil spilling around as I poured in fresh oil may have caused a short somewhere. I say this because I did spill a few ounces when the oil bottle tipped over on me.

L.A.B. · Oct 12, 2022

Starvingphotog said:
I wonder if oil spilling around as I poured in fresh oil may have caused a short somewhere. I say this because I did spill a few ounces when the oil bottle tipped over on me.

Unlikely I would have thought because oil is normally an insulator so perhaps you shorted a wire.
I was going to ask if you had checked the fuse but I thought surely you'd have already done that.

Starvingphotog · Oct 12, 2022

That's what worries me. I figure it takes a lot to blow a 20A fuse, and assume (without looking at the manual) that's the correct amperage to use. I'm going to look over the wiring to see if there's any breaks anywhere. It could happen anywhere on the loom, so a closer inspection is in order I think. Maybe when it's in the house, allowing me to take a few more rides before winter hibernation sets in.

Thanks for coaching me through this Les, and you too S-R on the assimilator. That thing is a strange little bugger.

L.A.B. · Oct 12, 2022

Starvingphotog said:
That's what worries me. I figure it takes a lot to blow a 20A fuse, and assume (without looking at the manual) that's the correct amperage to use.

Just slightly more than the original Lucas 35A blow rated (17A continuous) fuse.

What Did You Do With Your Commando Today?

Starvingphotog · Oct 12, 2022

Hmm, curious. I wonder if those are available here in the USA. I've never seen a variable type fuse like that before. But that's not saying much since I'm no electrician or mechanic. Worth a look around though.
Thanks for sending this nugget of knowledge Les!

L.A.B. · Oct 12, 2022

Starvingphotog said:
I wonder if those are available here in the USA. I've never seen a variable type fuse like that before.

Yes, they are available in the USA...

35 Amp Glass Fuse

BritshWiring is your complete source for wiring harnesses, components and accessories for your classic car restoration project.

www.britishwiring.com

"35 Amp Glass Fuse. (British Rating)"

...however, the old Lucas blow rating isn't generally used now so fuses are generally marked with their continuous rating. Owners often prefer to use blade fuses as they seem more reliable and easier to buy.

Just be sure not to replace a 35A blow-rated fuse with a 35A continuous or your wiring will become the fuse!

https://triumphtr6.info/Manuali/fuses.pdf

Shelby-Right · Oct 12, 2022

Starvingphotog said:
Good call Les. I think it is a newer cluster, last time I looked at it. I'll check that as well while I'm in there. I'm tempted to just bring it in the house for the season to tear it down some and clean and repair, but I feel that I would like to start it up one more time and take it for one more ride before I call it a season...

If you get it in the house , starting it in the hallway can cause issues with those long rugs , on a wooden floor ! , yep that rug took off , my mate with his trident , he didn't have a misses .

Starvingphotog · Oct 12, 2022

Thanks Les. I ordered 5 British Rated fuses just for fun

I totally see your point with mistakenly substituting a blow-rated 35A for the current continuous-rated 35A. I will definitely try NOT to make that mistake. Right now, a standard 20A blade-type fuse is in the bike. When these Brit types come in I'll swap them out.

S-R, right! In fact, when My Combat showed up two Januaries ago I brought it straight into my office where it still resides. I did start it up in the house with the pipes pointed outside and right up to the outside door in my office. It's an old house and the room I work in used to be a doctor's office so he would see patients here and not disturb the rest of the household. So, there are two front doors on the porch. I was so excited to get it running, and at the time didn't realize that it being air cooled meant that I shouldn't run it too long like that. To this day I can't remember how long I had it running at one time, but it wasn't that long. I do remember that my wife had hung new curtains in my office and the wind from the window blew against the curtain and it touched the hot exhaust pipe and melted on the pipe. I figure when I get the Combat out next summer that a little bit of riding will burn that off, but will likely leave an unsightly smear on the pipe. Oh well. Live and learn.

L.A.B. · Oct 12, 2022

Starvingphotog said:
I totally see your point with mistakenly substituting a blow-rated 35A for the current continuous-rated 35A. I will definitely try NOT to make that mistake.

Ok, but it's: Don't replace a 35A blow-rated fuse with a 35A continuous.

Durite 35A Aqua Green Auto Blade or Spade Fuse | Re: 0-375-35

Durite 35A aqua Green standard automotive blade or spade fuse at Arc Components Ltd. 35 Amps plug-in circuit protection fuse for car, van and commercial vehicle.

www.arc-components.com

"35 Amps continuous rating, 70 Amps blow rating."

Durite 20A Yellow Auto Blade or Spade Fuse | Re: 0-375-20

Durite 20A Yellow standard automotive blade or spade fuse at Arc Components Ltd. 20 Amps plug-in circuit protection fuses for car, van and commercial vehicles.

www.arc-components.com

"20 Amps continuous rating, 40 Amps blow rating."

Starvingphotog · Oct 12, 2022

10-4 Les

I got it.

So, took a look again at the bike and this time when I replaced the 20A fuse, there was a "poof" sound and smoke and all lights went dead. I also noticed that the Earth connector dangling by the Zener made a slight spark when it hit the Zener. I remounted the Earth connector by the Zener to the frame. I also took the tank off to investigate that "poof" and smoke. I found that the connector bundle was quite ugly and worn. Likely the suspect? Maybe. I redid it with new connectors just now. Hopefully re-assembled the wires to mate with the correct wires in the bundle...

Put a new fuse back in, and lights up correctly, and no "poof". I called it a night and plan to check it over again tomorrow and take it for a wee ride around the block or so to make sure all's well with the electrics. I think though, at some point soon, I will pick up a new loom to rewire the thing just in case some wires are burnt somewhere.

ashman · Oct 12, 2022

Your wiring looks pretty good for its age, but those big connector blocks not looking so good, that will be your problem, they are prone to failure, they rust as well fall apart from age, I do all my own wiring, my Norton has min wiring and with the Joe Hunt maggie even less wiring and most of my wiring is under my seat where I also have a very small battery and only have wiring to the head light, tail light and horn to the front and rear bake light to the rear, I only have a brake light switch on the foot brake and a earth wire that goes the full length of the bike with 4 mountings, I run my earth wire separate from my power wires and one earth wire for the on/off kill switch for the maggie.
I only ride my Norton in the day so very rarely have to use my head light at all, I keep my wiring simple and less troubles in the long run.

Ashley

johnm · Oct 13, 2022

Starvingphotog said:
10-4 Les I got it.

So, took a look again at the bike and this time when I replaced the 20A fuse, there was a "poof" sound and smoke and all lights went dead. I also noticed that the Earth connector dangling by the Zener made a slight spark when it hit the Zener. I remounted the Earth connector by the Zener to the frame. I also took the tank off to investigate that "poof" and smoke. I found that the connector bundle was quite ugly and worn. Likely the suspect? Maybe. I redid it with new connectors just now. Hopefully re-assembled the wires to mate with the correct wires in the bundle... Put a new fuse back in, and lights up correctly, and no "poof". I called it a night and plan to check it over again tomorrow and take it for a wee ride around the block or so to make sure all's well with the electrics. I think though, at some point soon, I will pick up a new loom to rewire the thing just in case some wires are burnt somewhere.

View attachment 100555 View attachment 100556

Hope your bike starts in the morning.

I looked to see what sort of ignition you have but couldn't see it, because when I blew the fuse on my bike due to a short at the zenor it destroyed the Pazon black box. Confirmed by Pazon when I sent it for testing.

The fuse rating was too high to protect the Pazon. I now have a separate fuse ( 5 amp ??? ) on the feed to the Pazon. Not sure if that's a good idea but it does work.

Starvingphotog · Oct 13, 2022

Yikes! I didn't think about frying the Pazon. I have a Pazon on there that was installed by the previous owner. I guess I'll see if it starts, or at least if the plugs spark when I turn the engine over with ignition on. I'll let you now how it goes today. Hopefully I have good news, otherwise, John I'll be reaching out to you on what you did to repair your Pazon.

Ashley, yes, the junction was in pretty bad shape, and the aluminum connectors broke with me manipulating them to pull out the bullet connectors. Good call there with Les to update that bit. The rest of the wiring up there looks good. I really like your approach to simplifying the wiring to under the saddle. Safer as well, with only minimal and straight through wiring going under the tank. Do yourself a favour though mate, and ride with your lights on. Easier for others (i.e. distracted drivers texting or talking) to see you this way.

Starvingphotog · Oct 13, 2022

By the way Ashley, that link that Les sent me to British Wiring here in the USA has complete main and headlight harnesses that look pretty, but not minimal like you're describing. I was thinking of buying a complete set from them. Pricy at $US320, including shipping.

Norton

BritshWiring is your complete source for wiring harnesses, components and accessories for your classic car restoration project.

www.britishwiring.com

Starvingphotog · Oct 13, 2022

Mart UK said:
I have the same shape filter on my single Amal 34. It replaced a much larger K&N, which I felt was too tight under the frame. I didn't expect it to be a straight swap, thought it would affect the carb's breathing. But, it runs exactly the same, which is really well in my mind. But, I don't have any other Commando riding experience to draw on. It idles fine, takes off on the throttle, without any hiccups and pulls to 6000 (self imposed max limit) very happily.

Hey I wanted to pick this thread up again to point out something lost with these wee filters. That is, the stock setup allows for a slight vacuum in the oil tank for the breather to pull from the engine crankcase. When you put one of these cone filters on, or something similar, the slight vacuum of the carbs disappears from the oil tank, and the crankcase isn't actively breathing. What do you guys think? Is my thinking and logic correct here? I wonder if these aftermarket breathers solve this problem, or you just have to do something similar to stock to re-introduce this hose from the oil tank to the air filters to re-establish this active breathing of the crankcase.

Starvingphotog · Oct 13, 2022

johnm said:
Hope your bike starts in the morning.

I looked to see what sort of ignition you have but couldn't see it, because when I blew the fuse on my bike due to a short at the zenor it destroyed the Pazon black box. Confirmed by Pazon when I sent it for testing.

The fuse rating was too high to protect the Pazon. I now have a separate fuse ( 5 amp ??? ) on the feed to the Pazon. Not sure if that's a good idea but it does work.

Well John, I just went out in the garage to do a quick test of the ignition and with the key at the on position and ignition light on, and plugs pulled and resting on the block, no spark when I turn over the engine. I think I can assume that my Pazon black box is fried as yours did. What sort of short did you have at the Zener that made your fuse blow? Also, to remove the black box for inspection and testing it looks like I have to remove the lead from the Pazon black box that connects inside the timing cover. This is new territory for me and I have no idea what I'm doing on that side of the engine.

What Did You Do With Your Commando Today?

L.A.B.

Moderator

L.A.B.

Moderator

bullet connector junction block - source, part number

Starvingphotog

L.A.B.

Moderator

Starvingphotog

L.A.B.

Moderator

Starvingphotog

L.A.B.

Moderator

Starvingphotog

L.A.B.

Moderator

35 Amp Glass Fuse

Shelby-Right

Starvingphotog

L.A.B.

Moderator

Durite 35A Aqua Green Auto Blade or Spade Fuse | Re: 0-375-35

Durite 20A Yellow Auto Blade or Spade Fuse | Re: 0-375-20

Starvingphotog

ashman

johnm

Starvingphotog

Starvingphotog

Norton

Starvingphotog

Starvingphotog