cr250 not starting

Bike ran fine all day today and then stopped riding for an hour or so and went to ride again and the bike started right up. I kept the revs up while sitting and then let it just kind of idle and it died. It wouldn't start again and gas was leaking out of a tube coming from the carb. I pulled the plug out and it was soaked. It seems like it's running rich but I don't get how it could go from running mint to not at all. I am also thinking it may have something to do with the oil I am using because the guy that had it before me used honda and I am running bel ray but I doubt that is the cause. Any ideas?

I pulled it apart again and noticed the plug has a nice blue spark but is only sparking sometimes. I will spark on one kick but then wont spark for another like 8-10 kicks. The plug is black so i'm thinking this is the cause but would a fouled up plug have a good spark but only spark sometimes?

EDIT: Just did another test and help the spark plug about an 1/8" away from the spark plug hole and it gave a nice big blue spark every time but, the spark was all over the place. It was jumping from the small bent metal piece on the spark plug (I think it's called the electrode) to the head. Maybe the gaping is off? Or is it supposed to jump like this?

Your needle and seat in the carb may not be sealing off to control the fuel level in the carb. When that happens you'll get the fuel from the vent tube off of the carb. It also will flood the motor with fuel, and be very hard to start. Usually a small piece of debris will get in between the needle and seat, and cause this problem. Sometimes it will pass on through. Sometimes you can lightly tap on the bowl of the carb to dislodge it. Sometimes the needle and seat or worn just enough to stick occasionally. Install a new plug and give it a try. It may still have quite a bit of fuel in the crankcase and be hard to start. Hold your throttle wide open and kick on it until it starts. Some people will pull the plug and kick the motor over to dry it out. That's ok, but make sure you plug wire doesn't jump to ground, make a spark and catch your bike on fire. I don't think you need that type of excitment.

I pulled it apart again and noticed the plug has a nice blue spark but is only sparking sometimes. I will spark on one kick but then wont spark for another like 8-10 kicks. The plug is black so i'm thinking this is the cause but would a fouled up plug have a good spark but only spark sometimes?

EDIT: Just did another test and help the spark plug about an 1/8" away from the spark plug hole and it gave a nice big blue spark every time but, the spark was all over the place. It was jumping from the small bent metal piece on the spark plug (I think it's called the electrode) to the head. Maybe the gaping is off? Or is it supposed to jump like this?

If you hold the body of the plug to ground (head), the spark will jump the gap to get back to ground. If you hold the plug away from ground (head), the spark will jump from the electrode to get to ground.

If you hold the body of the plug to ground (head), the spark will jump the gap to get back to ground. If you hold the plug away from ground (head), the spark will jump from the electrode to get to ground.

But when I hold the plug to the ground it only spark sometimes.

Also the kill switch doesn't work. The guy said it isn't grounding right or something. My dad thinks that has something to do with the plug not sparking when it touches the head. Could 2 wires maybe be touching and that is screwing up the ground? But, I don't see how the bike can go from running today to not running.

Are you testing spark with the "flooded plug"?

sounds like you just need a new plug. Sounds fouled.

I stuck an extra lawn mower plug I had in the boot and it sparks perfect. So the plug I have is bad. I'm going to pick up some more plugs tomorrow. I hate NGK so what would be the best?

Hate NGK? Remember your bike fouled the plug not the other way around. LOL That's like saying I hate No. 2 pencils. All pencils are the same it's usually the writer that's messed up. Plus NGK BR8ES are only $2 at AutoZone:)

if you use the racing plugs they tend to work a little better...at least for me. The BR8EG is what the bike calls for. its about 5-6 bucks but i think they are worth the extra cheese.

put a new plug in there, start it up, run it hard to clear it out, then pull the plug and see what it looks like.

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