175 electrical questions

[bodge]

i believe from reading various threads ive got an A type engine and frame.can anyone identify my alternator so i can start looking for a cheap regulator rectifier solution ? (the second incomplete bike i bought has a regulator rectifier but i think its the later type)

what spec wire should i purchase to build a rudimentary loom ? the existing wires i have coming off the stator appear to be 1mm multi strand core and 3mm o.d sleeve but i can only find either 1mm (16 AMP) wire with 2mm o.d or 1.5mm (21 AMP) wire with 3mm o.d, both copper core.

ide like to keep the wiring and wires of the stator std when i replace them so im assuming 1 is yellow 2 is white 3 is red ?

IMAG0064.jpg

ignition coil assembly is on the left (smaller gauge wires?)
one end of coil wire soldered to wire 1, other end of coil wire grounded next to it.

power/lighting coil on right(?)
wire 2 is soldered to link in middle which then joins two wires coming off coil assembly underneath.
wire 3 joins single wire on right,i assume this coil is the one that is grounded opposite end of same coil assembly

[DewCatTea-Bob]

[quote= bodge ...
" i believe from reading various threads ive got an A type engine "

____ Of-course an Italian-made 175 would have-to be an 'A-type' motor,, but when it comes to the later/Spanish-made versions, I-myself can't be sure of any such aspects remaining the very-same as the original pre-1961 Italian-versions !



" can anyone identify my alternator so i can start looking for a cheap regulator rectifier solution ? "

____ I believe all the earliest Italian-made 175s employed alternators produced by 'CEV', but yet the stator-unit you've posted appears to be a later DUCATI-version.



" what spec wire should i purchase to build a rudimentary loom ? the existing wires i have coming off the stator appear to be 1mm multi strand core and 3mm o.d sleeve but i can only find either 1mm (16 AMP) wire with 2mm o.d or 1.5mm (21 AMP) wire with 3mm o.d, both copper core. "

____ I'd acquire some of each, but the thinner wire should be adequate enough in any case.
Just be sure that your final-choice is at-least '18-gauge' (but not thicker than 16-gauge).



" ide like to keep the wiring and wires of the stator std when i replace them "

____ That's usually always admirable and of-course pretty-sensible ! _ However it may likely limit future adaptation endeavors for various charging-system schemes which may later become preferred. _ So you may prefer to consider replacing the original set of three wire-leads rather with two pairs.



" so im assuming 1 is yellow 2 is white 3 is red ? "

____ Have you numbered each of them according to the order they're connected to the stator terminal-board, or what ?
I'm not convinced that the yellow and white wires are in correct order,, so to help be sure of which is which, please try scraping-off the outer color-contamination so that the original-colors are more purely detectable.
__ I've altered your picture in hopes of getting everything more cleared-up.



" ignition coil assembly is on the left (smaller gauge wires?) "

____ The stator 'power-coil' meant for powering the ignition-coil always has the thinner gauged coil-wire, and is supposed to attached to the yellow-wire (that connects to the ign.coil).



" one end of coil wire soldered to wire 1, other end of coil wire grounded next to it. "

____ If you're meaning to indicate that the ign.power-coil is connected to the yellow-wire and stator-ground, then that indicates that your stator-model is probably the 28w.version (and not the 40w.version).



" power/lighting coil on right(?) "

____ The stator lighting-coil is always connected to the red-wire (for the main-lights), regardless of being either a '28-watt' or '40-watt' stator-model.



" wire 2 is soldered to link in middle which then joins two wires coming off coil assembly underneath. "

____ That the white-wire is rather associated with the 'lighting-coil' (instead of the 'ign.power-coil'), confirms that your stator-model is the 28w.version.



" wire 3 joins single wire on right,i assume this coil is the one that is grounded opposite end of same coil assembly "

____ The opposite-end of the coil-winding connected to the red-wire is indeed grounded directly to that coil-core (on the stator-plate).
The white/center-wire is a center-tap that bleeds-off some of the lighting-coil's power for charging the battery.
__ Here follows a link to a much related thread that you ought-to be interested in reading-through. ... viewtopic.php?f=3&t=1883&p=14013#p14025


Hopeful-Cheers,
-Bob

[bodge]

thanks for response bob,ide assumed my bike was italian as it has a dm prefix on engine and frame but i dont know if thats definitive.
your right about the build of the stator it is indeed ducati as is the flywheel.
the wires are shown in the order they enter the back plate.
heres a pick of the back plus flywheel

IMAG0066.jpg

[DewCatTea-Bob]

[quote= bodge ...
" ide assumed my bike was italian "

____ I suppose it could actually be probable that the Italian-factory continued-on producing 175-models even-though I believe 175s were no-longer imported into the U.S. after 1960.
Or rather perhaps your 175's original alternator was later replaced with one meant for a 160-model.
__ Are you also inclined to fully adopt the entire stock electrical-system of a 160-MonzaJr as well ?



" the wires are shown in the order they enter the back plate.
heres a pick of the back "

____ Thanks for adding that pic.view,, as it's now certainly obvious that none of them happen to cross-over one-another (where they were out of view, hidden behind the plate-entry), instead of having to assume so.
From just the underside-view, it sure looks like the yellow and white wires are both directed towards the ign.power-coil, (which would indicate a 40-watt alt.model) !
__ Do you have an ohm-meter with which to check the circuits of those two power-coils ?


Hopeful-Cheers,
-Bob

[bodge]

just poped out and picked up a cheap multi meter,theres little or no resistance between each wire and earth or from any wire to any wire.
according to the manual which is a little hard to understand i think that maybe thats o.k .
the paired wires are 2 and 3 white? and red
dont know if the american market got different but the manual states that the only models with the cev were the 125s and 175s

IMAG0069.jpg

[DewCatTea-Bob]

[quote= bodge
" theres little or no resistance between each wire and earth or from any wire to any wire. "

____ That tends to confirm your stator is a 28w.model, (as the white & yellow wires of the 40w.version are isolated from earth/ground).
__ A worthy ohm-meter has to have an extra-sensitive setting that measures resistance-levels under 1.0-ohm ! _ Otherwise it will simply register actual resistance readings as nearly zer0-ohms.



" according to the manual which is a little hard to understand i think that maybe thats o.k . "

____ That may be fairly true for when a mere 'continuity test' is sufficient enough for determining a particular test result. _ However for testing the actual value of a power-coil, far more exact resistance-readouts are then required.
__ I've already provided a link to another thread-post that should inform you what to look for.
After you've measured your sub-ohm resistance-levels,, then let us know what readings you found, and then I'll next evaluate what-all they may likely indicate.



" the paired wires are 2 and 3 white? and red "

____ Please try scraping the coating of the two non-red wires, so as to obtain a cleaner look at the white & yellow jacket-coatings.
__ It does make sense that the white-wire is connected to the same power-coil as the red-wire is connected to, (providing that the alt.stator is a 28w.model [and not the 40w.version]).



" dont know if the american market got different but the manual states that the only models with the cev were the 125s and 175s "

____ I believe that some early 200s also received CEV-alternators.
I never before heard-of a 160-type alternator being found on any 175-model, until now that you've indicated so.
Are you really-sure that your motor's bottom-end is actually that of a "175" ?


Dukaddy-DUKEs,
-Bob

[bodge]

thanks again bob, had a scrape of the wires still not totaly conclusive but probably yellow 1. white 2. red 3.
missed the link earlier had a quick look all seemed a bit out of my depth,i think with the price of a worthy ohmeter ontop of the price of whatever regulator i need to go with this probable 28w stator i may as well reluctantly fork out for a 12v conversion.

not sure of anything now bob the cases are marked with a dm175 engine number and all the castings have 175 part numbers so far.
i bought an even more incomplete 250 off the same vendor which had a knobbly tyre on one of the wheels and a scrambler type front pipe but he said he didnt think it was a genuine scrambler but im now wondering if the stator could have come from that? (edit, unlikely as just checked ,engine number predates change)

in the documents section of this site theres an electrical supplement marked "usa models" as other english language ducati publications seem to be aimed at both u.s and u.k markets or rather dont stipulate i wonder if electrical specs were unique for u.s models.

[DewCatTea-Bob]

[quote= bodge ...
" had a quick look all seemed a bit out of my depth, "

____ The main info to've been found over-there within that past thread, is the ohm-readings that ought-to be expected for the 28w.stator. _ Your questionable lighting-coil ought-to have a reading of .4 ~ .7 ohms.
You should first try your "cheap" meter on the ign.power-coil, cuz it's ohmic-value should be between .8 ~ 1.1 ohms, and your ohm-meter really ought-to be good for reading down to 1-ohm (which is thusly close-enough to trust such value-reading for that coil).


" i think with the price of a worthy ohmeter ontop of the price of whatever regulator i need to go with this probable 28w stator i may as well reluctantly fork out for a 12v conversion. "

____ I'm really not in agreement with such an assessment, since an adequate multimeter should be no higher-priced than 70-bucks -($70. US.) and a suitable rectifier less than 5-bucks,, while aftermarket conversion-kits cost at-least five-times as much !
__ And if you wish,, most of the power (produced by the ign.power-coil) that's normally left unused & wasted by the ign.system, could instead be diverted and rather used to charge a 12v.battery !


" the cases are marked with a dm175 engine number "

____ Then the bottom-end must indeed be that of a 175cc motor !



" all the castings have 175 part numbers so far. "

____ That however doesn't mean too much, as all other motor-sizes also include the same '175' marking on any interchangeable motor-casting/covers which have been left unchanged since that original/175 OHC.motor.



" i bought an even more incomplete 250 off the same vendor
but he said he didnt think it was a genuine scrambler but im now wondering if the stator could have come from that? "

____ Most n-c.scramblers employed the '40-watt' model, but only the 1966-Scrambler came stock with the 160-type 28w.version.
So let me know the motor-number of that 250 parts-bike, and I'll confirm whether it's at-all an actual possibility.



" i wonder if electrical specs were unique for u.s models. "

____ The electrical-systems were always essentially the same, with the stipulated-differences being only having to do with related USA.lighting/('DOT')-requirements.
(Perhaps also some Berliner-inspired body-work variations could possibly be included amongst such 'USA-only' type listings as well.)


Duke-Cheers,
-Bob

[bodge]

thanks again bob ,fraid my cheap meter just slowly goes down to a reading of 0 on anything i put it on.
250 is dm250 85xxx 175 is dm175 07xxx
my comment on getting the 12v conversion was based on the fact over here ide be paying £65 just for a model specific regulator rectifier unit and ive got no idea what a quality ohmeter would cost but generally stuff like thats cheaper for you over in the states.
if you can point me at a $5 rectifier i would be most grateful

[DewCatTea-Bob]

[quote= bodge ...
" fraid my cheap meter just slowly goes down to a reading of 0 on anything i put it on. "

____ Seems to be a good candidate for return & exchange towards a good-one that's at-least adequately suitable ! _ (And then after you've tested the 'replacement', you could then pretty-much do-same once-again as well.)



" 250 is dm250 85xxx "

____ That 250 motor-number is a couple years too old to have come stock with a 28w.stator-model !



" 175 is dm175 07xxx "

____ I'm not at-all sure about 175 motor-numbers, but I would've expected the older/(pre-1961) 175-models to exhibit motor-numbers similar to the oldest 200-models,, so quite perhaps yours is a later 175 production model.
Hopefully someone outside of the US.market can conform whether Italian 175-models were still kept available up-to the later year when the 160-model first became available.



" my comment on getting the 12v conversion was based on the fact over here ide be paying £65 just for a model specific regulator rectifier unit "

____ The Ducati 4-pole alternator really doesn't produce enough power to require a regulator, so long as the battery is-not a dinky little thing !
In-fact Ducati's 28w.system merely required just a simple power-diode (to keep the battery charged) !



" ive got no idea what a quality ohmeter would cost "

____ I'd expect that no more than 25-pounds would get you a suitably decent unit.



" if you can point me at a $5 rectifier "

____ Here's a link: viewtopic.php?f=3&t=1781&&start=10#p13533 to a related thread that includes associated discussion of a suitable rectifier 'block' (of power-diodes arranged in a 'bridge' circuit).
The likes-of the pictured "bridge-block" included within my referred thread-post, ought-to be available at most-any local electronics-store for 1 to 2 British-pounds !
Here follows an eBay link to a similar bridge-block with way-MORE than acceptable operating-specs for possible application with whatever your project-system may eventually become... http://www.ebay.com/itm/1pcs-High-Curre ... 3a8d98eb4c


Hopeful-Cheers,
-Bob