Hello i recently bought a used atv brought it home and found out there was no spark when i started it up, bought a new ignition coil and a new CDI unit and got spark later i started it up it ran for a few seconds then died and turns out that it has no spark anyone have any clue why... I checked the CDI and it did not have any burnt smell any ideas....

 

If you fit a new CDI to any quad, you must check that the earth wire to the CDI is good or you will burn the new CDI out. They often show no sign of damage and die very quietly. Other possibility is you have either an intermittent bad connection in the ignition circuit or a problem with the stator, they can sometimes work, sometimes not. An overcharging voltage reg can affect the CDI, even though they are usually on totally separate circuits. However, check all those wires to the CDI out before spending any more money. Lots of posts on here about how to do it, the help diagnose stator sticky in the Chinese engine section of the forum is a good place to start.