hey everyone-lately ive drove myself nuts trying to start my atv only to find the spark plug doesnt spark. what causes this? its a brand new plug and the ignition and killswitch are fine. basically it seems as tho the electrical system before the plug is fine, but no power is sent to the spark plug. i looked and theres this black cylinder like thing with wires on the top and on the bottom one wire leads to the spark plug cap. is this the part i need? if so what is it called and any reccomedations where to get it? thanks everyone

 

that sounds like the coil , it might be loose or have a bad ground . if you had a test light you could unplug the wires coming into it and try to turn the motor over while checking each wire .... what kind of bike is it

 

its a sundiro atv but is the coil the cylinder thing?

 

if the spark plug wire goes to it then yes , if it is lose or the ground is lose then it want start that might be your ploblem

 

The coil will have two wires going to it. One should be green and the other is probably black w/yellow stripe.
Ensure the green/ground is a short to the frame/engine. Then check for a voltage going to the coil on the other wire when cranking.

If the voltage is there when cranking and still no spark, it is the coil. No voltage, means bad CDI.