No spark for a 1987 moto 4 350 atv - Yamaha 2004 Warrior Base

remove spark plug,put wire back on it,ground end opposite the wire end to motor metal.crank over the engine and see if plug is firing,should see blue or yellow spark close to the electrode.i assume your motor is cranking over,right?

Hello, Get a FACTORY service manual and FOLLOW it to the LETTER and DO IT RIGHT!

There is on most new ATVs an idle control valve it can be vacuum or electric i think yours is Electric its like a little valve with a spring it could be stuck or faulty depending on what the unit is doing .

Idle Air Control Valve ATV CF moto Valve UTV 400 500 700 HiSUN MASSIMO Hsun

Sounds like you have a bad igntion switch or other electrical gremlin somewhere. If this is something you bought like this, then I would get a service manual with a wiring diagram and ensure the wires on the key switch are in the right positions.

The coil is last component in system. Need to verify other components in system.

oppss ... you need factory service manual for cdi and other resistance specifications

it probably is the interlock switch/ the black square with 2 small green wires and to large reds.replace that and should run.just bypassed mine and know it works.have fun