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Discussion Starter #1
I've read through the threads, watched the vids, etc. Am i comprehending correctly that the outer magneto cover is the very first step without draining the oil? Saw several mentions of people saying they decided to "also" change the oil, or do so after the mod, . . .

Just want to keep the surprises to a minimum since i don't own the parking lot where i'll be doing the work. :)
 

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1986 VN750
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You need to drain the oil first, or lay the bike on the opposite site (not suggested).

Another reason for the oil change is to get rid of any metal burs left potentially in your engine after the mod.
 

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Good luck with the mod, RoadHopper. You're a brave man to undertake that without a garage! I'd offer you some working space, but it's a bit of a ride...
 

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No kidding - that's a mod I wouldn't touch in a parking lot. How are you going to grind down the cover?
 

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Discussion Starter #5
Good luck with the mod, RoadHopper. You're a brave man to undertake that without a garage! I'd offer you some working space, but it's a bit of a ride...
LOL ( Shields up ) Bravery is a mixture of 1% idea, 4% stupidity, 5% courage, 50% desperation, 20% frustration, and 20% pure will. ( Shields down ).

( notice how i left any mention of tools out of that equation? ) ;)
 

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FREEBIRDS MC CENTRAL NY
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I'm a tool
 

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Discussion Starter #8
You need to drain the oil first,. . .
So opening that outside cover is going to be greeted by a gush of crankcase oil that would pretty much do the same thing, correct? Or would there only be a dribble from the bottom?

The reason it's still a question is because i was reading other threads talking about adding a port to the top of that area and "T"-ing the oil line overhead to spray oil into the compartment to cool the stator; and because of how low the oil is in the oil-gauge window compared to the height of the rest of the bike. It leaves the impression that the area is "oily" but an air cavity for the most part.



No kidding - that's a mod I wouldn't touch in a parking lot. How are you going to grind down the cover?

Right now this is the planning and design phase. There are various limitations interacting here ( and i mean "here" literally ). In the following time/budget considerations, "ETC" stands for "estimated time of completion". "RSQ" stands for "Roadhopper Stupidity Quotient".

To have the engine dropped in a shop is going to be a minimum of 4 hour labor. Price tag ~$450 with an electrosport stator included. ETC 4 months. No Tux mod. :/

To replace the stator without transferring the mounting of the stator from "inside" the crankcase to "outside" has a 99% RSQ since the odds of getting a stator that not only works the first time, but also lasts another couple of years are out of fiscal tolerance due to my tight budget and Murphy's Law. :)

So, "Tux" mod or perhaps a better name for this might be simply "Stator Mount Transfer Mod" ( SMTM ). Not to discredit TuxedoSeven in any way, but i might not use this extra mounting plate that he more or less designed as integral to the Tux-mod procedure.

That pretty much rules out using a "shop".

A dremel and accessories is about $100. It is absolutely necessary for any sort of SMTM.

The extra plate costs $65 to have it fabricated by an expert ( which is a very reasonable price ). The plate adds width, though to the full assembly so requires a gasket made which is cheap and easy but necessary?

Two alternatives to that route would be either filing down the mounts of the 3 outer-circumference holes the same width as the plate ( which is a bad idea since they probably only have that much width to begin with and/or weakens the mount ) -OR- Skipping the Tuxedo-Plate and using the cover itself since it already has 3 of those holes perfectly bored.

In any case, cutting the inside-stator mounting plate means lots of aluminum filings. Dremel has a circular-guide arm that fits the tool and aluminum is soft and nasty for high speed. I was thinking of making a jig to hold the Dremel guide to the plate at center, then making several scraping passes in a nice dremel-perfect circle sparing only the top two ribs to hold the plate in position until it was scrape-cut out for the most part, then filing the ribs as the final step before pulling the stator out.


Dremel's circular-guide arm:
https://www.dremel.com/en-us/Attachments/Pages/ProductDetail.aspx?pid=678-01

Electrosport Stator:
Buy New Stator Kawasaki VN700 / VN750 Vulcan VN750 Vulcan (86-95)


The final consideration that makes any type of SMTM "necessary" is that i plan on rewinding the old stator myself even if i replace it with the electrosport. I want to experiment with a larger diameter wire and perhaps fewer turns to lower the RPM rate where the coil charges optimally. In effect, a "city-stator" that is intended to deliver a healthy charge when the fan is on idling at a stop light. When it comes time to do a cross-country trip to Washington DC next Fall, i can swap it out for a "highway-stator".

That trip, btw, limits the ETC and budget as well. If i did my math right, when i arrive, i'll need to do an oil change, ( grins ).
 

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Discussion Starter #11
I'd estimate four to five recharges to get a cordless Dremel to finish that job.

Not sure a 'city' stator is really necessary, it should still charge enough to stay alive.

Should only be a small amount of oil when you take the cover off.

I'm not convinced adding oil spray to the stator is that much of a benefit. Then there's windage of the oil on the rotor to think about, as well as aeration. There's a considerable amount of oil coming off the rotor if the oil cap is removed while running.
Yeah, that's the picture i was getting after reading/watching in-depth on this. I 100% agree on leaving the oil alone. Just my totally ignorant opinion, but oil would do more to eat the stator insulation than it would help keeping the heat from doing the same.

About a "city stator": Increased diameter of magnet wire would lower the resistance "a tiny fraction", but certainly help keep the coils cooler. With fatter wires, will end up with fewer coils anyway if the size of each coil stays the same. Fewer coils, and to be specific, counting as few as 18 means only one less coil per arm, would move the RPM range lower for the optimal power transference of the entire magneto. Before i could do any real math on this, i need to have the existing stock stator in hand, count what they used, etc. Design is design is design, etc.. and it will only get "close" to reality anyways.

The most frequent failure of the OEM stator is grounding, which means the heat has taken its toll on the magnet wire's insulation enough that the most "protected" ( from oil ) central windings have begun to lose their insulation ( the stator is shot ). Like i said above, i need to take a look at the OEM stator in its "shot" condition, but, it is likely that because it *IS* OEM that insufficient care was used to protect those inner most windings from their poles.

A couple of things i was thinking about doing besides protecting those poles "better" before winding was applying the electrical insulation during the wind rather than afterwards so that an even coat of "varnish" is applied to every single winding instead of hoping it saturates the bundled coil afterward. The other and probably most important thing to consider is the "varnish" itself. It needs to have three qualities ( or the optimal/reasonable intersection of all three ): High heat transfer to dissipate the heat, low cost, and seriously? only a low to medium di-electric/resistance strength. This is low voltage... 120 or less and high inductance. That's why magnet wire casing is so thin in the first place. The industry is geared more toward RF when it comes to "varnishes". We are concerned more about crankcase heat adding to the heat generated by the coil in a "wet" environment. That's what eats the "original" insulation off those windings. The voltage is too low to have arcs jumping across the windings given they have "anything" non-conductive at all between them.
 

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Someone here did their own rewind in the past year or so. Not sure it was a success, but I'd have to read the thread again.

On coating varnish between wraps: As long as the varnish never moves. If it shifts after drying, the coils are going to be loose. Or at least, looser. The next wrap over a dry coat might break it loose, wrapping over a wet coat.... ugh.
 

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on that rewind, I remember it.. it failed in the end as well, but it did work for a while if I recall correctly.

also, I think it took more than 1 try to get it, as the insulation on the windings was breaking while winding..
 

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Discussion Starter #14
On coating varnish between wraps: As long as the varnish never moves. If it shifts after drying, the coils are going to be loose. Or at least, looser. The next wrap over a dry coat might break it loose, wrapping over a wet coat.... ugh.
rgr that. More like wrapping with wet wire though in this case. In essence, the "factory" magnet wire insulation is simply the wrong stuff in the first place.

I am considering setting up a permanent "jig" for this. A tensioner for wire coming off the spindle, a pan/whatever to dip the wire with new epoxy, a length to allow that to drip/dry a little, and finally a spindle to turn the stator core with a ratchet effect. If the epoxy ( varnish ) is selected carefully, it would make more sense to by bare solid copper wire and forget about the factory stuff. Besides keeping the hands cleaner, the spindle keeps the wire from twisting along its natural axle ( which happens if one wraps by hand turning the wire instead of the core ).

on that rewind, I remember it.. it failed in the end as well, but it did work for a while if I recall correctly.

also, I think it took more than 1 try to get it, as the insulation on the windings was breaking while winding..
..right... which is why with the cost of removing the engine, it makes absolutely no sense whatsoever to skip the "tux cut" part regardless of how it's cut or re-mounted.
 

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Discussion Starter #15
on that rewind, I remember it.. it failed in the end as well, but it did work for a while if I recall correctly.

also, I think it took more than 1 try to get it, as the insulation on the windings was breaking while winding..
And then on the other hand... A super cheap "let's see what happens" approach would be to simply see what sort of characteristics a stator would have using something like this:

JT&T Products 124C 12 AWG Purple Primary Wire, 100' Spool - Walmart.com

What's the worst-case temperature to be expected in a bike that is still operational inside the crankcase? A good design rule of thumb would be to double that temperature and set it as the minimum for our spec.

124ºC = 255ºF Would that do the trick as far as temperature is concerned?
 

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Discussion Starter #17

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I wish I had a spare bad stator to give you, so you could get it rewound by TPE. I gave him my spare last time I did a rewind for a discount.
 

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I may have one. Pretty sure I bought am extra to send instead of my original.
 

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Discussion Starter #20
I may have one. Pretty sure I bought am extra to send instead of my original.
Does it have the wire on it? Two BIG questions easy to solve:

A. Gauge of OEM stator magnet wire.

B. Windings ( turns ) on a single pole. Any pole will do. And is it two layers deep or four?

Electrically speaking since this is a magneto, the number of windings per pole is the central design point. Mechanically speaking, the wire needs to be thick enough to carry the current, but in doing so, *might* limit the number of windings due to physical spacial constraints.

From what i've read here and elsewhere over the past months, this stator could be improved both electrically and obviously thermally. Kaw did *NOT* design this bike with high-reliability in the electronics... anyone disagree?

PTFE ( Teflon ) is the solution i am leaning towards here. Would it make sense that a thicker gauge might take as much physical space with the same windings since the insulating material is thinner yet atomically resistant to oil with a 420F degree operating temperature? Something tells me that Kaw's engineers and suppliers "did not care" about that compared to the bottom line some thirty years ago when teflon was still breaking into the commercial industry.


I'll save us all the shipping costs real easy: After i get a dremel, this stator over here? It's coming out. That's a fact. ;)
 
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