no spark

[mod440ex]

I was riding today and all of a sudden my wheeler dies. I thought i fouled my plug pulled it and checked the spark, and nothing. I tried another plug and same thing. I tried another coil i had, and still nothing. I checked my rev box and tried my buddies off his 400. I checked evrything i could think of. I f anybody has had this problem and knows what to do to fix it please help me out.

[GPracer2500]

Since you've already tried swapping coils and CDIs, I'll guess that your stator has failed. A service manual will outline how to test it to be sure that's what's wrong.

[mod440ex]

where is the stator

[GPracer2500]

It's bolted to the inside of the left side case cover.

[mod440ex]

I thought the stators where for charging the battery. I looked on rickystator.com and it didnt say anything about spark, just about more watts going to the battery.????

[GPracer2500]

There are actually two seperate windings that make up the stator. One of them is the lighting coil for charging the battery (or directly running the lights on bikes that don't have a battery). The other is called the exciter coil. It generates power used by the CDI/ignition coil/spark plug.

Here's a 200w RickyStator stator for a 400ex. Notice that two of the windings look different? The whiteish ones are the exciter coil. All the others are for lighting. Often the exiter coil portion of the stator will look different (color, size, etc.), but not always.

http://www.xrsonly.com/data_UD/rickystator/RS-TRX400EX.jpg

You can have a lighting coil that works fine--charges the battery, lights the lights, whatever. But that doesn't mean the exciter coil is working.

Another thing worth mentioning is that the pulse generator could be bad. In the above picture it's that seperate black thing in the upper right hand corner. Pulse gens and stators usually come as a unit. The pulse gen's job is to tell the CDI where the crank is at in its rotation. On the flywheel is a little magnet. Every time that magnet passes by the pulse generator a signal is sent to the CDI which tells it to initiate the spark. If the pulse gen is inoperable then the CDI might not know the engine is spinning.

Summery: The exciter coil charges the capacitor in the CDI. At the right time the pulse gen tells the CDI to rapidly discharge its power to the ignition coil. The ignition coil then fires the plug. The lighting coil side of the stator has nothing to do with it.

[mod440ex]

It is the stator. I pulled the cover off and when i was trying to pull my flywheel off, i took some of the bolts out of the flywheel that hold the starter clutch and i forgot to tighten them, what an expensive mistake(lesson learned)

[400excaleb]

its the stator, i had the same problem, i bought the a rickystator stator from jl atv products. it was $150 and it comes w/ 1 year warranty and i have had no problem since i got it but if u want to check to make sure that is what it is for sure when follow the wires coming out of ur case which is the stator wires and they lead to the back of atv above the battery and check for spark there