250 N/C Wiring

Ducati single cylinder motorcycle questions and discussions, all models. Ducati single cylinder motorcycle-related content only! Email subscription available.
Moderator: Morpheus

Moderator: ajleone

willyg
Posts: 18
Joined: Tue Oct 12, 2010 8:05 am
Location: california

Re: 250 N/C Wiring

Postby willyg » Sun Oct 24, 2010 11:36 pm

I am going with 12 volts. I just makes sense, as I don't have bulbs, battery or even a wiring harness yet. I have been looking over other posts about how to do it. I appreciate everyone's help with identifying and wiring up my DUKE.

By the way, the cycle swap meet in Long Beach was worthless. Plenty of Harley stuff and bicycles but nothing Ducati. I'll keep looking on ebay and this forum.

Regards,
Will

DewCatTea-Bob
Posts: 2897
Joined: Sun Nov 01, 2009 10:53 am
Location: Near SE side of Lake Michigan

Re: 250 N/C Wiring

Postby DewCatTea-Bob » Mon Oct 25, 2010 12:13 am

" the cycle swap meet in Long Beach was worthless.
nothing Ducati. "

____ Right, if I'd thought there was a fair chance of finding a 60-watt n-c alternator there, I would've advised you to get one.

____ In order to get the maximum power out of your 4-pole type alternator for a 12-volt system, you will need to add a 4th wire-lead,, with it then connected to the (dual-coil)- stator's lighting coil-winding's lead-end -(which is normally grounded to the stator-plate).
Have you seen and are you okay with that type of modification, (as I believe I've already told of, within another thread) ?
__ I've not yet ever told of modifying the 4-pole stators so that their two (otherwise) separate coil-windings are simply connected in series, (for a 12-volt electrical-system conversion), because THAT rewiring-method then requires a 12v voltage-regulator, (and also, that's a simpleton-system that most others would already think-of on their own, anyhow).

. . .

____ For anyone else who's got a stock-wired '40-watt' alt.stator, and just wishes to simply retain a 6-volt system but with a battery added,, ya could just connect it's Red -(lighting-coil's) wire-lead to a (half-wave)- diode and then to the battery's Pos.terminal, so as to keep the battery charged, while also running a battery-powered type of ignition set-up.
The power-output of the other alt.power-coil should then have it's two (White / Yellow) wire-leads connected to a (full-wave)- bridge-rectifier, with it's Neg.terminal connected to Ground and it's Pos.terminal connected to a switch (to the B+ line), so that it can be switched-ON whenever the lights are turned-on, (so as to then help keep the battery charged while lights are running).
__ This simple charging-system set-up, (which ignores 1/4th of the alternator's total available-power, [yet utilizes more alt.power than the stock-system!] ), doesn't really need any regulator since it's not going to produce more power than a (normal-sized) battery can manage to keep under control (during normal riding). _ However, running for extended periods at high-RPM with the lights off, could possibly cause the battery to boil-off it's water-level at a much increased rate.


Dukaddy-DUKEs,
DCT-Bob
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob

willyg
Posts: 18
Joined: Tue Oct 12, 2010 8:05 am
Location: california

Re: 250 N/C Wiring

Postby willyg » Wed Oct 27, 2010 7:37 pm

After reading over everything multiple times I am left rethinking my decision to convert to twelve volts.
I plan on using the bike for mostly city riding and a few 100 mile rides. With this in mind, it seems that keeping the DUKE 6v is fine. It doesn't need to produce more power then it can consume. I do need new bulbs but 6v only cost a dollar or two more than 12v. I think the best plan for me is to wire her up close to stock, but with a modern bridge, battery, and connectors and see how she runs. I am going over some of the earlier posts about brighting headlights and develop a schematic, then build a harness and wire it up.

The previous owner told me there might be something wrong with the head. I have yet to confirm this.

There is also an aluminum shim under the cylinder that I need to investigate. Maybe put there to lower compression to aid in starting?

Regards,
Will
You do not have the required permissions to view the files attached to this post.

DewCatTea-Bob
Posts: 2897
Joined: Sun Nov 01, 2009 10:53 am
Location: Near SE side of Lake Michigan

6-volt vs. 12-volt Charhing, for Best Electrical-System

Postby DewCatTea-Bob » Thu Oct 28, 2010 5:53 am

" After reading over everything multiple times I am left rethinking my decision to convert to twelve volts. "

____ Sure wasn't meaning to steer you away from going the 12-volt path !


"I plan on using the bike for mostly city riding and a few 100 mile rides. With this in mind, it seems that keeping the DUKE 6v is fine. "

____ As far as the difference between 6 & 12 volt charging goes, there would only be a slight difference in the RPM needed to actually begin any actual charging of the battery...
As a 6-volt battery's std.volatage-level would be able to feel charging-pokes from the alternator's voltage-peaks, at a slightly lower RPM than a 12-volt battery would,, as the RPMs climb, from a non-charging to a charging amount of alt.power-output.
So while that may seem like a worthwhile-bit of an advantage for prefering to go-with the 6-volt choice, it's not really very critical for normal (non-constant low-RPM) riding. _ Because a 12-volt battery won't begin to act as a load (and begin consuming alt.power-juice) at the same lower RPM, thus allowing the alt.power to fairly quickly build-up from the 6v to the 12v level and therefore tends to reduce the otherwise seemingly quite noteworthy advantage, (which is actually only a slight one). _ (Keep in mind that a battery that's able to receive any CHARGING-juice is also a 'load' that's partially wasting the charging-system's power-juice, since unlike a capacitor, the battery can't give back everything it has taken !)
__ And from the other point of view, a 12-volt battery system will not as likely make any use of a voltage-regulator.


" I think the best plan for me is to wire her up close to stock, "

____ Unless you get a stock-type alternator, that's not going to be exactly possible. _ But I'm sure we can get you set up with a fairly-good workable system, using the alternator you've got.


" I am going over some of the earlier posts about brighting headlights and develop a schematic, "

____ While those posts (in another thread) tell of adapting a battery for use with another system which uses the type of alternator you have, I don't think any cover your particular combonation of parts.
So I'd like to offer you some additional guidence for your particular project.


" There is also an aluminum shim under the cylinder that I need to investigate. Maybe put there to lower compression to aid in starting? "

____ Right, as that could well be a rare 3mm-cyl.shim that was used for women & smaller teens, who were otherwise intiminated by the "big-250s" (back then).
Or it could be a special home-made spacer for adapting a non-standard piston.
Care to get that investigated soon?


Hopeful-Cheers,
-Bob
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob

willyg
Posts: 18
Joined: Tue Oct 12, 2010 8:05 am
Location: california

Re: 250 N/C Wiring

Postby willyg » Thu Oct 28, 2010 7:31 am

"So I'd like to offer you some additional guidence for your particular project. "

Thank you. I very much appreciate your guidance so far, and am grateful for any and all additional help you are willing to offer.

If twelve volts is the way to go, then I am all for it. I don't mean to waffle, I am just new. I am willing to try modifying the alternator. Not exactly clear how to do it. I have limited experience soldering. I have worked on some old guitars and amps. Not exactly the same thing as an old Ducati.
I definitely will need some help with the physical connections, once I draw up a schematic for how to wire it, i.e. types of connectors to use, where to run them, what type of battery I need. I do have an old red top coil, but it looks to be mounted backwards. I am not sure how to test it. Without having much to go by, I am sort of at a loss.

"____ Right, as that could well be a rare 3mm-cyl.shim that was used for women & smaller teens, who were otherwise intiminated by the "big-250s" (back then).
Or it could be a special home-made spacer for adapting a non-standard piston.
Care to get that investigated soon?"

I would like to get into that, but I am reluctant to tear into her further without addressing the current wiring situation. That project should probably be under a new post anyway.

Regards,
Will

DewCatTea-Bob
Posts: 2897
Joined: Sun Nov 01, 2009 10:53 am
Location: Near SE side of Lake Michigan

Re: Modification of the 40-watt Alt.stator's Lighting-Coil

Postby DewCatTea-Bob » Fri Oct 29, 2010 12:50 am

" I am willing to try modifying the alternator. Not exactly clear how to do it. "

____ The alt.stator power-coil that has the Red wire-lead connected to one end, will not only need that wire-lead replaced (due only to age), but will also require a second wire-lead to be connected to the opposite-end of that power-coil's winding, where it's lead-end has been grounded to it's stator. _ So you'd have to un-ground that lead-end and connect it to a 16Ga wire (preferably with fine-stranded copper, and Red/Green insulation).
__ Have you looked-over your stator to see if you think you could handle that modification ?
That piece of work would be the most difficult operation, to get your new electrical-system completed.
__ The AC-output (of that lighting power-coil's two wire-leads) would then need to be full-wave rectified by a 10 or (25-amp) bridge-block, of which it's DC-output should then be switched so that it's only turned-on when the lights are running off the battery.
____ The other alt.stator power-coil -(meant for ignition & brake-light), would also have to have it's Yellow & White wire-leads connected to another separate bride-block, so that it's full-wave DC-output could then keep the battery charged and run a 12-volt battery-powered ignition-system.

____ Please let us know where you're at with this,
and what else concerns you.


DUKE-Cheers,
-Bob
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob

willyg
Posts: 18
Joined: Tue Oct 12, 2010 8:05 am
Location: california

Re: 250 N/C Wiring

Postby willyg » Tue Nov 02, 2010 5:06 pm

"So you'd have to un-ground that lead-end and connect it to a 16Ga wire (preferably with fine-stranded copper, and Red/Green insulation)."

---Do I leave the end ungrounded? Do I run the red/green wire back up through the slots in the stator? Will heat-shrink work to protect the wires through the engine case?

"The AC-output (of that lighting power-coil's two wire-leads) would then need to be full-wave rectified by a 10 or (25-amp) bridge-block, of which it's DC-output should then be switched so that it's only turned-on when the lights are running off the battery."

---So I need to get two bridge block rectifiers. Any recommendations? Radio shack carries a plastic one. Do I mount those under the seat? Could the switch be on a toggle on the headlamp bucket?

I am going to try this and will post pictures when I am done.

Regards,
WIll

DewCatTea-Bob
Posts: 2897
Joined: Sun Nov 01, 2009 10:53 am
Location: Near SE side of Lake Michigan

Re: 250 N/C Wiring

Postby DewCatTea-Bob » Wed Nov 03, 2010 7:11 pm

" ---Do I leave the end ungrounded? "

____ Whichever, all alt.winding lead-ends are to be kept ungrounded !


" Do I run the red/green wire back up through the slots in the stator? "

____ It's find to run your new/4th wire-lead through all the same slots as the three stock wire-leads are routed.


" Will heat-shrink work to protect the wires through the engine case? "

____ That ought to be okay but probably not just on it's own... I've used the rubbery type of fuel-line to use as a new conduit for the alt.cable (of wire-leads).


" ---So I need to get two bridge block rectifiers. "

____ The full-wave diode-bridge for the lighting alt.coil should have at least a 6-amp rating, and the battery charging circuit's diode-bridge should be at least 4-amp, and both ought to have greater than a 50PIV rating.
__ But those bridge-rectifier units which you may find, (while quite cheap), may be difficult to mount & wire-up.
So I'd recommend buying a pair of bridge-blocks with 25-amp & 200PIV, as that is such a commonly produced diode-bridge size, that it's quite cheap for it's specs and also easy to mount & wire-up !


" Do I mount those under the seat? "

____ Yes, that's the most preferred location.


" Could the switch be on a toggle on the headlamp bucket? "

____ Yes, that's what I had always done for myself.
Also, there are different types of 'toggle-switches', so you may wish to consider one that's not just a simple On/Off-switch.


" I am going to try this and will post pictures when I am done. "

____ Do you mean the alt.stator '4th wire-lead' cable-modification ?
That would be nice of you !

____ I've added (directly below), a connection-scheme diagram for the intended twin charging-system, for a 12-volt battery.
If any added details are desired, then please ask.


Hopeful-Cheers,
DCT-Bob
You do not have the required permissions to view the files attached to this post.
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob


Return to “Ducati Singles Main Discussions (& How to Join)”

Who is online

Users browsing this forum: No registered users and 45 guests