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New guy with 07 450 problems

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I've searched around and havent found anything. I'm a new guy to the forums and have an 07 kx450 and have been having issues the past 2 months and cant pin point my problems.

When my bike gets hot (race speed hot) it will die like I fouled a spark plug and wont start back up. I have to let it cool completely down (20-30 minutes of waiting) for it to start back up.

First i thought it was the little stubby gas cap breather (which i trashed and put the stock hose back on)....did fix it. Second i pulled the carb and cleaned it top to bottom. Nothing.

Now I'm thinking something electrical, but dont know where to start. I dont want to start pouring money into parts that arent actually needed if i dont have to.

Anyone else ever had problems that when the bike gets hot it just shuts off? If so, what happened to yours and what's the fix?

Thanks.

Zach

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thanks for the quick reply. wouldnt that just cause it to not run at all? or just under the extreme heat?

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thanks for the quick reply. wouldnt that just cause it to not run at all? or just under the extreme heat?

Don't get me wrong, it could be something else.

Easy way to check: when it dies, check for spark. If it comes back when cool, it's the stator or the CDI. If it's the CDI, you can pack it in ice to be sure. But it won't be.

Yes, you can test them: take off the stator, put a meter on it, check for continuity. Put it on a hot plate (not directly) and get it hot. Meter it again.

Many times, a 'smoked' stator will have burn marks on it.

A brand new, better one is only $130.00

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well, i havent pulled the stator off yet due to trying a couple of other things before spending the money on the stator, and that not possibly being the problem. Ive ridden twice to see if i can get the bike to die on me again...but i cant get it to die. the only way i can get it to is during a race (harescramble). but i did notice the two times i rode, i was boiling the gas and gas cap hose seemed to bairly be breathing. when i got the bike, it had a hose with some sort of brass ball valve type thing about half way up the hose. not sure how to describe it, but theres a little BB inside and when enough pressure is pushing on it, it blows that BB up enough to let some air breath out the hose. if that makes sense. thinking of putting just a regular vent tube on the cap where there are no restrictions in the tube other than the fuel cap. ever heard of issues like this? also, the stator wouldnt cause this?? the bike is acting like its vapor locking when it does die. thoughts?

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well, i havent pulled the stator off yet due to trying a couple of other things before spending the money on the stator, and that not possibly being the problem. Ive ridden twice to see if i can get the bike to die on me again...but i cant get it to die. the only way i can get it to is during a race (harescramble). but i did notice the two times i rode, i was boiling the gas and gas cap hose seemed to bairly be breathing. when i got the bike, it had a hose with some sort of brass ball valve type thing about half way up the hose. not sure how to describe it, but theres a little BB inside and when enough pressure is pushing on it, it blows that BB up enough to let some air breath out the hose. if that makes sense. thinking of putting just a regular vent tube on the cap where there are no restrictions in the tube other than the fuel cap. ever heard of issues like this? also, the stator wouldnt cause this?? the bike is acting like its vapor locking when it does die. thoughts?

It is a common problem for the 'filtered' or 'one-way' tank vents to fail. Try a regular piece of hose only.

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I'll try that tomorrow when we go ride. Hopefully thats all ill have to do. I've been thinking of getting on a new 11 model, but want to get this bike fixed before i sell it. I dont feel it right to sell a bike that kind of runs to someone, with them thinking its a ready to go bike.

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so i've got the dying problem fixed. put a regular piece of hose on and she's running good. I did have the hanging idle problem out on the trail and got to messing with my fuel screw. the only way i could get it down was 4 turns out. I know it should be somewhere between 1-2.5 turns out, but 4? Is this something to be worried about? I cleaned the carb a few weeks ago, and flat ass forgot to see what jets were in the carb.

The bike runs great now, just dont know if i should be worried about the 4 turns out or not on the fuel screw.

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so i've got the dying problem fixed. put a regular piece of hose on and she's running good. I did have the hanging idle problem out on the trail and got to messing with my fuel screw. the only way i could get it down was 4 turns out. I know it should be somewhere between 1-2.5 turns out, but 4? Is this something to be worried about? I cleaned the carb a few weeks ago, and flat ass forgot to see what jets were in the carb.

The bike runs great now, just dont know if i should be worried about the 4 turns out or not on the fuel screw.

You probably need a new 'slide plate seal', as when it goes bad, you get a lean condition (hanging idle, fuel screw way out).

$6.00 part.

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