Methods to Increase Power from N-C twin-wirelead Alternators

[bettyann]

Dew Cat Tee Bob
I went to Gainsville, FL this Fri, and picked a small pick-up truck full of barn find misc.Ducati motors and forks ect.
One of the motors is a 200cc duke single. Upon inspecting the flywheel it was odd to me,looks the same as a brass mk3 or scr,
but is made out of aluminum, with what looks like 2 faded yellow wires. I've never seen one like this before. My first Duke was a 1962 200ts,looked just like a 4speed Monza. Were these flywheels of any use to to my later 250 4speed restorations?
Might rev faster? Also picked up in the barn find,250 5 speed complete motor ,250 4speed,(2) 125 bronco,125 moto guzzi,
3 250-350 complete heads,tach drive,Nice set of Cherani, forks for wide case, wide case frame,2 wide case scr tanks.
All this stuff has been sitting for many years,some motors are movable some stuck. But to clean up and take apart,for future projects or spare parts. Capt Paul

[DewCatTea-Bob]

" I went to Gainsville, FL this Fri, and picked a small pick-up truck full of barn find misc.Ducati motors and forks ect. "

____ I used to live just to find & acquire such finds ! _ Hope you experienced that great-feeling like I used to get when-ever I came-across such a batch of treasure.


" One of the motorUpon inspecting the flywheel it was odd to me,looks the same as a brass mk3 or scr,but is made out of aluminum, with what looks like 2 faded yellow wires. "

____ While I do have a fair-amount of experience with the 200-motors, all of the 200-models were already imported (& probably sold) before I became involved into motorcycling myself,, so I was never real familiar with all the various 200-models which were once produced.
__ It's my understanding that Ducati first used alternators made by CEV for their 175s and their early 200s, before beginning to produce their own alternators for their later model 200s.
I haven't messed with any 200-models since the early '70s, so my memory is no longer real clear as to what all I did once learn about 200 electrical-systems.
I do recall seeing aluminum flywheel-rotors on at least some of the 200-motors but, I don't recall which model-names did or didn't have those, as opposed to brass-rotors. _ I only recall having concluded that the models with wilder cams must also employ the lighter rotors.
Since your 200-alt has just two wires, it's then likely not one of the older CEV models.


" Were these flywheels of any use to to my later 250 4speed restorations? "

____ As far as I know, they are all interchangeable, and so yes, you should be able to make use of such for either motor-size (regardless of 4 or 5 speed). _ But how about showing a picture? - Just to make sure of exactly what rotor you have.


" Might rev faster? "

____ Yes, the lighter rotor should less impede crankshaft-acceleration but, it's nothing much noticeable much above 3000-RPM.


Treasure-Cheers,
-Bob

[jbcollier]

No mention of actual outputs so far.

Here is my conversion:

http://s250.photobucket.com/albums/gg26 ... CN1250.jpg

Added two extra coils, not for more windings, but to allow the use of thicker wire. Still single phase, two wire, regulated by a 12v Boyer.

It powers a Rita twin plug system with a green Dyna coil and ballast resistor (4 ohms total) and a 35w headlight. It charges the battery at idle with the headlight off. With the headlight on, it starts charging the battery at 2500 rpm. I always run with the headlight on and never have to charge the battery.

[wcorey]

Here is my conversion:

http://s250.photobucket.com/albums/gg26 ... CN1250.jpg

Nice neat job on that, I like how you glassed over the coils.

I've been playing around with alternator update schemes and had thought of doing this at one point but ran into issues that steered me toward other choices. One problem was that the two additional coils block the access cutaways in the formally unused positions on the core for the two top mounting screws on the backing plate. To get around this I figured I'd need to separate the stator from the backing plate then make a new backing plate with threaded mounting holes in place of the rivets for the stator/core. The plate would be mounted first and the stator would then go on after. (I'd actually have to make a new plate in any case because it's going into a widecase motor.)

I'm curious as to how you dealt with the two top mounting screws for the backing plate? Can you squeeze a couple of hex bolts in at an angle first then alternately wrench them in?

[jbcollier]

You mount and wire in the two extra coils after you mount the stator plate.

[DewCatTea-Bob]

By: wcorey...
(I'd actually have to make a new plate in any case because it's going into a widecase motor.)

____ I've been down the same road you're considering.
I'm curious about a couple things though...
First, how is it that you find yourself wishing to install a n-c stator on a w-c motor-case ? _ And, why do you feel any need to add extra coil-windings onto the two originally bare poles ? - (Is it cuz you wish to run more powerful lighting,, or does your own particular battery/load-system not positively balance-out, for your particular circumstances of night/city-riding ?)


Dukaddy-DUKEs,
-Bob

[wcorey]

You mount and wire in the two extra coils after you mount the stator plate.

Ah, I guess that works too...

First, how is it that you find yourself wishing to install a n-c stator on a w-c motor-case ? _ And, why do you feel any need to add extra coil-windings onto the two originally bare poles

My motor (450 R/T) came with the 'magneto' type battery-less setup with the two coil stator and heavy 4 pole brass flywheel. I found a deal on an aluminum 6 pole flywheel with an n-c stator and figured on mounting it up to a w-c adapter plate then going with a 12v reg/rec. I rigged up a test fixture with a 3450 rpm motor and was a bit disappointed with the output. So yeah, more low rpm power for better lighting is my goal. I also tend to like the 'snap' of lighter flywheels so that also came into play.

One thing led to another as it always does and I found that I had a 3 phase alternator from an early 80's suzuki with a 93mm stator, which just happens to fit in the 6 pole ducati rotor. It has 18 coils and i thought, hmmm 18 coil 3 phase probably means 6 sets of three coils, I wonder... Talked to someone at Electrex and they thought it may work and were actually pretty interested in the results. I made an adapter plate and tried it, didn't work, oh well.
But then I thought, what if I can machine the suzuki rotor <edit> to fit the ducati crank? The outward facing rotor mounting used on most 'modern bikes' makes the hole on most of them too big to just machine in a new reversed taper so I put in a bigger diameter reverse taper and made an adapter spacer/taper piece to take up the difference and it fits right on. The weight is about right, maybe a few ounces heavier than the stock aluminum one. Problem is that it's just a bit deep and to squeeze it in the stator mounting plate starts getting thin.
But now I'm hooked on 'the project', started doing some research and looking on ebay for cheap alternators. If you're not too picky components can be had for 10-20 bucks, shipped. I also have a local car junk yard with a few misc old bikes( yeah, I know, 'bikes' dates me) that they don't care much about and let the parts go for next to nothing.
I now have a single phase setup from an 80's kawasaki working, will run a 60w light while putting 14.8 volts into the battery at 3450 rpm. Still had to machine the rotor but didn't need the taper/spacer part, the stator fit the adapter from the 3 ph setup. I still want to go 3 phase though as it's more efficient and I have a 3 ph rec/reg that has that nice 6th wire to monitor and adjust output according to need rather than shunting it to ground. At present I also have adapted a gsxr 1000 rotor that easily fits but I'm concerned that it's too light. Next I'm picking up a 3 phase kawi rotor as it will work with the old suzuki stator and I'm hoping it's the same thickness as the single phase kawi version that fit's in so well.

Here's the setup from a week ago, the pile has since grown a bit though...

[DewCatTea-Bob]

" My motor (450 R/T) came with the 'magneto' type battery-less setup with the two coil stator and heavy 4 pole brass flywheel. I found a deal on an aluminum 6 pole flywheel with an n-c stator "

____ Oh, I guess I should've expected that particularly likely set of circumstances.
__ The stock R/T-alternator would've been sufficient for conversion to a 6-volt or 12-volt battery-system with a low power-load. _ But I can understand seeking an alternate charging-system with more power, if you wish to use high-powered 12-volt lighting.


" I rigged up a test fixture with a 3450 rpm motor and was a bit disappointed with the output. "

____ So correct me if I've misunderstood,
I gather that you made an adapter-plate which could let you mount the n-c '60-watt' 6-pole alternator to your stock 450R/T-case but, you were not satisfied with that alt.stator's power-output,, that all correct?
If so, how was that alt.stator's wiring connected to your test set-up ? ...
__ To obtain good/usable charging-power figures, you should not rely on a volt-meter, but rather on an ammeter that's connected in series with your battery.
Then with your intended lighting-load connected to the battery, note the amount of amperage charging the battery. _ When there's no current going in or out of the battery, that's referred to as the 'break-even point'.
__ If the n-c 6-pole alternator is wired-up right, I believe it should provide sufficient power for most 12-volt systems.

. . .

" I had a 3 phase alternator from an early 80's suzuki with a 93mm stator, which just happens to fit in the 6 pole ducati rotor. It has 18 coils and i thought, hmmm 18 coil 3 phase probably means 6 sets of three coils,
I made an adapter plate and tried it, didn't work, "

____ Seems like it ought to have worked, but keep in mind that "three coils" are incapable of sharing any N/S-pair of magnets. _ So maybe it's (more likely) actually three sets -(windings) over 6 coils, each !? _ It should be just a mater of how the three separate phased-windings are connected-up.
__ Do you also have the related Suzuki rotor which was originally matched with that 18-coil stator?


" ( yeah, I know, 'bikes' dates me) "

____ Don't think I understand what's meant by that.


____ Anyway, all this experimental research you're doing is quite interesting and very much deserves to be moved to it's very-own thread ! _ (Providing you're still in a sharing-mood about most of it, or hopefully at least the most fruitful of it all.)


Hopeful-Cheers,
-Bob

[wcorey]

I guess I should start a separate thread for this, it's (the project) getting pretty involved. If you want to move this and the other post to it's own thread that's fine by me...

____ So correct me if I've misunderstood,
I gather that you made an adapter-plate which could let you mount the n-c '60-watt' 6-pole alternator to your stock 450R/T-case but, you were not satisfied with that alt.stator's power-output,, that all correct?

Almost correct. My 450 motor is in about as many pieces as it can be in and won't be able to run any alternators for a while. By "test fixture with a 3450 rpm motor" I meant a bench setup with the rotor attached directly to an electric motor, you can see it on the bottom left of the first picture. I never bothered to make an adapter plate for the n-c stator, I adapted it to the test fixture. To test output I simply ran the two stator wires through a 12v full wave reg/rec with a 60w h4 light on it and a slightly undercharged battery. The light was obviously not even near full brightness even after disconnecting the battery so I didn't even bother to measure voltage or current. Was just "ok, next option is...".

__ Do you also have the related Suzuki rotor which was originally matched with that 18-coil stator?

That's in the part of my previous post where I screwed up and typed stator instead of rotor, I can see where that would be confusing. I fixed it...

"But then I thought, what if I can machine the suzuki stator (should have read rotor) to fit the ducati crank? The outward facing rotor mounting used on most 'modern bikes' makes the hole on most of them too big to just machine in a new reversed taper so I put in a bigger diameter reverse taper and made an adapter spacer/taper piece to take up the difference and it fits right on. The weight is about right, maybe a few ounces heavier than the stock aluminum one. Problem is that it's just a bit deep and to squeeze it in the stator mounting plate starts getting thin."

The second picture is that rotor, it's depth/thickness is pushing the dimension of will fit between the primary drive gear and the stator mounting plate, so that the plate can only be about .060" thick below the screw heads affixing it. if I made it from steel that would likely be ok but I feel it's marginal using aluminum. I believe it would be fine on an n-c motor because the mounting plate is smaller in diameter.
Anyway, by that time I'm having fun with all this and have already scoped out a bunch of cheap ebay items that would surely work better, I decided to go for as many solutions as possible without spending over $100. As a bonus, when I'm done I'll be able to try 4-5 different flywheels weighing from ~1.5 to ~4 lb's.
I come from an R&D background and it's more or less what I did for 20 years when I had 'real' jobs so it's hard not to get caught up in these things sometimes, force of habit.

" ( yeah, I know, 'bikes' dates me) "

____ Don't think I understand what's meant by that.

(Off topic warning )
That was a 'disclaimer' specifically for you! You have commented in past posts that people who refer to motorcycles (or, God forbid, DUKEs) as "bikes" ( I'm guilty) are likely "new-boys" or Harley types and don't have the same level of... respect or maybe reverence, I guess..., for the machines as the people who were riding them when they were new. Just a generation gap kind of thing, I think. I've also noticed that you refer to Japanese stuff as "Jap bikes" with probably no disrespect intended, it's just an easy abbreviation (I use it also). But at some point in time that terminology started being taken to covey disrespect/disdain and is considered by some (of the still newer 'new-boys') as mildly derogatory. Again, just the perception of those in a particular generation. UJM (Universal Japanese motorcycle/machine) seems to be the common currently used PC abbreviated term...

[DewCatTea-Bob]

" Almost correct. "

____ I had understood okay that your testing was done on on your test-rig (not the R/T), so I was only wrong that you may had already figured-out & finished a way to mount the n-c stator to the 450-case.
(Guess I shouldn't have mentioned both thoughts within the same sentence.)


" To test output I simply ran the two stator wires through a 12v full wave reg/rec with a 60w h4 light on it and a slightly undercharged battery. "

____ This leaves concerns to be addressed... Please correct me if I'm wrong.
I'm gathering that you connected the n-c stator's two wire-leads directly to a full-wave rectifier-unit (with incorporated unknown regulator-type), thus of course ignoring the normal ground-connection at the stator, correct?
It's too bad that you didn't take either a voltage or current reading from that 60-watt light, so that we could have then figured the wattage being produced at that RPM.
That it was not fully brightened, only tells us that the light was drawing under 5-amps. _ Which is of course expectable under 4000RPM.
__ Also, not knowing the manor of the regulator used, it may taint results. _ So, as long as your testing is kept under an hour, you need not employ any regulator for these tests of yours, (unless it's the regulator itself that you're testing) !
I suggest that you use only a plain full-way rectifier (known to be completely good!), so that you can more certainly trust the result-figures.

. . .

" That's in the part of my previous post where I screwed up and typed stator instead of rotor, "

____ Already had (naturally) realized that slight term-error, of course !
__ I only asked about the whereabouts of that Suzuki-rotor, as I much wonder if you could still compare it's magnet-layout with that of the n-c DUCATI-rotor. _ As otherwise, I see no reason why the DUCATI-rotor couldn't work with the 18-coil stator. _ What's the difference between those two rotors, (other than their width-dimensions)? _ Are their inner-diameters much different?
Is the magnet-layout, in someway, much different? - (Which I'd doubt if their related stators have about the same outer-diameter, as you mentioned).
(I'm thinking that this is about the best chance-find which you'll come-across, for a 3-phase alternator that could be fitted to your project.)

. . .

" That was a 'disclaimer' specifically for you! You have commented in past posts that people who refer to motorcycles (or, God forbid, DUKEs) as "bikes" "

____ I was afraid of that! _ As that then means that you haven't correctly understood where I'm coming from on that issue, exactly. ...
I'm actually fine with the term 'bike' when it's used in place of 'motorcycle' (or 'cycle' as we always said until the late '80s). _ My only issues with that term, is it's blatant (seemingly cult-like) overuse, and also, when Duc.single-owner's actually seem to go-out-of-their-way with preferring to refer to their 'DUKE' as a "bike", as if it really is merely just another 'bike' -(which even I myself would possibly think of a Duke, if I were to see one for the very-first time), as far as they're concerned (in their own mind) ! _ Actually, I think that's just fine, so long as that's indeed the actual case with the particular individual, (who likely inherited his duke). _ But for those of us who have the perception to realize what a particular 'gem' our DUKEs actually IS/are, ought to use some kind of term of honor which separates our DUKEs out from the crowd of all the other mere 'bikes' ! _ And the term "Duke" was already provided for that purpose, back when I myself was still calling DUCATIs "cycles".
So if one has really come to care (as I have), then they ought to try to avoid referring to their 'DUKE' as a 'bike'. _ And I'd think that most everyone here would be in that same boat.
__ I recall back in the early/mid '60s when I was switching-over from Schwinn-bikes, and had Harley & Brit-bike riders point to me & my friends on DUCATIs and say things like "Hey you kids, when ya grow-up, get rid of your bikes, and get yourself a REAL cycle!". _ We were of course then to feel quite insulted !
Now these days, the term 'bike' has become applicable for ANY motorcycle,, I think because of the magazine named 'Bike', that came-out in the '80s and covered only 'Custom-Bikes' which were really worthy of a 'stand-out term', so everyone then came to want THEIR motorcycle to be a 'Bike' also, (thus then demeaning the unique-term, by now-days).
Thus I can't see calling any of my DUKEs a 'bike' ! _ So I'm surprised that others (of those like most of us here) can feel okay with doing that.


" I've also noticed that you refer to Japanese stuff as "Jap bikes" with probably no disrespect intended, "

____ That's right.
Of course all bikers who've been around-the-block have learned that those who are strictly loyal to their whatever nonJap-bike brand, most often use the term "Jap-bike" in a nonpositive-light, thus that term can certainly be thought of as derogatory when used within wording which indicates so,, but otherwise, it's to be taken as neutrally as is the term 'Brit-bike'.
Besides that, it's sort-a hard to associate actual 'putting-down' by exemplifying that which is actually somewhat superior. _ (Kind-of the same as trying to 'put-down' some guy, by saying his mate is a Victoria'sSecret-type.)
So a Jap-bike rider may have 'missed-The-boat', (from a nonJap-bike rider's point-of-view), but the boat HE's in is actually less likely to sink.


" UJM
seems to be the common currently used PC abbreviated term... "

___ So that's a neutral-term now? _ Or is it the latest put-down slang?
Until it's better known what that's meant to mean, I'll just stick with that which is more obvious to realize. _ As I really feel the need to be as clear as possible on most everything.


Hopeful-Cheers,
-Bob