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2015 yz250fx won't start

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I purchased a yz250fx back in January. I have raced the bike this season in the 4 stroke A class. The bike done great until the last race of the season. I was in the lead and the bike was running good and just blubbered and cut off and hasn't cranked back since. I took apart all the electrical connectors and cleaned them, checked the fuel pump and cdi by putting them on another yz250f, and checked it for spark. All of that was good. It seems like the bike has lost some compression. The bike probably has 100 hours but has ran perfect with no problems. It literally was running great and just shut off. I don't know what to do. Any ideas from anyone? Thanks in advance

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So did you prove the pump and cdi were fine ?

 

Did you clean or replace the pump filter? (every 20-50 hours....) Are you filtering your gas into the tank?

 

do you have spark?

 

Have you adjusted the valves?

 

Have you done a leakdown test on the head to see if you have a leaking valve seat?

 

Have you pulled off the stator cover and inspected the pickup for magnetic debris or a loose stator?

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The fuel pump and cdi worked fine on the other bike so there good. It has good spark as well. I haven't checked the valves or done the leak down test. It was running fine and just cut off. It didn't smoke or make any weird engine noise when it happened. Which kind of makes me think it's something electrical. I will check the stator tomorrow and if that's not it I'll check the valves next and see if I can find someone to do a leak down test for me.

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I just checked my valves. There right where they need to be. .012mm on the intake and .17mm on the exhaust.

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I checked the stator as well and it was tight and didn't look worn at all

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hey man you ever figure out the issue with your bike. I have the same bike and the same problem. 

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Crash 214, how about you, it’s been been a year since your post, what fixed it? 

My bike suddenly won’t crank over, swapped batteries, no help, just getting started with the troubleshooting.

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