07 kx250F overheated - now engine cuts out

BANNEDFROMBAJA

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My buddy's has a problem with his kx250F
He was at a riding clinic a few weeks ago and his bike overheated. When his bike cooled down, it seems fine and started up no problem. But about 5 minutes in, it sputters like a fuel problem then dies. He waits a few minutes, the bike starts up, but the issue repeats itself a few minutes later. We did a cursory trackside inspection of the fuel system, and it appears fine.

It feels like a fuel problem, but since it occurred right after it briefly overheating, we think its gotta be something else.

What do you guys think?
 

Racer21(Roberto)

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I think it's a cooling problem, because i think the Piston is overheating getting really big, and siezing. and than once it cools down and the piston shrinks, it will start again. So some sort of cooling problem i think.

Im not sure though, I just took a few months of small engines, but thats what i think it is. Can anyone confirm this???
 

troyharper

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The problem is,


































































































ITS NOT A HONDA!
 

Racer21(Roberto)

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Well we all know that!!!

But come on! i thought i would solve my first Dirtbike problem on RDC! it has to be cooling system.
 

Total Loss

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Any white smoke?
Coolant level dropping?
Could be a blown head gasket or warped or cracked head.
When it heats up- everything expands and enhances the problem.

Ask troyharper how good the casings were on the old Cr's.
Had my share of cracked casings and eaten away magnesium water pump housings back in the day.
Hondas are not foolproof either. (I do have 2 in the garage though)
 

AzDzrtRcr

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Its in the head or piston, either way, plan tearing it down. There will be no quick fix,sorry.
 

Bajades

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My buddy's has a problem with his kx250F
He was at a riding clinic a few weeks ago and his bike overheated. When his bike cooled down, it seems fine and started up no problem. But about 5 minutes in, it sputters like a fuel problem then dies. He waits a few minutes, the bike starts up, but the issue repeats itself a few minutes later. We did a cursory trackside inspection of the fuel system, and it appears fine.

It feels like a fuel problem, but since it occurred right after it briefly overheating, we think its gotta be something else.

What do you guys think?
The exact same thing happened to a friends 06 KX250F. The bike would run fine for a few minutes and then would die. Let it cool off and it would start right up. We pulled the carb jets, fuel lines, and float bowl and found nothing. He repeated this scenario about 4 or 5 times before the bike finally seized for good. Turned out he had installed the oil filter backwards (easy to do), cutting all oil flow to the top end, and the bike was seizing. Completely destroyed the upper end of the motor.:(
 

BANNEDFROMBAJA

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BANNEDFROMBAJA

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The exact same thing happened to a friends 06 KX250F. The bike would run fine for a few minutes and then would die. Let it cool off and it would start right up. We pulled the carb jets, fuel lines, and float bowl and found nothing. He repeated this scenario about 4 or 5 times before the bike finally seized for good. Turned out he had installed the oil filter backwards (easy to do), cutting all oil flow to the top end, and the bike was seizing. Completely destroyed the upper end of the motor.:(
thats what we did pulled the carb apart and cleaned it out, the bike started fine than went riding and shut off after a few min riding, no smoke, coolant level not dropping
 

referman

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Its overheating cuz the Hot Start cable isn't set right. I'm convinced Kawi hot start needs to be replaced with a pull button and eliminate the cable all together. And NO TROY.................Its not becuz its NOT a HONDA!!! LMAO. You can play with the jetting, rebuild the carb, clean it, blow it, replace your pump...........but in the end, it overheats becuz it's running very lean. That's my take...............from experience and 3 pistons!!!!! But then again, I own a 450 not a 250 so....hmmmmmm.

LVJames....
 

referman

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Button replaces the cable...
 

referman

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Here it is again...
 

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BANNEDFROMBAJA

2317 Cherimoya Drive Suite A Vista, CA 92084
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thanks for the info im passing it down to my friend and see if any of this fixes the problem
 

57Racer

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Could be a warped head (depending on how hot he got it) or fried gasket. Get it smokin hot once, fries the gasket and you lose some compression (causing sputtering or lean pops), then when it cools, all good. Rinse repeat.

Just guessing anyway...

Reminds of the 2stroke days when you overheat there was a rubber head gasket purposely made to melt first. By doing that it would melt, you would lose compression, stalls the bike, prevents further destruction of the motor.
 

BANNEDFROMBAJA

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so he fixed the carb then did a race and by the 2nd lap the bike is in the truck and headed back home.

he said he tore the bike down and i guess it was the stator


now the next question is does anyone have A 2007 KX250F STATOR
they wana sell
i know you can buy a new one online but maybe someone on here has one and wants to sell it :)
 

Icon 1

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The problem is,




ITS NOT A HONDA!
Wow can cant imagine what this would be like if you happened to be in Mexico all ready to race the Baja 1000 and defeat the Giant RED Dragon and something like this were to happen. But no one would actually put themselves in that situation so no worries... ERrrrr... uhhhh.... well....
 

BANNEDFROMBAJA

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Wow can cant imagine what this would be like if you happened to be in Mexico all ready to race the Baja 1000 and defeat the Giant RED Dragon and something like this were to happen. But no one would actually put themselves in that situation so no worries... ERrrrr... uhhhh.... well....
thats why we race HONDA in SCORE but the green bike is the practice/local races bike
:cool:
 
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