OK, thank you in advance for your willing spirit, and welcoming my as a guest on your forum. I'll try to provide as much pertinent detail as I can, please ask if I've left out anything. I'm trying to sort through simple physics, opinion and internet lore. Some of this detail is too much- but I'm hoping I can be clear for the non-moto types as well.
First, the bike began as a 2003 KTM 525 MXC. It's a desert-racing, enduro dirtbike that someone has licensed for the street. KTMs are known as "ready to race" and are built for lightweight and horsepower. The bike has CDI ignition timed by a weight on the flywheel that sends a pulse to the cdi box via an ignitor coil. Pretty standard stuff.
The stock electrical stuff is a stator, which is stationary and the magnet-laden flywheel is attached to the crankshaft and encloses the stator.
The stock stator looks like this:
Notice it has 8 poles of varying quantities of wire in the coils. One pole appears quite different from it's 7 friends- as I understand it, that s the AC coil. In stock form that coil creates energy to power the cdi box (for spark) and the headlight circuit. That means in the event of a battery failure, the bike will still run enough to ride, but will not charge the battery, eventually resulting in the loss of electric start ability. But will still kickstart and run. The DC side is run through a regulator/Rectifier for DC battery charging and accessories.
OK so far?
This system puts out an estimated wimpy 35 watts. It's just enough to do the job without adding weight and expense, and is simple enough to offer uncomplicated reliability.
Along comes the crowd, myself included, for whom nothing is good out of the box. We have to- COMPELLED to modify. One modification is a headlight that exceeds a single candle on a windy day. My personal choice is the Trail Tech Extreme Race Light, 95 watts of HID . It's a LOT of light. I'm old, my eyes are old, and I can't see a damn thing anymore. And it's cool- here, look:
I also add heated handgrips, two GPS (one including XM) and possibly a heated vest. Demand clearly outstrips supply.
The most popular modification is the TrailTech stator and DC modification. This involves replacing the stock stator and adding a new regulator/rectifier, then converting all non-ignition circuits to DC.- It's an easy modification, and here's a snappy of the stator TrailTech sells with it's friend the regulator:
Notice the 8 pole design, larger gauge wires filled further than the stock stator. Again, one pole visually different, which I assume is the AC pole to power the cdi box.
Trailtech makes it easy- almost plug-and-play. Dead reliable, this is the standard modification- done by thousands of riders worldwide.
But it's not enough power, Scotty. TrailTech claims 100 watts, but I suspect it's something shy of that. If I run all three lamps of my bitchin headlight, I'll discharge my battery. I have a digital voltmeter on the bike to monitor such things- voltage drops to around 11.2 to 11.7 at speed, at idle speeds insufficient to even keep the lights on.
It breaks my heart.
So- along comes an alternative. A few years ago, a company called ElectroSport began creating 3-phase systems for dirtbikes. A 3-phase system is most commonly found on street bikes, and they have a greater power demand, and care less about weight. Electroposrt began selling it's products and just as quickly began to have serious problems. Fried and boiling batteries, non-start problems, including one that would cause the bike to fail estarts, but work fine with the kickstarter (more on that later).
Electrosport claimed a manufacturer had substituted components of a lower quality without their approval, and this caused failures in regulation, etc. It ended up being a nightmare. Finally, one EE was hired to help out, and he did, but t was too late. The reputation of the company was shredded, and it was eventualy sold in shame.
Fast forward a few years. The EE that was brought into help Electrosport has started his own company creating 3-phase power systems. As I lust for power, I decided to try them out. EE has assured this system is similar to, but improved from the Electrosport system. I'm a commercial photographer by trade, and I like to help fledgling businesses get going, so I offered my services.
Here is what the new system looks like (beautiful photos no?):
and the regulator/rectifier- clearly far more robust with greater heat-dissipating ability:
I installed this setup on the bike and fired it up. PLENTY of power (Scotty)- this thing must have Dilithium crystals in it. With all demand on the system, it still provides 14.5-14.8 volts at speed, and just over 12v at idle. Perfect, right?
Well, maybe. My first long ride with the system failed at mile 113, between Palmdale and Barstow. Subsequent troubleshooting at home led to no-spark issue, which led to a failed AC pole. EE claims it a manufacturing defect, the first he's had in over 500 units.
OK, it happens.
But here's where it gets more interesting, and more internet-based chatter. And, frankly the reason for this winded post.
Notice the 12-pole design? There's another player online who makes highly custom and very expensive 3-phase systems. He eliminates the AC pole completely, and runs the entire system on DC. His claim is that the design of the stator- it's 11 DC poles- is inherently unstable and "unbalanced". He claims a system like this can never be relaible and is based on flawed science.
Do you agree with this analysis? Is the number of poles a factor when creating a reliable power system in three phase?
Further, notice the AC pole is smaller than the previous versions? This stator will start the bike using the electric start MOST of the time. If the battery is at it's peak voltage, and the fuel/air mixture is just right, it fires up like a champ. But if the bike needs to be cranked a bit more, dropping battery voltage, I have to resort to the kickstarter, which will turn the motor faster thus providing more AC power to the cdi box.
Do you believe the AC pole is too small to create enough AC for reliable ignition at lower (estart) rpm?
Could another pole be used to create more AC- use two poles instead of one? And (bonus points) could that be wired in a way to provide redundancy in the case of a (another) single-pole failure?
Whew.
Here's a pretty picture of me actually riding:
Thank you in advance for your thoughts, and please post questions- I'll do my best to answer.
