KDXRIDER.NET

Has anyone converted their AC charging system to a DC system with a small battery? I have 24hr team race coming up and switching over to an HID (needs clean DC power) headlight always seems to be a good idea about now.

I know people (baja, trailtech) sell kits for other bikes, would one of those kits pretty much have all you need to switch our bikes over? Maybe just swap out our reg/rec for a DC one and add a cap/battery?
http://trailtech.net/regulator_rectifier.html

You'll need the rectifier/regulator and a battery (with associated wiring) to make it work. You'll also need an aftermarket lighting coil to pump out enough juice to charge the battery after its rectifed. A lower wattage HID light would still be preferable though.

I am trying to remember if the lighting coil is grounded to the block? If so I need to "float" the ground and only have it hooked up to reg/rec I think.

Yeah, its grounded to the stator plate. Unscrew the ground, cut the eyelet off and solder/heatshrink a new wire onto it and fiddle it thru the existing grommet/wire cover and upto the regulator/rectifier and you should be good to go.

Re: Floating, cutting, soldering and stuff...

Uh..why?

You need both legs of the stator to rectify the AC to DC?

m0rie wrote:You need both legs of the stator to rectify the AC to DC?

Yup, from what I hear anyways.

Otherwise I suppose you would still have AC going into the block and only trying to rectify one half of it......

There is a pretty big annual 24 hr race here at Maplesville, AL.
Quite a few of my riding buddies have been involved or raced.
Not me, but I might do Iron Man on the mighty KDX next year (No, not really)

Bike lights are good and necessary, good bike lights are really helpful.

However, all the teams have gone to great lengths to have helmet lamps or battery powered headlamps in addition to the motor powered headlamp. There were all kinds of creations there, from $400 purpose built helmet lamps to automobile Zenon lamps fiberglassed into the helmet and powered by a battery in a fanny pack.

The consensus was that a rider REALLY needed both.

Have fun

We did the race last year, I had my UFO twins running off the bike and a 35w Cyclops helmet light running off a battery on my chest protector.

This year I plan to have the same helmet light setup, but I would like to run the new UFO "Halogen Ray" headlight with a H4 halogen bulb for sure. But would like to run a 35W HID instead. You can get quality H4 HID bulb/ballast setups for $80 now and I would swap out the halogen.

HIDs need reasonably clean DC power to run, so a rectifier and maybe a small cap are needed.

One time I was wearing and AC/DC shirt (you know, the band) and my grandfather commented it, asking if it somehow meant something about homosexuals.

Apparently, to him, AC means 'Alternate current', which would be homosexual, and DC as 'direct current' meaning a straight person.

So when I saw the title, Possible to convert AC to DC, I immediatly thought of that and figured you were attempting to bring a lesbian chick to the straight side

sorry just had to share that

Re: 'You need both legs of the stator to rectify the AC to DC?'

strider wrote:Otherwise I suppose you would still have AC going into the block and only trying to rectify one half of it......

My point is (was), it depends.

Full wave? Half wave? Voltage doubler?

What it depends on is the rectifier type, the output desired, the voltage loss you can handle (and still get the desired output).

And...after you rectify it, you still have to regulate it. A battery will 'regulate' somewhat. You end up with a good bit of 'stuff'..and it all has to fit somewhere. That..and your basic one-each float battery won't float so good when the bike is upside down.

Keep in mind you're dealing with something like...what...less than four amps with the OEM coil. You don't have a lot to lose.......more likely not enough to start with.

This may be helpful...

Notice the word 'peak'. That's not peak TO peak.....

What do you think Canyn, these two parts and I am good to go?
reg/rec http://trailtech.net/regulator_rectifier.html
and a cap? http://trailtech.net/batteries_capacitors.html

I have a rewound coil (70w?).

I don't have the smarts to know by the numbers if it would work.

Well...I don't know the numbers anyway.

I don't see how it would work..but I can't prove it to you.

It says 'regulator/rectifier'. Given the input from the souce coil, I don't know the loss of that unit, how much regulation there is, what its regulated TO. A 'good' battery charge voltage I would presume. That's going to be around 14VDC. The unit is rated at 150W..but that's simply it's maximum output..NOT what it puts out regardless of input.

Can the device listed handle 100V+ input? Is it meant to/able to charge a battery?

Why use a battery at all? For light use without the bike running?

Using a basic load as an example......40 watts at 12V is 3 1/2 amps (more or less). The battery you listed is 1.2AH. Hook that up to a 3 1/2 amp draw..and the battery's going to be dead pretty darn quick.

Then you consider that, while different battery types (wet/float as opposed to AGM for example) 'like' different draw-down levels and still be useable, NO battery wants to be sucked 'dry'.


ha ha ha...I'm so funny.

'Dry' meaning amp-wise..not electrolyte-wise.

It's more like a 20% drawdown for a decent number of recharges to work.


OK...back to reality..I don't know. I'd bet not.

Buy one, wire it up, let us know!!

**edit**
Reading through some of the install/spec sheets brings to mind this rather important (read: critical) note. These HID light setups are generally being run on AC-DC converted systems, yes. BUT..they are using stators with muliple coils...not A coil. That's a big fat distinction.

Well circumstantially Baja Designs sells a dual sport kit for the KDX that includes a rectifier/regulator and battery. The instructions tell you to use a rewound hi-po lighting coil and to float the ground for the rectifier to work. Even then the directions advise that the lighting coil is going to be on the edge for charging the battery with the lights on. YMMV and all that jazz.

http://www.bajadesigns.com/2005%20Web%2 ... lassic.pdf

What i'd be worried about is not so much the running draw from the 35w HID lighting as the draw from the ballast igniting. I bet its at least double the running running draw. Might be enough juice to keep it running...but not enough to get it lit in the first place.

Hmm, no battery for me, hopefully just a capacitor listed on trailtech's website to smooth things out a bit.

The input surge for the ballast I want is about ~40% more than running draw.

e.g. ~3a running draw ~ 4.5a surge draw

It might be double..but it's short!!

...you could carry a group 27 in your backpack to do the starting...

The whole idea of mixing this-n-that, coming up with a working solution by picking parts out of a catalog is almost certainly going to have brazillions of problems.

If what one wants is a system that works...buying said system is the way to go about it.

Certainly it's possible to design/assemble your own 'system'. If that's your choice...good luck and moh powa to 'ya!

ha ha moh powa...there I go agin!!

Considering draws and things... a battery is an excellent source for lots of current fast!

Not to pick...but 4.5 is a 50% increase over 3.0.....just in case that figure figures into things......

I don't lay up my own carbon fiber petals..

I don't injection mold my own air guide.


....I just buy a DeltaForce III.

I don't make smart a$$ comments and then delete them...wait I just did, and got caught... Sorry 'bout that CC.

...which leaves me wondering where I thought I read the ghosty stuff.

SmartA$$ is good!

Well...I keep telling myself that. Keeps me from jumping off the nearest tall building when I thusly consider my great worth to mankind.