KDX qs

[EncyclopediaRonnie]

hey guys i wanna know how kdx electrical system works ie what powers the head light when the motors running. if some1 has the electrical system wiring diagram that would be unreal. i wanna try get some lighting action going on my kx winter time trails ;)

im to the impretion its just a coil that drives it however i wanna know what coil. what it conects to etc

cheers

 

[helio lucas]

check out the kdx forum.
on the top you have a stickye thread about it :cool:

 

[sr5bidder]

find the yellow wire and take it to one side of the headlight and the other side take to ground I have a deans ultra connector (typically used in RC car batteries) so I can remove the light easily, whenever my bike runs I have headlight (no switch)

this is for 95-06 kdx200/220

 

[EncyclopediaRonnie]

find the yellow wire and take it to one side of the headlight and the other side take to ground I have a deans ultra connector (typically used in RC car batteries) so I can remove the light easily, whenever my bike runs I have headlight (no switch)

this is for 95-06 kdx200/220

does this come from the stator or a coil? its actuall gonna be on my kx but its what i want light when it makes noise none when its off

 

[Dirtdame]

You would need to add a lighting coil to your stator on the KX. Steahly products carries some lighting coils for MX bikes to convert them over to being able to power lighting. There may be other companies who carry that kind of stuff too.

 

[EncyclopediaRonnie]

You would need to add a lighting coil to your stator on the KX. Steahly products carries some lighting coils for MX bikes to convert them over to being able to power lighting. There may be other companies who carry that kind of stuff too.

if i used a capacitor would i be able to steal power from the ignition coil?

 

[Rich Rohrich]

Read it again, slowly this time :)

You would need to add a lighting coil to your stator on the KX.

http://www.electrosport.com/vehicles/dirt-bikes/

 

[dirt bike dave]

FWIW, low output systems like the stock KDX system were mainly useful to make the bike legal for enduros, as required by some sanctioning bodies.

If you actually intend to ride at night in the woods and see where you are going, you will want more power.

 

[EncyclopediaRonnie]

Read it again, slowly this time :)





http://www.electrosport.com/vehicles/dirt-bikes/

i read it and understood it, now i want a way around it lol when you rack brains enough you find the dodgey not proper but will work way ;) i know my stator sends a 45- 50 volt signal, well at leastso says my multimeter so the key know is determining if the power is stable and has high enough amperage. if i can then ive just got to regulate the power and use a small battery or capacitor

 

[reepicheep]

batteries and capacitors can't add power. They can store it temporarily and return it.

So saying you will add a capacitor to make your bike output more light is like saying you are going to add a spring to make it faster. You might, but only for short periods of time.

The one place it might help you is if you can find a low power HID. A HID has a high initial startup current, but then uses power pretty efficiently (like maybe 1/2 to 1/3 of the current a normal bulb will use). So a big capacitor might get the HID started, and the bike can then sustain it.

But I doubt it. Those KX's are lean and mean. My kid's early KX-60 actually came with two coils... but I think most KX's didnt.

 

[Acblind]

What if you used a battery as the main power supply and then just used the stator as a trickle charger for it. You would need to recharge the battery after a couple rides or so, because the stator probably wouldn't be able to keep up with the drain on the battery, but it would at least give you a little more time than just the battery alone.

Combine this with the HID lights that reepicheep mentioned and you should have plenty of light power, for a resonable cost.

 

[reepicheep]

Batteries are typically rated in "Amp Hours". You take the capacity of the battery, divide it by the number of amps you draw, and the result is the number of hours it will run before the battery is discharged.

A small motorcycle battery is about 4 amp hours. A standard HID is probably pulling 15 to 30 watts at 12 volts (15/12 = 1.25 amps, 30/12 = 2.5 amps).

Therefore, a small motorcycle battery could run the HID for between 3.3 and 1.6 hours provided it started fully charged. Also, lead acid batteries wear quicker when deep discharged like this. You would also need a recharging device for the battery between rides, a traditional battery charger would bake it if left connected, a float charger would take a long time to bring the cell up to power (if ever).

If it were me and I wanted to go down this road and homebrew, I would probably try and find a lithium ion battery drill, and use it's batteries and chargers to run the HID, leaving the battery pack as "quick swap". In fact i would probably buy two complete drill kits. One would stay a drill for when I want to drill. The other would have the "handle" recepticle part cut up to become the battery socket on the bike, and I'd keep the rest of the drill as "parts". Then both batteries would be on chargers and come along for the ride when I want a lighted ride, and be available for the drill when I need a drill.

I probably wouldn't even bother wiring it into the bike.

 

[EncyclopediaRonnie]

What if you used a battery as the main power supply and then just used the stator as a trickle charger for it. You would need to recharge the battery after a couple rides or so, because the stator probably wouldn't be able to keep up with the drain on the battery, but it would at least give you a little more time than just the battery alone.

Combine this with the HID lights that reepicheep mentioned and you should have plenty of light power, for a resonable cost.

this is sorta what i wanna do. but use the stator to chrage a capoacitor and the capacitor to feed the light basically to take the load of the stator and nothing else i expect it to hold no charge. im wondering where i can get a regulator or something to step the 40-50 volts im geting now down to dc? ill try up load a pic of the wiring diagram for my bike maybe it helps

 

[EncyclopediaRonnie]

so top pick is of a voltage regulator/ rectifier for a 199 kx 125.

bottom is my bikes wiring diagram im thinking of grabing power from the B/R, R, W leads from the exitor coil before it gets to the ignitor also using a power diode just so curent dsnt flow the wrong way. hooking that up to the reg/rectifier. then feeding that to a small battery / capacitor then to a halogen globe or HID if i can pick up a cheapie.

thoughts

 

[reepicheep]

Again, a capacitor can't add power. It can only store it, and it cant store it for long (seconds). A battery is like a big capacitor, but it can't absorb energy as quickly, or deliver it as quickly, but won't self discharge as quickly as a capacitor either.

The maximum power that your KX coil produces is a factor of the strength of the permanent magnet field around the coils, the number of turns of wire on the coil, and the RPM of the motor. It will produce a sine wave for each engine rotation, so at low RPM it will be about 16 Hz, going up to maybe 150 Hz at high rpm (assuming something like a 9000 RPM redline).

Kawasaki ignition coils don't have many windings and don't produce a lot of power. That's why Kawasaki enduro bikes have a secondary coil on the stator, called the lighting coil. It is much bigger then the ignition coil, the ones I have pulled (KX-60, KDX-200, 1971 F8 250) were at least twice as many windings.

So I think the problem is the power just isn't there, and a capacitor won't put it there. You need another coil.

As I said before, my sons 1990 KX-60 *did* have a lighting coil from the factory... not hooked up to anything. In later years, they dropped the coil, but left the mounting points. Maybe your KX is the same way, and you can get a bolt in coil from Ricky Stator or somebody, and that would be what you would want to draw power from. It shouldn't cost more than about 1 HP.

You can buy generic voltage regulators on ebay that will work well, but most are "shunt" regulators. They don't have a high voltage input that stays high, and a 12 V output that stays at 12V (like you would expect)... instead they go basically inline with the voltage output and shunt excess power to ground to maintain 12V on both the input and output. So if you drop one of those inline with the coil output, the rest of the bike will see like 13.8V DC instead of whatever the bike does now. I'm not sure what the voltage is by default (I think it's like 20 some volts AC on my KDX, but don't know for sure). I don't know if your coil and CDI will work like that.

 

[EncyclopediaRonnie]

i know that a cap will not store charge like a battery i dont want it to i onli want it to charge and drain so the load source isnt as heavily on the stator/ coil directly. if that makes sense. i beter suss out if my bike has 2 coils lingering there too i might get luky as it is a 93 model.


i have to check it properly but i was geting no ac power and 40- 50 v dc. this is why im thinking if i reg it and run a diode to keep it from interfering with the other circuits other than exessive drain. i may sneak away

 

[Acblind]

I think your best bet is to build a battery powered HID light set up completely independant from the bike's electrical system. It's the second best option you have at this point, the first being a secondary lighting coil. I like the idea of using a power drill for a batery/holder on the bike, but they make small li-on battery packs that are rechargable and will do the same thing.

I know they won't be as bright but you may also consider an led lightbulb. They draw next to nothing and will give you more time between recharging the battery.

 

[EncyclopediaRonnie]

maybe im gonna have to start exploring this tooo, tomorow im gonna test what voltages i get from my coils if i can get good voltage im gonna try and reg it. if i pull this off i will do a write up for every1 wanting a cheap easy way lol