250 Alternator Wire Source

[DewCatTea-Bob]

" Plus the language of electrics is not my native language. "

____ Anyone who's had a high-school science-class ought to understand most electrical-terms related to old stock DUCATIs.


" I figured that since I was there, I'd go ahead and add the 3 wire setup like you suggested. "

____ I've actually never suggested any "3" wire set-up myself, (4-wire is better),
however it's a good-idea to UNground the original pair of stator-winding lead-ends from the stator-plate while you can still easily get-at those wiring-connections of your alternator. _ That way, you could get more power out of the alternator (with a non-stock rectifier-unit), and by using the 3rd wire to also extend the other/internal lead-ends of the stock alt.power-windings to the outside, from within the motor as well,, you then provide for yourself other possible options which you may prefer later (without having to repeat the internal wiring-work you're already doing).
And yet, you can still wire-up your electrical-system to be the same-as-stock -(electrically), by re-grounding those alt.power-windings by connecting your additional/3rd-wire's outer-end to any place you choose, (like at one of the bolts which hold the original black-box to the frame, [as was originally done with the stock green neg.battery-cable] ) !
__ Have you considered putting your chosen computer-cable inside an oven for a couple of hours at 200/225 degrees, to make sure it can handle that high of temperature?


DUKE-Cheers,
-Bob

[tricolormonster]

All my computer cables seemed to be 16/3, so I bucked up and bought some cable.

I solved the problem with a quick trip to my local Fry's Electronics. I purchased a 14/3 heavy duty 105°C Oil resistant outdoor cable. Totally looks the part and is nice and fresh. Plus I have tons left for the future bikes I have tucked away.

I also added some colored shrink wrap for strain relief and soldered it all together.
Another bit of 125°C black shrink wrap around the bit inside the engine for added measure and cut it just below where it emerges from the engine. I will refit my flywheel tonite.

thanks for all the help so far...

stu
Rewire Pic ** the green will go under the plates when installed**

photo.JPG

[DewCatTea-Bob]

" All my computer cables seemed to be 16/3, so I bucked up and bought some cable. "

____ That seems to have defeated the idea of using a surplus computer-cable (like so many of us have!).
And actually, the 16-gauge wiring would've been just fine, however the 14-gauge is better if ya can still fit the needed number of 14-gauge wire-leads through a cable-conduit that's also thin enough to fit through the DUCATI's cable-ports.


" I also added some colored shrink wrap for strain relief and soldered it all together.
Another bit of 125°C black shrink wrap around the bit inside the engine for added measure and cut it just below where it emerges from the engine. "

____ Thanks for the pic Stu, (looks like you could use that now unused grounding-point tab to help tie-down your green wire to keep it away from the crankshaft). _ Everything looks & sounds like you've done some very good work on this project of yours !
If I had ever found any such large-sized shrink-wrap tubing, I would've used it within the motor too,, probably instead of the extra-added conduit-covering which I'd use for that added/non-stock bit of extra protection ! ...
__ For many of my own home-made alternator-cables, I'd use nylon-reinforced clear fuel-line, and for added protection for the length of it within the motor-case, I'd cover that fuel-line with another (thinner) conduit-covering which I'd strip-off from a row of special multi-conductor phone-company cable which I already happened to have. _ It was silver in color and said to be more resistant to UV-light damage, (although not important within the motor), and I'd usually also use that silver plastic-coating conduit over the more weather-exposed section of my fuel-line conduit as well.
__ However, all my home-made alt.cables would house (at least) four 18-gauge (if not 16-gauge) wire's of colors which were logically chosen. - (BTW, the 4th wire [in this type of case] was for keeping separate the power-outputs of the stator's pair of [originally] grounded lead-ends.) _ And I myself thought it neat to be able to see their individual wire-colors through the clear fuel-line conduit which I (logically) preferred for the job.


DUKE-Cheers,
-Bob

[DewCatTea-Bob]

____ Stu has been making recent progress with his chosen method for modification of his n-c Monza-type twin wire-lead alternator...
Concerning his project started in this thread, he recently PM.ed me instead of continuing-forth here, I gather because he couldn't get his quite nicely done wire-connection scheme-diagram (presented in 'tif' form) to post here on this w.site.
So since his project is quite worthy of being posted, I'm now transferring that which he had sent to me, to be noted here as well ! .....
__ By Stu...

I have a question about the electrics on my 64 Monza if you don't mind.

I wired the alternator up with the 3rd wire when replacing the wire, and brought it out of the engine and grounded it at the earth for the Battery and Regulator.

My question is this, Do I still need the ground from the regulator?
Everything else is still the stock 6v system and Regulator.
Should I ground the Alt wire to a different point on the chassis?

I've modified a schematic to illustrate my question.

thanks very much.

stu

____ My reply-answer back to Stu was (in effect) that his good work was just fine and all his displayed ground-connections were just as they ought to be done !!
Although I realize now that I did overlook answering his last (following) question ...


" Should I ground the Alt wire to a different point on the chassis? "

____ No, the stock location (where the battery grounds at) is best,, however, it's a good idea to include a 16Ga.wire from that same point & going on-up to the headlamp-shell, (to ground the shell better), mainly so that the ground-terminal of the headlight-bulb doesn't have to depend on just a common-ground circuit (back-through to the battery) !

____ While I've left Stu's included scheme/display just as it was sent to me, I've converted it (from tif to jpeg) so that it can now be posted here (below).
It seems that he took a copy of a Ducati n-c wiring-diagram and (besides showing just the pertinent portion of it, unaltered), has correctly altered it to nicely show his (modified-version) wiring-scheme, which he has intended for his Monza-project !
__ I highly recommend that everyone who doesn't intend to use an alternate plan (which may or may-not be more useful), for their own n-c twin alt.wire-lead charging-system,, follow this same plan/method, whenever they need to replace the stock (disintegrating) alt.wire-leads in their motor ! _ Cuz not only does this plan allow for keeping the original charging-system otherwise stock, it also allows for replacing the old heavy stock black-box with the more modern w-c type rect.reg.box-unit,, as well as provide convenient possibility for many other alternative charging-system set-ups !!


Nice-Cheers,
-Bob

[DewCatTea-Bob]

____ At this point, I realized that we may have an opportunity to learn which alt.stator power-winding is which, since Stu's alt.stator happened to be one of those of the type which have one Black & one Red alt.stator wire-leads, instead of the (more common) pair of Yellow wire-leads...
With the standard alt-stator versions which have their two separate power-windings connected to alt.wire-leads which are both Yellow, there's thus no way to tell which one of the pair is the one which happens to be producing a positive power-pulse at the very-same point in time when the ign.points open. _ However with the uncommon alt.stator versions which have the separate colored alt.stator wire-leads, once it's learned which of the two (Red or Black) is the one which happens to provide the extra-DC power-pulse for assisting the battery with the ign.load, then we can also thus realize which alt.power-winding is the useful one, of those (more common) alt.stators which have just Yellow alt.wire-leads, as well ! _ (Since we have Stu's picture showing exactly where the stock Black and Red wire-leads were connected to his shown alt.stator's power-winding tip-ends.)
__ So I sent him my email/inquiry (below), in an attempt to learn if it's still possible for this information to be recovered (from his project).
Following my email to him, is his own reply-email.....

I HAVE A CONCERN WHICH COULD BE OF HELP TO OTHERS IF NOT YOURSELF AS WELL...
WHEN YOU REPLACED YOUR ORIGINAL-ALT.CABLE'S WIRE-LEADS, ARE YOU ABSOLUTELY-POSITIVE THAT YOU REPLACED THE ORIGINAL BLACK-WIRE WITH YOUR NEW BLACK-WIRE, AND THE ORIGINAL RED-WIRE WITH YOUR NEW WHITE-WIRE (and therefore couldn't have at-all possibly gotten those two reconnection tasks mixed-up) ? _ IN OTHER WORDS, DID YOU REPLACE JUST ONE WIRE AT A TIME (or, performed both tasks at once, thus allowing the possibility of a color connection switch) ?


By Stu...
" Well i went back to look at the pictures in the thread and I'm pretty confident that I did them right. Black to Black,White to red and the new green leg.

So how are they supposed to plug into the regulator? Does the order matter?
what would be the result of hooking them up backwards? "

" So how are they supposed to plug into the regulator? Does the order matter? "

____ No, the exact order does not matter, (unless perhaps one of your black-box's two internal power-diodes has gone-bad) ! ...
Your black-box ought to have two Yellow indicator-squares (on the strip of 6 colored-squares), and either Yellow receptor-terminal can equally accept either colored (Black or Red [or Yellow]) alt.wire-lead !


" what would be the result of hooking them up backwards? "

____ Well with the stock black-box -(the so-called "6volt regulator"), there's really no difference, thus there's no way for the two separate alt.wire-leads to be connected (into the bb.unit's Yellow-inputs), "backwards" ! _ (Since 'AC' is 'AC' !)
__ However for more logical, (although less automatic), charging-systems,, there does indeed happen to be a 'difference' ! ...
That's because while one alt.wire-lead (Black [or Yellow#1]) may happen to be providing a useful Positive power-pulse output, the other alt.wire-lead (Red [or Yellow#2]) then happens to be providing an unused (and therefore useless) Negative power-pulse output !
And also, during the next half-cycle of the alternator's AC-output, the other alt.wire-lead (Red [or Yellow#2]) would then be providing a useful Positive power-pulse output, while the other alt.wire-lead (Black [or Yellow#1]) will be providing an unused/useless Negative power-pulse output !
__ Now while both Positive-outputs are "useful" for the stock battery-charging circuit-system, ya can now understand that only ONE of those two Positive-outputs can happen to provide a convenient Positive-DC power-pulse at the particular time when the ign.points are set to open (and create the ign.spark) ! _ So knowing WHICH alt.wire-lead is the one which happens to provide that, could be important to realize, for use in a more efficient type of charging-system.
__ Again however, with the stock-system, the two Positive-outputs are blended, so thus it doesn't matter "which is which" .


Dukaddy-DUKEs,
-Bob