Bashan 250 ATV - No Fire Issue: Replaced Ignition Coil, Module, Regulator & Spark Plug

Good morning, I have a problem with my Bashan. The problem is that I drove it and everything was OK but after switching off the ignition did not fire again. I replaced the ignition coil, ignition module, regulator, and spark plug. And I have a problem because there is a spark, the fuel comes in and still does not ignite which may be the reason. The spark is such an average I measured the current from the charging coil of the feeder in the module is about 20V AC. After attempting to light the quad, when I wring out the candles, there is some smoke in the head. Regards bashan250michal.

what could be the reason

Added after 12 [minutes]:

please help

The valves were checked for support. Maybe they need adjustment.

adjusted

Have you measured the compressions? Perhaps the rings have run out or the timing has jumped.

compression is good rings recently replaced the whole new cylinder

Fresh fuel? You can try the spray starter to squeeze into the air filter or poster as you have.

I tried with my dad

Added after 55 [seconds]:

and what could be the reason for the disappearance of the spark?

Ground problems or breakthrough cables somewhere. Even the candle itself can be guilty.

I also checked a new candle and I know that the mower works efficiently

guilty stator in the engine