Monza Square headlight parts.

[averydad]

The new switch/board is a translucent white color. I know this is the type that you told me is subject to failure from fuse overheating. But I`m going to hope for the best and perhaps it lasts a while, especially with my minimal use of the bike. The seller has several more switch/boards and I was thinking of buying a spare while it is available. Perhaps this would be insurance against a failure for me or some future owner.
I`ve run a 14 gauge blue wire to my horn and brake switch as instructed. I picked up a handful of bullet connectors and three generic inline fuse holders today. What amp fuses do you recommend ?

I spotted this warning light ....do you think this would be a good choice ?

http://www.ebay.com/itm/221041562074?ss ... 1438.l2649

I know it`s expensive but at this point I just want to get this project moving forward.

What I need now , if possible, is very direct instruction or a diagram of which color wires go where on my new board and headlight shell. I believe all my wires are color keyed as original save the purple wire which replaces the original grey. I have no wires leading to the handlebar switch at this time.
I do not want to pretend that I am an experienced motorcycle mechanic. I do have a great deal of experience in mechanical and cosmetic restoration of old British cars but am new to bikes. I`ve rebuilt engines and hydraulic systems.Replaced clutches and done interior restoration. Lucky for me up to this point my electrical experience has only involved replacing or repairing original wire harness`. I`ve never faced this level of electricl problem and am a little uneasy about my overall understanding of the job at hand.
Your patience and good will are very much apreciated !!
Rick

[DewCatTea-Bob]

" The new switch/board is a translucent white color. I know this is the type that you told me is subject to failure from fuse overheating. "

____ Right, that's the type that most easily melts !
The others, gray and I think brown, also can melt (where the fuse-holder is attached), but not as easily.


" But I`m going to hope for the best and perhaps it lasts a while, "

____ If you keep the fuse held TIGHTLY, and use a HL.bulb no stronger than 30-watts, then it likely won't melt.


" I`ve run a 14 gauge blue wire to my horn and brake switch as instructed. "

____ Actually, the 14-gauge is only useful to back as far as the horn,, from there over-to the brake-light switch, 16-gauge is quite good enough (and even 18-gauge would surfice).


" I picked up
three generic inline fuse holders "

____ Well if you're intending to use your new circuit-board exactly as it was originally intended to be, then I can only think of a good use for just one of those new fuse-holders you just got...
The stock wiring-system is designed with a fault which could allow the harness to get burned-up ! _ (I KNOW this cuz it has happened to me !)
To prevent such from occurring, a 30-amp fuse ought to be placed within the wire-lead that connects the neg.terminal of the battery to Ground.


" What amp fuses do you recommend ? "

____ Right-now, I don't recall exactly what rates Ducati used in their circuit-board, but I think it was 10-amp for the horn-fuse, and 8-amp for the other two. _ And those rates seem reasonable to me.


" I spotted this warning light ....do you think this would be a good choice ? "

____ NO WAY ! ...
First, it's not the type that was stock to your headlamp ! _ And second, look at that CRAZY RIP-OFF price (of over 50-bucks) ! ...
If it were well under 10-bucks, then one may care to try fitting that non-stock item into place in the HL.shell, but otherwise, it would be better to fit a LED.bulb, which is well under 5-bucks !


" I know it`s expensive but at this point I just want to get this project moving forward. "

____ Well if that's what you want but, you ought to make sure they'll take it back if you can't get it to fit well.


" What I need now
is very direct instruction or a diagram of which color wires go where on my new board and headlight shell. "

____ Sure.
Do you have all your main-harness wires that go into the headlamp terminated with those bullet-terminals you got & intended to fit into the circuit-board's terminal-plug/receptacle-holes ?
And do you see that that board has lettered-labeling for each of it's terminal-plug/holes, (such as 'B+' and 'SP' , etc.) ?
__ If so, then since you certainly already have your blue-wire & your white-wire ready to go, then
the White-wire plugs-into the circuit-board's terminal-hole/receptacle-slot that's labeled: SP ;
and the Blue-wire plugs-into the slot labeled as T+ .


" I have no wires leading to the handlebar switch at this time. "

____ Stock colors for those wires are: Black; Red; Green; Yellow.


" I`ve never faced this level of electricl problem and am a little uneasy about my overall understanding of the job at hand. "

____ Relax,, as this simplified-job (due to the 'circuit-board'), will be pretty/extra-simple for someone like you !


Tillater,
-Bob

[averydad]

OK....thanks for the vote of confidence Bob.
I`ve had a good day out in the garage. The luxury of a window air conditioner makes life sweet as it`s 95 here in Philly today !
The back of the Monza is done. Blue wire to horn then jumped to brake switch.
Old black wire run from horn back to headlight.
Black from brake switch to tailight.
All wires from control box (except those to battery) run in a sheath to headlight.
White wire from coil and green ground wire from coil mount to headlight also routed into the sheath.
It all looks very tidy.

Now in headlight I have the white hooked to "SP"
Blue to " T+"
Green grounded to mounting bolt.

Remaining are.....
Brown- from box
Red- back to battery
Purple (grey) - to box
Black - to horn
Black - to tail light

I`ve also got a supply of Black, Red, Green, and Yellow 18 gauge wire for the handlebar switch.
Ready for more instructions when time allows......

Your humble student,
Rick

[DewCatTea-Bob]

" Green grounded to mounting bolt. "

____ If you mean one of the two bolts that secures the headlamp, then that's okay. _ As I was going to tell you that you could do either that, or connect your green-wire (from the ign.coil-mount) directly to the black ground-wire of the HL.bulb .
____ Everything else you've stated you have got-done, is just as expected (so far) !
__ You posted-up that last post of yours coincidentally when I was just-about to add a pic.diagram (showing all the wiring-connections to the circuit-board) to my previous-post ! _ So now, I will add it to THIS post, instead.



" Remaining are.....
Brown- from box
Red- back to battery
Purple (grey) - to box
Black - to horn
Black - to tail light "

____ If the pic.diagram I've now posted doesn't make it clear as to which of your remaining wires are to be connected exactly where, then ask me for confirmation (of any wire-connection you're still unsure of). _ Cuz it's certainly possible to be confused about the PHYSICAL wire-connection locations, since the available/posted diagram-scheme/pic.drawing depicts it's 'physical' connection-locations only for the pre-1966 terminal-board.



" I`ve also got a supply of Black, Red, Green, and Yellow 18 gauge wire for the handlebar switch. "

____ Well 16-gauge would've been best but, since the run-lengths for those four wires isn't too long, (and Ducati also used 18-gauge),, then your 18-gauge wires ought to work well enough.
__ Do you have any idea of how those four wires are to be connected-up yet ?


Hopeful-Cheers,
DCT-Bob

[averydad]

Wow...... Looking at the diagram you posted I instantly recognized that this is the same thing I`ve been looking at for a month. In fact I posted it myself at one point.
I could`nt understand why you kept saying the wiring scheme between the older Monza and my version of the Monza were the same ! I now understand (sort of ) that while the diagram shows "wires" ....on my bike these connections are the same just handled via a circut board. Right ?

Anyway, I rushed to the garage and hooked up my wires as follows;

Black from horn to T-
Purple (grey) to C
Red to B+
Black from tail light to FT
Brown to S

One plug marked M remains unused.

I have put a longer bolt from the headlight ear and grounded the green wire direct to this point.

As for the handle bar switch....
My best guess is
Yellow to - FT
Black to - T-
Red to - T+
Green to - C

While the FT and T- locations have posts to attach the wires, I don`t know how I would hook up the other two wire to the board........??

How`d I do ?

[DewCatTea-Bob]

" I could`nt understand why you kept saying the wiring scheme between the older Monza and my version of the Monza were the same ! "

____ I've always meant to indicate that they are both the same 'ELECTRICALLY', (although not physically) !
__ In case you haven't noticed yet, I've already edited my previous-post so as to help clear-up this 'electrical'/'physical' - same/different issue.



" I now understand (sort of ) that while the diagram shows "wires" ....on my bike these connections are the same just handled via a circut board. Right ? "

____ That's correct... As all the circuit-paths (for both pre-66 & post-65 250M) are the same (electrically) !
__ It seems that when Ducati designed the newer/square headlamp (which isn't as large as the older-style Monza-headlamp), they then needed to devise a way to eliminate a fair-portion of the internal HL.wiring, and the circuit-board accomplished that to an extent.
However that change unfortunately also caused the new wiring-connection line-up to become different as well, (thus presenting a source of confusion due to the continued printing of the OLD physical-layout of the HL.terminal-board/wiring-connection diagram, instead of supplying an updated/1966 physical wiring-connection lineup for the new circuit-board, within the new/1966 owners-manual).



" hooked up my wires as follows;
Black from horn to T-
Purple (grey) to C
Red to B+
Black from tail light to FT
Brown to S "

____ That's all correct !
It's very-well that it seems you weren't left confused concerning the misleading depicted physical (wiring to terminal-board) connection-locations.



" One plug marked M remains unused. "

____ Right, (I don't know what that slot might've ever been intended for).



" I have put a longer bolt from the headlight ear and grounded the green wire direct to this point. "

____ That's okay... You can also ground the black ground-wire from the HL.bulb at that same point as well.



" As for the handle bar switch....
My best guess is
Yellow to - FT
Black to - T-
Red to - T+
Green to - C
How`d I do ? "

____ Sorry to say but, most-all of that is very-wrong... However, the horn-button's black ground-wire does indeed go to the 'T-' terminal-connection. - There's a screw-terminal/post under-there for that wire to be clamped into.



" While the FT and T- locations has a post the attach wires, I don`t know how I wold hook up the other two wire to the board........?? "

____ Well those other two handlebar-switch wires -(yellow & green) are for the High & Low beams, and THEY both connect to the terminal-posts provided for them on the HL.bulb-holder/socket-assembly !
__ The remaining red-wire is to be screw-clamped into the terminal-post provided for it on the rear-underside of the circuit-board.
I'll (soon later) post an indication of exactly which screw-post that should be,, but first, please tell me what the color of the wire is that goes to your parking-light bulb-holder (on it's HL.socket-assembly) ?



Tillater,
-Bob

[averydad]

Not sure what you`re getting at...... Are you asking me to figure out what wires SHOULD be there ? OK.... As of now I have no wires in place. I am enjoying trying to figure this out. Even though I`m having limited success. It`s hard to believe that Ducati never provided a proper updated schematic when they made a major change to the physical layout of the Monza wiring ! No wonder so many of these bikes seem to have butchered or rigged wiring. How many owners would be able to figure this out once they had a problem or failure with out any reference material ?

In looking at the somewhat useful and somewhat confusing diagram I have.... I would say on one side, that the parking light (8) shares a ground with the headlight (9) , shown as a black wire. The second wire appears to be a grey wire to provide power from the comutator switch (11). The switch looks to be fed by the yellow wire which would attatch to the terminal post at the FT location on the circut board....??
So does the yellow wire go direct to the lamp from the FT terminal post in this later scheme ?

That`s my best guess, although I`m glad I have no money riding on this idea !

[DewCatTea-Bob]

" Are you asking me to figure out what wires SHOULD be there ? OK.... As of now I have no wires in place. "

____ I'm sorry, at the time I had THEN forgotten that you didn't yet have any wire (of any color) connected to the parking-light bulb-holder.
We'll continue-forthward as if that wire will be a (short length of) gray-wire, (as the old Ducati diagram appears to depict.



" I am enjoying trying to figure this out. "

____ That's great, as that's part of reward of having a Duke-project to complete !



" It`s hard to believe that Ducati never provided a proper updated schematic when they made a major change to the physical layout of the Monza wiring ! "

____ I guess Ducati assumed that the old pre-66 scheme-diagram was close enough. _ But most of us would agree that the Monza/Sebring diagram should've been updated so that it would then be BOTH electrically and PHYSICALLY correctly laid-out. _ As that no-doubt would've then helped many avoid getting hopelessly lost and-so then choose to start-over from scratch with some concocted wiring-scheme of their-own.
__ I'm sure I've never seen or heard of any diagram which more accurately represented the 1966-version of the electrical-system of those narrow-case Duke-models.
However for the newer wide-case versions of the Monza & Sebring models, their scheme-diagrams were then finally updated.



" No wonder so many of these bikes seem to have butchered or rigged wiring. How many owners would be able to figure this out once they had a problem or failure with out any reference material ? "

____ You're right, most average-owners would not be electrically-savoy and thus much more dependent on accurate PHYSICAL lay-out info, in order to make much good sense of it all.



" In looking at the somewhat useful and somewhat confusing diagram I have.... I would say on one side, that the parking light (8) shares a ground with the headlight (9) , shown as a black wire. "

____ That's a correct deduction, as that pre-66/non-USA HL.bulb-socket set-up uses that one wire to ground both light-circuits to the headlamp-shell.
However on the 1966-type/USA-version of the Monza/Sebring-models, a black ground-wire was used to connect it's sealed-beam's ground-terminal (routed back) to the ign.coil's mounting-bracket location on the frame,
which was an important improvement (since the fork-ears don't always stay fully grounded).



" The second wire appears to be a grey wire to provide power from the comutator switch (11). "

____ That's correct, that wire-connection provides battery-power (indirectly through the reg.box), to the small bulb-holder when the light-switch is in it's parking-light position.



" The switch looks to be fed by the yellow wire which would attatch to the terminal post at the FT location on the circut board....?? "

____ That's a commonly-deduced seemingly logical deduction (when one only looks at just the light-switch itself [and not also the FT-wiring going-back to the tail-light] ), but that's not correct however ! ...
That connection you're referring-to is actually for the tail-light, as it has to be able to become powered regardless of whether that light-switch is set to be fed input-power from the key-switch OR more directly from the battery (when in park-mode).



" So does the yellow wire go direct to the lamp from the FT terminal post in this later scheme ? "

____ This question doesn't make understandable-sense to me. _ So if it's still a valid question for you, then please try again using different wording, (as I'm not sure what "lamp" you're meaning to refer to.
__ If you were referring to the yellow-wire from the handlebar-switch, then that wire (along with the green-wire), runs DIRECTLY to the HL.bulb-socket (with no connections on the circuit-board) !
__ Now if your FT/taillight-wiring was ALL yellow (instead of partly black), THEN I'd think that that's the "lamp" you're actually referring to !?
But in either case, your question-wording still leaves me somewhat confused.


____ I've now edited & added the underside-view of your picture of your circuit-board, so as to indicate where the gray-wire (to parking-lamp), and the red-wire (to handlebar-switch), are to be connected at. _ While the red-wire is obvious, I'm afraid that the depicted gray-wire may be a bit hard to see against the similarly-colored background, (so look closely for it).
__ When attaching the wires to their screw-clamp terminal-posts, rather than inserting the plain/bared wire, it's best to first 'tin' the wire-tips (as Ducati-themselves had done), with some solder (or better-yet, silver-solder), so that a more solid connection will last & perform better.


DUCATIly,
-Bob

[averydad]

Hello once again,
Sorry for the confusing previous question. It was 1:00 AM and I guess I had been staring at that diagram far too long.
Moving on....I`d like to review what`s left to get this machine on the road !!

My main harness seems to be all set, both wired to the bike and to the headlight / board.

The handle bar switch needs to be wired as follows;
Black = to T- lug on board.
Red = direct to board lug as you kindly have shown me.
Green = to headlight socket
Yellow = to headlight socket

The park light wires go as follows;
Black = to ground at headlight ear (joined with wire to coil mount)
Grey = to lug on circut board as shown in your last post.

What remains as I see it, is the switch end on the handle bar wires
and the warning lights.

If you could kindly translate the schematic I posted on the switch box, I think I`ll have that part licked.

As for the warning lights I now believe I understand....
The high beam light is a festoon bulb mounted to the circut board that simply shines throught the lens in the headlight when lit.
The parking light is another festoon style bulb that illuminates also through a lens in the headlight shell.
That leaves the ignition warning light. Can you please explain what wires I need to connect for this to work.

Looks like I`m in the home stretch ! Once I solve the last few questions posted above, I just need to purchase the bulbs and fuses. By luck I followed your thread regarding the 160 Monza Jr. headlight parts diagram I had posted. In that thread a fellow member mentioned the ducatimeccanica.com site. There I found a parts picture and description of the 1966 250 Monza headlight. It`s even marked as "USA" version. Wish I had seen this a month ago.

http://www.ducatimeccanica.com/parti_di ... io0168.htm

This gives me the size and wattage of the festoon bulbs as well as the fuse amperage as follows..... ( 378) High beam bulb 1.5 Watt 6x29, (380) Park light bulb 3Watt 6x38.
Fuses (345) are listed as 25 amp for all three.
My next challenge is to track down these items. Especially the fuses as at least I believe I could run with out the bulbs if the search took too long.
Any leads on the bullet type fuses and festoon bulbs ?
Well I can`t wait to get home this afternoon and back to work on the bike. I have my new battery on the charger and ready to go.
I can almost feel the wind in my face !

Cheers

[DewCatTea-Bob]

" The handle bar switch needs to be wired as follows;
Black = to T- lug on board.
Red = direct to board lug
Green = to headlight socket
Yellow = to headlight socket
The park light wires go as follows;
Black = to ground at headlight ear (joined with wire to coil mount)
Grey = to lug on circut board "

____ All the above is correct.



" If you could kindly translate the schematic I posted on the switch box, "

____ I'll soon post an edited-pic of that (like I did with the board-pic).



" As for the warning lights I now believe I understand....
The high beam light is a festoon bulb mounted to the circut board that simply shines throught the lens in the headlight when lit. "

____ Well No & yes...
The bulb which is held by the circuit-board is actually for the charging indicator-light !



" The parking light is another festoon style bulb that illuminates also through a lens in the headlight shell. "

____ Well yes but barely noticeable there (atop the shell), as it's holder is way-down along-with the HL.bulb-socket.



" That leaves the ignition warning light. Can you please explain what wires I need to connect for this to work. "

____ I sorta corrected you on this once before,, you must have been confused with a w-c.model, as no n-c.model has ever had an "ignition warning light" !
__ The remaining warning-light is the (red) 'HIGH-beam indicator-lamp'.
And for that a relatively short length of 20-gauge will connect it to the high-beam circuit on the HL.socket.



" Fuses are listed as 25 amp for all three. "

____ I recommend using fuses under that amount ! _ Rather 10-amp to 20-max.



" Any leads on the bullet type fuses and festoon bulbs ? "

____ Try your longest-established local VW-dealer.


____ Don't you plan to install one of those new fuse-holders you recently got ?
I really recommend that you install one (with a 30-amp fuse) between the battery's neg.terminal-post and the point where it's grounded to the frame.
__ And I recommend that you ground the battery (with a 12 or 14 gauge green or black wire), to the same point where you've already grounded your green-wire from the headlamp.


Duke-Cheers,
-Bob