Mass of wiring underneath tank

Hi all.

New to the forum & fairly new to Norton ownership! I inherited my old man's 1974 Norton Commando 850 MkIIa along with a short list of issues that needed rectifying, one of which was the wiring.

I've stripped the old one out and put a new cloth wrapped Lucas harness in. It all went in easy enough and it's tidied the whole motorbike up but the mass of wiring under the tank is now fairly unbearable & causing issues with clearance.



Image above ^

I'm also battling with a Boyer micro MkIII & a power box so room is tight.

Any tips & tricks?

Those orange connectors they have used to replace the originals are good but also much larger, hence your lack of space. You need to go back to current reliable replacements for the Lucas bullet and sleeve connectors or something with the same low profile. I would not use a powerbox, they have an alternative to the 2MC capacitor inside for non battery starting but they are just as unreliable, when that fails it can take the whole powerbox out. A normal regulator/rectifier is safeer and you can also fit a modern version of the 2MC separately and this can be easily taken out out circuit on the roadside.

Welcome Luke,

Those bulky non-standard connectors aren't helping matters but the wiring does look as if it could be tidied up a bit?

Luke Turner said:

I'm also battling with a Boyer micro MkIII & a power box so room is tight.

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Moving the Boyer box to the underside of the coil bracket would make some additional space for the connectors.

No doubt you have a big time mess. At the INOA rally my camping neighbor was in the same predicament. We had an on the spot tech session about "quality" assembly of the under tank components. It is just as important if not more so than a shiney tank paint job.
Just throwing a pile of parts in a hap-hazzard fashion is what gives problems.
I use a very precise formula that I use for any bike assembly. It will vary for each type of bike.

The below boyer box mount which goes in exactically the same fashion as the lucas rita mount.
This mount removes it from where you have it and moves it between the coils where it is cooled in the air stream for longevity...then give room for the rest that needs to be above the 1" bar. It is open bottom. slide the boyer in and secure with one tie wrap. done. easy side of the road access




I have several more steps that make the under tanks neat and much better functionality of all components.
Interested?

Yes. Thanks Dave

the under tank wiring situation is a nightmare isn't it, id be interested in hearing what others have done.

With probably well over a half dozen tasks/areas that can be addressed, one that many may be aware of. The boyer mount above is very effective but does require some effort.

1. On the series 2 bikes (71+) the harness has the police horn wires. IF you have a vinyl wrap harness, that bunch of wires can be eliminated to lighten the load.Nice to do but not essential. This task is not practical for cloth harnesses.

2. Proper laying of all the control cables to prevent congestion and improve function by keeping the largest radius of bend possible. For me, I always route the throttle cable by crossing over to the left side of the neck, and the choke cable to the right side of the neck.

3. I do NOT constipate everything with lots of tie wraps. I have minimal and strategically place tying only. Example: the properly routed clutch cable is only tied at one spot...as indicated in the INOA tech digest 20 years ago. that is.. exactly where the right side rising diagonal frame tube meets the backbone. Clutch cable exits the right side of the neck and crosses over to the left of course going to the clutch lever. I tie wrap the clutch cable ONLY at this point and leave out the wire bundle. All 3 styles of oil tank allow this path from gearbox to the frame tube junction as described.

4. "girdle" for lack of a better name: 1-2 or 3 tie wraps (black?) in one loop, looping over the main backbone tube and routed below the 1" tube , forward of the tank coil mount. This is for restraining ALL wires and cables and keeping them off the tank but close to the neck. Notice all wires, and cables pass through but are not "tied" down.

A few more to follow in my next post.

Hello Luke,

what I do recommend to anybody riding an old british bike:

take out all old wiring harness when there is any problem.....make yourself a new wiring harness.....take out any component or wire that is not needed in the system .....take 1.5mm² wire for all the wiring except the ground wire - therefore take 2.5mm² [do many ground wires!].......put some relays for horn, dimlight and high beam....put in a good regulator/rectifier.....put in a good electronic ignition....take good crimp connectors....soldering isn`t always the best solution for a motorcycle......thin soldered wires break very easy

troubleshooting an old wiring harness is no fun at all and is realy annoying....especially when you break down with your moped when you are on vacation in a foreign country....

I draw myself my tailor-made-wiring diagram and print them on pdf..... so i have it on my cell phone

chris

dynodave said:

1. On the series 2 bikes (71+) the harness has the police horn wires. IF you have a vinyl wrap harness, that bunch of wires can be eliminated to lighten the load.Nice to do but not essential. This task is not practical for cloth harnesses.

Click to expand...

If doing this task, get some harness wrap. It is not expensive. It is like electrical tape with NO glue. NEVER use electrical tape on the actual harness wires. Short turns of electrical tape is used over the black harness wrap at the end of the runs...How many times have you seen the black sticky mess left by an amature!

To note to self for future reference, unused wires should receive 3/4" piece of shrink wrap over the bullet. Yes, I guess you could just cut them off. I really hate to chop them off on the handlebar switches, you may want to put turn signals some day...

Luke Turner said:

Hi all.

New to the forum & fairly new to Norton ownership! I inherited my old man's 1974 Norton Commando 850 MkIIa along with a short list of issues that needed rectifying, one of which was the wiring.

I've stripped the old one out and put a new cloth wrapped Lucas harness in. It all went in easy enough and it's tidied the whole motorbike up but the mass of wiring under the tank is now fairly unbearable & causing issues with clearance.



Image above ^

I'm also battling with a Boyer micro MkIII & a power box so room is tight.

Any tips & tricks?

Click to expand...

I just received a Lucas wiring harness from Clubman Racing. It has all the original type connectors under the tank, none of those huge multi connectors. Are you sure it's correct?

Blimey, some very interesting & detailed replies, thank you!

I've just popped out to the garage to kick her over for the first time since putting the new harness in & she started first time! Brilliant! Now I know it all works I can start to strip things back & tidy it all up.

The orange connector blocks you can see are Wagos (221). I'm an apprentice electrician (domestic & industrial) & we use these daily for stranded wires so I thought I'd use them whilst getting my harness together, they're incredibly quick to terminate so make it a doddle when you're moving wires around and testing different circuits. They aren't environmentally sealed but then neither are bullets. I coated the end of each wire in dielectric before pushing them into the terminal & clamping it down. Give it a good tug test & you're good to go.

They aren't that much bigger than a bullet either but I either need to move my Boyer power box back to the battery tray or sack it off in favour of the original capacitor, rectifier & zener.. I've got so much spare room in my battery box at the minute so I'm leaning towards the latter. Or, I find a way to mount the Boyer power box under the battery tray.

I have a fair chunk of unused wires which I could lose (condenser pack, ballast resister, contact breakers, blue lamp flasher unit etc) how easy is this on a cloth wrapped harness? I don't want to start trying to get them out to realise I've made a mess of the new harness.

For some reason Norton wire harnesses have a lot more wires than necessary. I pulled off a commando harness and did an autopsy. There are 19 red ground wires. count 'em. Some are bundled into one terminal. There are 17 brown-blue wires going hither and yon. Now, when you put in a Boyer and a podtronics there is a massive amount of wire that can be disposed of. All the ignition Black-White and Black-Yellow
wires can be thrown away. The alternator wires can be thrown away. This leaves a nice, thin bundle of wires. Rather than wrestle with an old harness with hidden problems and wires with old tape residue, and all the female connectors have corrosion and or oil on them, impossible to get a trustworthy connection, I enjoy taking wire cutters to the bunch and start with fresh wires and connectors. Japanese bullets work quite well.
Here's a good way to look at it....the grounds have to be the best and simple. The 12V wire Brown-Blue needs a fuse and then some version of a buss bar to distribute power. Usually a headlight switch and key switch. I usually put the ignition on its own circuit. Keep that in mind and the electrical is not so mysterious. I buy most of my wiring supplies from a place called AUTOMOTIVE ELECTRICAL SUPPLIES in the UK. They have all the color codes and the terminals are good quality unlike some of the cheap, thin metal ones from ebay. They also have something called THIN WALL WIRE and you wouldn't believe how much amperage a tiny diameter of wire can carry. This is usually impractical wire for most wiring but works very well for the battery wires, red and Brown-blue, and the yellow alternator wires. The alternator is yellow because the podtronics wires are yellow. This gives some info, I could go on a lot longer.

Luke Turner said:

how easy is this on a cloth wrapped harness? I don't want to start trying to get them out to realise I've made a mess of the new harness.

Click to expand...

Cloth is best left alone, see Dynodaves post, those Waga connectors only take wires in one direction and so either one half of the harness wires have to turn through 180 degrees or both via 90, there will be a better alternative now you know which wires connect where.

I'd always hated the rat's nest wiring harness on my 750 as it looked prone for trouble. After a bit of an event with a clutch cable earthing out due to what was probably the wrong routing I had a total custom rewire by http://www.motorcyclewiringspecialists.co.uk
There's not one unnesserary joint on the bike now and no bullets at all.
Also it employs three relays and four fuses.
(stainless oil line now covered to avoid the wire rope cutting effect and I put an extra layer of protection around the harness where it goes around the headstock.

@Dommie Nator Mark - that is a thing of beauty! It really calms my OCD!!!

Lovely job that Cab!

When you say ‘no bullets at all’ do you mean no bullets at all?

If so, what’s used instead in the headlight / battery tray area / etc?

Dommie Nator said:

I'd always hated the rat's nest wiring harness on my 750 as it looked prone for trouble. After a bit of an event with a clutch cable earthing out due to what was probably the wrong routing I had a total custom rewire by http://www.motorcyclewiringspecialists.co.uk
There's not one unnesserary joint on the bike now and no bullets at all.
Also it employs three relays and four fuses.
(stainless oil line now covered to avoid the wire rope effect and I put an extra layer of protection around the harness where it goes around the headstock.View attachment 10923 View attachment 10924

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Tell us more about the coil mount. Looks like a Boyer coil. I like it.

norton73 said:

Tell us more about the coil mount. Looks like a Boyer coil. I like it.

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Yes, it's the Boyer and heatsink combo.

Fast Eddie said:

Lovely job that Cab!

When you say ‘no bullets at all’ do you mean no bullets at all?

If so, what’s used instead in the headlight / battery tray area / etc?

Click to expand...

I can't remember what they were called exactly but Jap style.
Bullets be gone!
Total rewire sticking to original colours where possible.Not that there's a lot of it anyway with no indicators. I did away with the headlight switch in the lamp bowl. I didn't see the point when you had to turn it on at the main switch anyway, less to go wrong I thought.
There's the power box (I vented that into the airbox) three live fuses, one earth fuse and three relays in the battery area.
(that breather pipe has gone now as of engine rebuild last year).
I had this all done about 1,500 miles ago.

gtiller said:

@Dommie Nator Mark - that is a thing of beauty! It really calms my OCD!!!

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...until you notice the writing on the coils is upside down and there's nothing you can do to change it...arghh!