Battery compartment wiring

While waiting for the 080 clutch plate/spacer to arrive from OB, I decided to try and get the rest of this wiring finished up today. Just thought I'd run this by you all to see if anything looks familiar as to where it goes etc. Couple questions:

* Does the mounting of the zener diode in pic 1 look right, the way I've got it and the ground on the same attach point? Manual shows another ground going to cyl head (I assume to the center head steady bolt... which there is an unassigned ground in that vicinity) and another to each z plate. Got the one on the post with the zener but only have one other ground ring left that I assume will go to the battery. Do both z plates in fact get grounds?

* I'm pretty confident on the wiring of the rectifier, but where does it mount? I haven't been able to find anything in any of the manuals that shows this. Also, does the mounting screw ground it, meaning I'm going to have to remove powder coating around the mounting hole?

* As far as the 2MC Capacitor... wiring diagram shows double red going in and brown white coming out. Found a double red spade in the vicinity but no white brown anywhere in the batt compartment. Pic shows a white/purple that I mistook for white/brown till I looked closer at it with a flashlight.

* Where does the ballast resistor (I assume that's what it is) sitting on the z plate in pict 2 mount?

* There's a little red jumper laying on top on the primary case in pic 3. I remember that coming out of the headlight but cant remember where.

* Are the wires that go to the horn visible in any of these pics?

* I know some of these wires are not going to be used. Are any of these unused wires visible in any of the pics?

Got kind of excited yesterday when I started thinking how close this thing is to filling with fluids and giving a kick. Have to get the clutch plate from OB, finish the wiring, rebuild the fuel lines, install tank, side covers and fenders.

Robb2013 said:

* Does the mounting of the zener diode in pic 1 look right, the way I've got it and the ground on the same attach point?

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The ground terminal should not be placed under the Zener.

Robb2013 said:

Manual shows another ground going to cyl head (I assume to the center head steady bolt... which there is an unassigned ground in that vicinity) and another to each z plate. Got the one on the post with the zener but only have one other ground ring left that I assume will go to the battery. Do both z plates in fact get grounds?

Click to expand...

Unless it's an 850 Mk3 or a JPN with the high output RM23 alternator then there would normally be only one Zener (Edit: and ground wire) on the R/H Z-plate.

Robb2013 said:

* I'm pretty confident on the wiring of the rectifier, but where does it mount? I haven't been able to find anything in any of the manuals that shows this. Also, does the mounting screw ground it,

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The rectifier mounts to the frame plate at the rear of the battery compartment, and yes the stud should ground it.

Robb2013 said:

* As far as the 2MC Capacitor... wiring diagram shows double red going in and brown white coming out.

Click to expand...

I think you must be looking at the wrong diagram? The two 2MC brown/blue [NU] wire connectors in the photo go to the negative (common double) terminal of the 2MC.

Robb2013 said:

Pic shows a white/purple that I mistook for white/brown till I looked closer at it with a flashlight.

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The white/purple wire in that position has no function. [Edit: The White/red also has no function.] Both can be taped up.

Robb2013 said:

* Where does the ballast resistor (I assume that's what it is) sitting on the z plate in pict 2 mount?

Click to expand...

To the underside of the ignition coil bracket (points ignition only, it is redundant for electronic ignition).

Robb2013 said:

* There's a little red jumper laying on top on the primary case in pic 3. I remember that coming out of the headlight but cant remember where.

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Probably from the main or pilot bulb holder to a ground fitting inside the base of the headlamp shell?

Robb2013 said:

* Are the wires that go to the horn visible in any of these pics?

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Probably the purple (purple/black?) and red in pic 3.

Read through these two posts, they have alot of pics and I think it may answer a few of your questions.\

can-this-box-parts-commando-t13057.html
accuracy-wiring-diagram-the-shop-manual-t13125.html

ballast resistor goes between coils on the under side of the support bracket, an dyes that is the ballast resistor in pic 2.

L.A.B wrote
Probably the purple (purple/black?) and red in pic 3.

Click to expand...

Yes Rob this is horn wiring, and as you can see it starts in pic 2 in the battery box.

Does the mounting of the zener diode in pic 1 look right, the way I've got it and the ground on the same attach point? Manual shows another ground going to cyl head (I assume to the center head steady bolt... which there is an unassigned ground in that vicinity) and another to each z plate. Got the one on the post with the zener but only have one other ground ring left that I assume will go to the battery. Do both z plates in fact get grounds?

Click to expand...

- the ground has the larger ground loop on it to fit around the Z plate mounting bolt.

Manual shows another ground going to cyl head (I assume to the center head steady bolt... which there is an unassigned ground in that vicinity)

Click to expand...

-Yes the center head steady bolt looks most tidy.

* I'm pretty confident on the wiring of the rectifier, but where does it mount? I haven't been able to find anything in any of the manuals that shows this. Also, does the mounting screw ground it, meaning I'm going to have to remove powder coating around the mounting hole?

Click to expand...

-LAB is right, it goes on the frame web up behind the battery box towards the rear wheel, I believe the outer hole near the left hand side cover, I believe the other hole is for the flasher unit.

* I know some of these wires are not going to be used. Are any of these unused wires visible in any of the pics?

Click to expand...

The majority of the unused wiring, ( if your harness has it ) is up under the tank and if for the interpol version of the bike, you can see it tucked away under the tank in some of the photos on the first link I posted with all the photos.

Cheers

Thanks guys, great stuff. Couple questions though... my horn has 2 sets of contacts.. upper and lower. What's the deal with that?

Also, on the ballast resistor... here's a pic of the underside of my coil mounting bracket:



Does it mount in the center empty hole? Looks like something round was in there before. I kind of was under the assumption that the black Lucas box was the ballast resistor. Confused...

Here's a pic of the rect. and MC2, yours may be different colors and wires, this is the 69/70 version. I'd get rid of the MC2, it's most likely faulty anyhow or can go bad and strand you. But the spring mounts at the bottom of the rect.





Horn contacts don't matter, they're both above ground.

Dave
69S

Robb2013 said:

Thanks guys, great stuff. Couple questions though... my horn has 2 sets of contacts.. upper and lower.

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Connect one horn wire to each.

Ballast.

Robb2013 said:

Does it mount in the center empty hole?

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Yes.

Robb2013 said:

I kind of was under the assumption that the black Lucas box was the ballast resistor.

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The black (rubber) block contains the two ignition condensers. (The red ground wire is fitted incorrectly, it should connect to a tab at the base, with black/white to one projecting condenser tab and black/yellow to the other)

DogT said:

Here's a pic of the rect. and MC2, yours may be different colors and wires, this is the 69/70 version.

Click to expand...

For Robb's '73 model, the rectifier bolts directly to the frame without the bracket.

L.A.B. said:

The black (rubber) block contains the two ignition condensers. (The red ground wire is fitted incorrectly, it should connect to a tab at the base, with black/white to one projecting condenser tab and black/yellow to the other)

Click to expand...

Is there polarity on those two tabs or can either wire go to either side?

This is from my '74. Should be similar. Stud goes right through the back of the frame. This was before I fitted a $3 radio shack rectifier. One of my diodes broke right off the original.

Robb2013 said:

L.A.B. said:

The black (rubber) block contains the two ignition condensers. (The red ground wire is fitted incorrectly, it should connect to a tab at the base, with black/white to one projecting condenser tab and black/yellow to the other)

Click to expand...

Is there polarity on those two tabs or can either wire go to either side?

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Both are negative, so black/white or black/yellow can go to either (pull the rubber cover off and all should become clear?).

Here are a couple more before pics that may be of some help:

L.A.B. said:

DogT said:

Here's a pic of the rect. and MC2, yours may be different colors and wires, this is the 69/70 version.

Click to expand...

For Robb's '73 model, the rectifier bolts directly to the frame without the bracket.

Click to expand...

This is what was confusing me... none of the holes in that area had the clearance for the rectifier to fit. I either lost an L bracket that it had been mounted on, or it had been mounted on the top bolt of the side cover mount. I ended up putting it on the top bolt of the side cover. There seems to be plenty of clearance and I don't think it matters which way it's pointed unlike the 2MC which needs to be pointing down.



I didn't notice that tab that was touching the frame. I can rotate it so that's not touching. Would it be better to make some kind of bracket or drill another hole... or leave it where it is?

Robb,
Are you running with points or electronic ignition?
Ying

Robb2013 said:

This is what was confusing me... none of the holes in that area had the clearance for the rectifier to fit.

Click to expand...

Slight revision!

1973 model :idea:

Your '73 model's rectifier should actually be mounted on the rear side of the plate! With the harness wiring to both it and the flasher relay (which also mounts to the rear of the plate) going through the hole (with grommet) in the frame to the rear of the oil filler cap.

YING said:

Robb,
Are you running with points or electronic ignition?
Ying

Click to expand...

It's set up with points right now. I will be converting it but probably later.

LAB already mentioned that the red/white and red/purple coming up from the bottom have no purpose and should be taped up. Does the same go for the 2 brown/blues and the green/white up on the top left and the double white and the green/white on the top right?

L.A.B. said:

Robb2013 said:

This is what was confusing me... none of the holes in that area had the clearance for the rectifier to fit.

Click to expand...

Slight revision!

1973 model :idea:

Your '73 model's rectifier should actually be mounted on the rear side of the plate! With the harness wiring to both it and the flasher relay (which also mounts to the rear of the plate) going through the hole (with grommet) in the frame to the rear of the oil filler cap.

Click to expand...

My bike is a 72 750. I think if the capacitor were mounted on the rear of the plate it might interfere with the fender. Is what you say true for just 73's or 72's also?

Robb2013 said:

L.A.B. said:

Robb2013 said:

This is what was confusing me... none of the holes in that area had the clearance for the rectifier to fit.

Click to expand...

Slight revision!

1973 model :idea:

Your '73 model's rectifier should actually be mounted on the rear side of the plate! With the harness wiring to both it and the flasher relay (which also mounts to the rear of the plate) going through the hole (with grommet) in the frame to the rear of the oil filler cap.

Click to expand...

My bike is a 72 750. I think if the capacitor were mounted on the rear of the plate it might interfere with the fender. Is what you say true for just 73's or 72's also?

Click to expand...

Sorry, I thought it was a '73 but yes probably the same for a '72 model.

The 2MC mounts on the front of the plate, the rectifier and flasher relay at the rear.

Robb2013 said:

red/purple

Click to expand...

White/purple (not red/purple).

Robb2013 said:

Does the same go for the 2 brown/blues and the green/white up on the top left and the double white and the green/white on the top right?

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Where is the ignition switch? That also has to be connected to brown/blue ([NU] to Ign/Sw. Terminal 1) you may find those two brown/blue wires need to be connected together?

A light green(?)/brown(?) [LG/N] and double white [W] would normally go to the flasher relay. Green/white [GW] would be for the R/H rear direction indicator.

L.A.B. said:

The 2MC mounts on the front of the plate, the rectifier and flasher relay at the rear.

Click to expand...

I can't find a flasher relay in my parts box or on the OB electrical page.

L.A.B. said:

Where is the ignition switch? That also has to be connected to brown/blue ([NU] to Ign/Sw. Terminal 1) you may find those two brown/blue wires need to be connected together?

A light green(?)/brown(?) [LG/N] and double white [W] would normally go to the flasher relay. Green/white [GW] would be for the R/H rear direction indicator.

Click to expand...

Ignition switch is wired... all the wires for it came out of the same grouping. Still not sure about those 2 brown/blue (or green) up on top left. Will remember the green/white when I get to the rear tail light etc. Still looking for the flasher unit.

Also, on the right side just below the oil tank there's a four pronged socket. I have a plug (fuse?) that fits in there but It had a hole in the middle for a securing screw that isn't in that socket. Know what's going on there?