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Jeremy R.
Jeremy R., Mechanic
Category: Motorcycle
Satisfied Customers: 9020
Experience:  15+ Yrs Factory certified technician and business owner.
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my 2004 Honda crf 250 x stops firing plug as soon as it warms

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my 2004 Honda crf 250 x stops firing plug as soon as it warms up
Hi, My name isXXXXX you for letting me try and assist you with your problem.
Have you done anything as far as any testing to see what's going on?
Customer: replied 3 years ago.

I looked at spark and Its not consistant and some times stops firing

Ok, Did you do this by laying the spark plug on the engine or with an inline tester? or something else?
And I assume it runs great up until it gets warmed up correct?
Customer: replied 3 years ago.

correct I checked with plug but It runs fine until warm

Here's the catch.
It could simply be a bad spark plug, so that would be the first thing I would change.
If you have done that then the most common culprit is the cap assembly on top of the spark plug. They do wear and stop working intermittently like you say is happening to yours.
The part number through Honda is 30700-KRN-670 and sells for about $49
If that doesn't fix it the second most common issue is the pulse coil on the stator assembly.
And that's about $475
So hopefully it's just the cap if not the spark plug.
Give that a shot and let me know if there's anything else I can help with.
Customer: replied 3 years ago.

Ive already changed coil assy Isuspected stator ploblems dose the parts cost that much and Is It that defacult to change Iwork on heavy equipment

Man if you work on heavy equipment this will be a walk in the park.
I used to work on heavy equipment myself.
The parts list I have shows $472.98
Part number 31100-KSC-671
It doesn't show a breakdown of the parts where you can buy it seperately.
That part number is XXXXX kit that includes the stator, and flywheel.
So check with a dealer to see if they can break that down. Certainly that would save you a chunk of money.
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