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Discussion Starter #1
My top winding is toasty black and i have a dead short to ground on all three stator leads.

Anywhere i can get a good one that isnt custom hand wound in gold? Don't wanna go chinese, don't need hand wound quality. Wheres the middle ground?

(No mosfet regulator, etc. running stock reg relocated).

Pic of upper windings:
 

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Thats 'Mr' Jr Member
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My top winding is toasty black and i have a dead short to ground on all three stator leads.

Anywhere i can get a good one that isnt custom hand wound in gold? Don't wanna go chinese, don't need hand wound quality. Wheres the middle ground?

(No mosfet regulator, etc. running stock reg relocated).

Pic of upper windings:
I got one from Willie's Cycles. Haven't installed it yet but I hope it's a good one.
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Discussion Starter #4
I wish i could allow myself to buy oem used on stators, but these go through so much on the vn's they are always turned up to 11. Anything mechanical, any day I'd buy. Electricity and this bike are like villains fighting daily.
 

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Discussion Starter #5 (Edited)
Well it doesn't get much clearer than this here is a dead short reading on the burnt winding grounded to the case of the engine. Seems kind of weird that it didn't blow the fuses since I have the three fuse mod on the Stator.
 

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Discussion Starter #6 (Edited)
Two things: why didnt it blow the fuses if its dead shorted, doesn't the regulator feed back..... hence the need for the fuses or was there another reason for that mod?

Most importantly...... why cant i just skip the agony of every hose and wire removal to get the engine out and tilt the engine over a little to clear the frame when pulling the stator cover? I'll pull the mounts to free it, but I've built 6 vulcans from a frame and I specifically recall that engine will tilt over when balancing on a jack. Seems like the catch point is the front of the cover on the downtube of the frame. WHY doesnt THAT side of the frame disconnect instead of the other side kawasaki? Uhg ......
 

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Tilted mine for the stator, there's a thread with pics but the pics are probably dead. Will try to revive the pics.

Pics still showing for me: http://www.vn750.com/forum/31-engine-exhaust-cooling/78449-2003-vulcan-750-stator-replacement.html

Key points for me... Ratchet straps to stabilize and hold, floor jack/wood block, and a large wooden mallet that held the correct tilt angle. Mallet between front head and frame tube. Bevel gear, carbs/cables, exhaust manifolds, all left in place. Earshaved at the same time, no airbox. Have to slide the engine to the right, partially away from frame, then tilt. Alternated jack movement, strap adjustments.

Worked well enough to do it twice in two days.

Wille's is rewinding those stators. Majdsaster is our guinea pig. Congrats Maj!

Kawi must've thought clutches would be more problem than stators. How wrong they were.

Edit: Apparently not enough amperage to pop the fuses. Fuses too large? Once the winding shorts, no current flow?
 

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Exactly. Once the windings short to the lamination, no current (or very little) goes thru the fuses. The fuses can protect the stator from a shorted r/r but not a shorted stator
 

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Discussion Starter #9
Ahhh yeah that was it. I knew i did it for a reason. It's got shaved pickups, external relay ignition, blue wire, 2 wire, and every damn thing else and after a while i forget why i did it all.
 

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Discussion Starter #10
So, anyone not convinced the stator is bad? :)
 

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Discussion Starter #13 (Edited)
Ok so this is going to end up an experiment in theory.

First, I've ordered the caltric. Let's get that out of the way. Read on and you'll see why.

Everyone knows cheap parts are crap for various reasons. Everyone knows VN's eat stators. So if someone bought the $140 stator option from ebay (mid range) instead of the $60 option (caltric) then there won't be any problems, right?

Yet over and over we see "I've had three stators die and i bought (tpe, etc)". The bike still ate them and didn't give a damn which one you put in there.

So we move on to why they die. Sure some may be wound with better lamination and dipped in blesssed rubber coating and they'll take a little longer to die than a cheap one. It's just better, it'll last longer. The killing maching however is not the draw of current that does the damage, the cheaper lamination in the insulation, nor the rubber dipping. They get too hot. Thats it. End of story.

So we need to forget about covering up an issue with a big expensive strong custom stator that can take the abuse. If a wife gets beaten every night and wears long sleeves to cover it that isn't a fix to a genuine problem. The problem with the VN is several flaws that cause it to demand too much from the stator. We need to put as much as we can back on the battery and let the stator feed the battery instead of the bike.

Some of these measures we have taken include the ignition mod with the relays, for instance. These are good mods that will help. Anything and everything else that can be done to eliminate load to the stator directly and put the battery in the middle like a capacitor will help reduce load. Speaking of..........

It just so happens i used to own car audio stores and have a LOT of experience with farad caps. They keep high loads and spikes out of the supply line so that power supplies don't suffer from heat issues due to lack of available source voltage. So the first mod to my bike with the cheapie stator....... a farad cap on the battery. This alone will eliminate high heat spikes from demands of the VN.

SO assuming i have done all the common mods to the bike we do, now we get on to eliminating the sources of these spikes. Every single bulb on the VN draws a LOT of wattage. So we can take over 60 watts of demand off the stator just by swapping the rear and front bulb with an led option, much less replacing all of them and saving over 80 watts of constant demand.

Another monster, the cooling fan. There are several brushless options that are more efficient.

Now we have dropped a LOT of load from the stator, put in a farad cap to eliminate any heat from the many constant voltage spikes, and did all the mods we already do to reduce loads on our bikes.

The fact is that if the cheapie stator is built properly and to do nothing more than what it's rated to do....... it won't fail.

Now, the money spent on leds, brushless fans, etc probably levels out with the price of a better stator, but everything on the bike is now much better, the stator isn't going to fail again, and you're driving a bike that doesn't have as many flaws as the guy next to you with the $350 stator thats going to overheat..... one way or the other, eventually.

So let's see...........To be continued
 

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My theory is, take as much as possible away from the Junction Box. Bypass all three JB relays. Shorts in JB, load on the stator.
 

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probably the single worst culprit is the choice of a shunt style regulator. by design, these cause the windings in the stator to constantly providing the maximum amount of current possible (rpm and gauge of the stator wire effects this).

at the very minimum, a mosfet style shunt regulator to help this out. best possible solution, a non-shunt style regulator is probably the ultimate solution.
 

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Ok so this is going to end up an experiment in theory.

They get too hot. Thats it. End of story.
I like the way you think.

As far as reducing stator load, the latest tweak I've tried is the SH775 series regulator/rectifier. So far, so good. MAJOR improvement over the FH020AA it replaced, at least on my bike. BTW, roadstercycle.com was my source for both the FH020AA and SH775. The latter has been superseded by the SH847 due to a radical price increase on the SH775. Also replaced the taillight bulbs with LEDs -- a surprising (to me, anyway) reduction in load. Hadn't considered replacing the front sealed beam with a LED unit, even though I *really* like the one I put on my Royal Enfield. Didn't break the bank buying it, either: about $160 U.S. if I recall.

Any pointers toward a suitable brushless cooling fan replacement? The fan coming on is simply the "two" part of the "one-two" punch delivered to the stator by riding this bike in temperatures above 95 degrees F :-(. Agreed that heat is the stator killer, and since I can't do anything about that large yellow ball in the sky, reducing electrical load and doing whatever's possible to improve engine cooling are about all that's left in the arsenal.
 

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I'm curious what marked improvements you've noticed after going to the SH775 vs the FH020. I will likely do the conversion, as well, but I would love to hear what your first-hand experience is with them
 

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ubertalldude: what I was looking for, and what I honestly believe I got, was a reduction in the amount of heat generated by the stator itself. The series R/R does its thing by switching the stator windings on and off, unlike even the best shunting MOSFET R/Rs that keep the windings running flat-out (maximum output) 100% of the time.

At the time I bought the SH775, there was no price difference between it and the FH020AA, so the decision to go with the series R/R was a no-brainer.

Personal observations? The engine takes longer to warm up regardless of riding season. Somewhere in this forum I related the experience of people who actually did temperature measurements of the engine case cover above the stator (different make and model of motorcycle): significantly cooler with the series R/R relative to the shunting. Ah... Just found the link:

Series Regulators for Enhanced Stator Reliability

Scroll down to reply number 2, and have a look at the thermal imaging photos of an Aprilia motorcycle with the two types of R/Rs under comparable ambient conditions.
 

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I've actually seen that thread before, cool! Good to know you've gotten yours as a series-type, I'll probably switch mine over whenever I get around to finding some used ones on eBay
 

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Discussion Starter #20
Here are some oem V/S Caltric comparison pics.

.4 ohm across the leads. Infinite to the case.

So, it starts off well.
 

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