Ducati Owners Club Of Canada

Needing Some Electrical Adivce!

The docc defines "vintage" as all Ducatis' up to and including all models of the 750 F1.
6 posts • Page 1 of 1

Needing Some Electrical Adivce!

Postby ratboy1956 » Thu Jan 05, 2012 1:14 am

Hi DOCC'ers! Hope everybody had a good holiday and is settling into a long winter's wrenching in the garage! Hopefully a heated one...

Firstly, forgive my complete lack of knowledge on this subject and my lengthy post! I've tried to do a fair bit of preliminary sleuthing on the web to see what might be an options for the following cunundrum: How to go about getting better lighting, better reliability and better efficiency.

I've come to a crossroads on the electrical integrity of my 1966 Monza. I'm trying to decide between upgrading the entire system to an aftermarket setup with increased watts or modifying to 12v or if I can just leave it stock 6v and live with it. Either way, however it will need some new harness and a good going over since it the insulation is a bit "crispy" in places.

This model has the 60 watt 6v alternator flywheel set up and the big regulator/rectifier.

After reading posts here on the forum and the many on the motoscrubs forum I am a little confused as to what is the best option for my specific wants/needs. My primary concern is to have reliability and better lighting to make me a bit more visible to those bad drivers out there. I plan to ride this bike as frequently and don't want to be stuck with no juice! Key words, Safety, Reliability and Efficiency.

End Goal:
*addition of turn signal lamps (LED type) This should reduce what I have researched as a 3watt draw too about a watt.
*rear brake light and rear running light of LED type ( Also ad a switch to trigger the brake light when the *front brake is applied) These should be of know real drain on the system as they are only on for a very short time.
*improved headlight performance. I would like to run with my headlamp lit all the time, not just at night.

Modern lighting?
I have looked into LED DOT approved headlight units all 12v. The light emitted would be an improvement... the cost is reallly high!!!! Trucklite 7" units are about $250 and draw 2.5 amps at low beam and 4.5amps on high... at 12.8 v say this would be 32/58 watts. A even more expensive unit from JW speaker 5.75" draws only 2 amps for both hi and low consuming 24.6 watts at 12.8v. I'd love to have that light but from what I can tell it is now a Harley Davidson part or something for like $500!!!!! Too bad although I'm sure the price will come down... but I bet they will always look futuristic and out of place on most classics.

I've looked at HID projector lights which I could modify into a vintage style bucket, but I think that would be a experiment at best, and i'm positive illegal. Most 35 watt units are bright, but where they are bright is the question that remains unknown. At start up the ballasts draw more amps and then settle down when at operating temperature... 35 watts seem to be start up around 6amps(76.8watts a@12.8v) and settle down at 3amps(38.4 watts) I've just begun to research this technology but it seems you'd really have to take anything you read on retrofits with a grain of salt.
A video of a retrofit on youtube: http://www.youtube.com/watch?v=dhqevy6G57Q

So perhaps a 35/35 halogen or greater is the best? I'm not sure!

Or maybe add a bunch of LEDs in the headlight shroud for running lights and have them on a on off toggle switch for the day use? hmmm... these you can find in 6v I believe.

Is the logical route to get a stator kit from ELECTREX which converts to 12V and considerably up the available wattage? This could allow provisions for electronic ign etc HAS ANYBODY USED ONE OF THESE?

This would likely open up alot of options for lighting and ign in general but at considerable cost... is it worth it?

If anyone has arguments for staying stock or just modifying the stator and regulator.rectifier for 12V as described by RocketRick in this other Monza electrical post from a few years back;

"To convert an alternator single to 12v, do the folowing:
Disconnect & insulate the 2 ground wires on the stator coil. These are the wires soldered to the backing plate. Heat shrink tubing is good for the insulation. Connect the alternator wires to a 25amp 50 PIV full wave bridge rectifier (availiable at an electronics store- cheap). Connect the positive & negative terminals of the rectifier directly to the battery & ground (+ to+; - to gr; - on battery to gr). The rest of the wiring stays the same. You do not need a regulator. Works great."

I'm all ears for ideas suggestions and warnings! Thanks and sorry for the long, long, disorganized ramble!
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Re: Needing Some Electrical Advice!

Postby The Goochman » Thu Jan 05, 2012 12:51 pm

Check with Road and Race in Australia for alternator upgrade options as well. Phil has been in the business for years.

I will be following this thread as well since I have a couple of widecases that I want to eventually build up as street bikes.

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Re: Needing Some Electrical Adivce!

Postby Mark Lussier » Fri Jan 06, 2012 11:40 pm

You need 12v. Everythng past that is cheap, if you just need it running and reliable. I've run my Commando on Ford Pinto coils and a Kawi Z1 rectifier/regulator combo that came outta a scrap heep. Nothing is special here and almost anything will work. Alternator produces AC, rectifer converts to DC, regulator keeps it under 13.5v so you do'n't fry the battery and everything else.

If you have a generator, you'll be getting 6v DC and it'll need to be replaced .
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Re: Needing Some Electrical Adivce!

Postby Bern » Sat Jan 14, 2012 9:23 pm

Hi Clay,

I'm currently retrofitting my stator/rotor and regulator rectifier on my 74 roundcase. It sounds like the old stator is a center tapped stator Eg. if the current stator has 14 coils the center tap stator is able to provide two ac waves using 7 coils each but the waves are 180 degrees out of phase of each other. This allowed the rectifier to use 2 diodes instead of 4(diodes were expensive back then). If the Monza stator has three wires coming out of it two should be the same color and the other would be the center tap. The two 'ground wires' are the center tap.
This is why removing the two 'ground wires' and using the two alternator wires effectively doubles the AC output voltage of the alternator since you would be using all 14 in series. (this will not work with your current rectifier). If using a modern 12v bridge rectfier you will ignore the center tap wire.

My advice would be to always uses a regulator, it's used to keep that voltage consistent so you don't fry your battery or other electrical stuff you may be using.

In my situation I rewired my stator so it is now a two wire non center tapped (two sets of 7 coils in parallel), I upgraded the rotor to one with much stronger magnets and I put in a modern single phase regulator rectifier. I haven't put the bike back together yet so I can't speak to how well it works but I'm pretty sure it should be OK.

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Re: Needing Some Electrical Adivce!

Postby Bern » Wed Jan 18, 2012 10:49 am

I would also think about putting a ballast resistor in place to protect your coil. Feeding twelve volts through it will roughly double the current and you could fry your coils. That or use a new 12v coil.
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Re: Needing Some Electrical Adivce!

Postby #99 » Tue Jan 24, 2012 2:34 pm

I have RocketRicks 12V snip mod on my 350 N/C except I splurged for a Podtronics regulator/rectifier for a whopping $45.00. Seems to work OK with a 35W headlight and LED taillight. I might switch to a 25W HL bulb as I don't ride much at night, just home from Welland Speedway occasionally in the summer. In the day I sometimes run the 10W "parking" festoon bulb and make sure all the chrome is polished :roll:

I had a 6V PVL coil with a ballast resistor setup but after I went through 3 batteries in 2009 I finally traced the problem to an intermitent short in the coil. I swapped it for a 12V tractor coil from TSC with no ballast resistor and have had no problems, although I have put on less than 500 miles since I installed it.

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