Systems to Brighten Dim Lights on Alt.Powered models

[DewCatTea-Bob]

" Can you explain the last diagram ? "

____ I'll soon explain some more about it within it's own post, by reEditing that post, (as I've already done with a couple other (so noted) posts within this thread).


" was there a stator configuration that has the 2 coils and only 2-wires ? I just opened-up a older 4-speed engine and that is what I found ? "

____ There sure was! _ (You must have missed my other posts about such.)
I remember when that was the only type there was! _ As far as I know, the 2-power-coil / 2-wire alternator was the only type on DUCATIs until the Mark-3 was required to have a brake-light in late '63.
__ What color are the two wires on yours?
The Monza model had 2-yellow wire-leads, one to each (identical type) coil. _ The Motocross & Mark-3 models had a yellow-wirelead to the ign.power-coil & a red-wirelead for the lighting power-coil.
All 3 types of the power-coils's opposite lead-ends were grounded to their stator.
I recall being upset when I first learned that Ducati replaced their 4-pole (40-watt) alternators with the 6-pole (60-watt) versions. _ As the new stator didn't seem (at the time) to be as easy to convert for 12-volt system.


Stay Tuned,
DCT-Bob

[ajleone]

Bob,
The wires look to be black and red on the 2-wire dual-coil stator. The stator is out of a 4-speed engine, serial number 84713, which is either Scrambler, Monza, Diana but not a MK3 (no M3 stamped on the engine case).

Thoughts on the wiring ?
Tony

[DewCatTea-Bob]

" The wires look to be black and red on the 2-wire dual-coil stator.

____ While I've never owned one with those colors, I have indeed seen (about 3) MONZAs with the 1-red & 1-black colored wire-leads! _ I don't know the reason for that -(in place of the standard pair of yellow-wires), it could be that replacement-stock came with those odd colors. _ I've always wondered what the actual story is on that !


" but not a MK3 (no M3 stamped on the engine case). "

____ The (early) Mark-3 models did not come with the 'M3' stamping, until late 1965, (for the purpose of sorting Mark-3s from the then new Mach-I -['M1'], I believe).


____ (I think that Tom Bailey could better answer both of these mysteries.)


Hopeful-Cheers,
-Bob

[bettyann]

Dew cat Tee Bob

I think your latest diagram of 6v28 system, using two bridge rectifiers 1 with 4th wire & white, and 1with the4th wire and red. So both of these out puts go to the battery. What would the output amps to the battery, lights off, and lights on approx?
That's perfect, Mag type starting w/o need of a battery,and battery powered brighter lights. I think that would simplify, the rest of the wiring harness. Could those rectifiers be put in the headlight shell without overheating them? This would be perfect for all of my dukes ( bronco too). But not for harder kicking Sebring ! I'm gonna start working on this. Thank You Capt Paul

[DewCatTea-Bob]

" So both of these out puts go to the battery. "

____ Well, both outputs are meant to CHARGE the battery whenever RPMs are above the break-even point, and HELP the battery run the loads whenever RPMs are below the break-even point, but it's best that both outputs aren't wired directly to the battery.
To keep the battery from running-down through the rectifier, the WHITE-wirelead ought to be isolated with the stock ign.switch, and the RED-wirelead ought to be left unconnected until the lights are switched-on (as Jap-bike light-switches automatically do!).


" What would the output amps to the battery, lights off, and lights on approx? "

____ Well that -(the charging-current), is directly dependent on RPM ! _ I've been basing such figures on Ducati's claim that these (4-pole type)*coils of their's are good for "40 watts", (which really isn't fair to state without also stating the RPM at which the amount of watts is produced).
A properly hooked-up ammeter would answer that question best, but (with a 6-volt battery), I wouldn't expect more than 2-amps from the WHITE-output, nor more than 6.5-amps (total max) from the RED-output. - (That's 2 + 4.5 amps.)
I've used ammeters on all my best projects,, and with these 4-pole alternator set-ups, ya hardly ever see the battery draw much more than 1-amp, (except for a short time when a like new but discharged used-battery is first subjected to the charging-current).
_*Note: I believe the reason that the "28watt" alternator is rated at only 28-watts (instead of 40-watts), is because part of that power-coil's power-juice is deverted away from the lighting-circuit (to be shared with the battery).


" Could those rectifiers be put in the headlight shell without overheating them? "

____ That would depend on the rating of the rectifiers you choose... If you connect units with the minimum-requirement (of 6-amps), then overheating could be a problem (after a long period of high-RPM running with lights on). _ However units that are made to handle 25-amps, would likely be quite okay for that.


" This would be perfect for all of my dukes ( bronco too). "

____ I don't know about that, for a non-OHC model.
THANK-YOU for not calling your DUKEs "bikes" ! - (Like most the young-guys do.)


DUKE-Cheers,
DCT-Bob

[bettyann]

Dew cat Tee Bob

I misunderstood the top of your diagram, had the two red paths go to a wire to the battery w/out a switch is the way of that path.
Now I'm ready for that 40w 4speed monza alt to 12v modification.Tell me more.
Thank you Capt Paul

[DewCatTea-Bob]

" I misunderstood the top of your diagram, had the two red paths go to a wire to the battery w/out a switch is the way of that path. "

____ That's quite reasonable, cuz as I had meant to convey, I didn't properly finish that diagram's scheme due to frustration with the ('Imaging') program I used to make it! - (Everytime I thought I was finished and would then close the program, part of my work would then simply disappear and/or get screwed-up! _ [And I really don't like to have myself so associated with less than perfect work!] )
__ The switch (in yellow) was intended to show that EITHER the WHITE-wirelead OR the RED-wirelead gets connected (somewhere-down-the-line) to the battery's positive pathway.
The two depicted red-lines from the two rect.blocks ought to be colored orange-with-white (for left-unit), and (for the right-unit) orange-with-red,, (but I need a better program to show that!).


" Now I'm ready for that 40w 4speed monza alt to 12v modification. "

____ That's relatively simple (with the 6-pole stator)! ... Ya just unground the pair of coil-winding lead-ends -(which are already soldered together) and then insulate them from ground.
But with the older 4-pole version, it's best that ya go-ahead & add another pair of wires (to be connected to the ungrounded lead-ends).
__ Is your intended 4-pole stator with two yellow wire-leads?
Got and pix?


Continued-Cheers,
-Bob

[DewCatTea-Bob]

____ Well fellas, I thought maybe things might turn-out better if I worked with larger item-depictions, but I still had much trouble with the Imaging-program screwing-up my highly detailed details!
I've tried to clean-up the program's splatter-noise as good as I could get it... For example, in the areas where I HAD perfect ground-symbols, I did not bother to clean-up the all the white-spec noise, nor fix the damage to those symbols ! _ That sort of problem tries to occur all over the whole drawing!
The white and red wire/lines stayed their original color well enough, but as ya can see, the red_&_green wire/line insists on not staying as intended, especially with it's vertical-section !
So while not nice to look at closely, I hope it helps ya in some way better than my last attempt!
____ Since the important areas of the more-complete diagram-scheme have ended-up so poorly detailed, I've included an expanded-view of just the alt.coil-section plus the two rect.blocks area, (so as to better display the wire-lines and all their connections, [without so much added noise & loss of detail]!).
The unconnected terminals (in the upper-rights) of each rect.block, are the positive-outputs (which are shown connected to red wire-lines in the other view-drawing).


Better-Cheers,
-Bob

[bettyann]

Dew cat Tee Bob;
Today radio Shack is advertising a 25A 50v full wave rectifier for $3.29 ea.
Is this the one to buy? If so I'll buy 3 or 4,cool?
Capt Paul

[DewCatTea-Bob]

" Today radio Shack is advertising a 25A 50v full wave rectifier for $3.29 ea.
Is this the one to buy? "

____ Well with those specs,, while the 25Amp is considerably MORE than required, the "50v" may not be sufficient (for when all loads are suddenly disconnected during high-RPM).
If that particular rect.block has a nice mounting-hole (through it's center), and the "50v" actually stands for 50-volts 'RMS', then it's an okay-choice.
But if the "50v" actually means 50-volts 'PIV', then a better choice would be a similar unit with 10A 100v specs, which ought to be cheeper !
__ The far more popular '25A-200PIV' rect.block (with center mount-hole), ought to be about the same price, and is the unit which I always preferred !


Better-Cheers,
-Bob