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Discussion Starter · #1 ·
I recently bought a 2003 raptor 660r that would not run I cleaned the carb and it started right up but whenever i gave it any throttle it bogs backfires and dies.
it is all stock with a k and n air filter and has all stock jets a positions. things I tried where disabling the parking brake switch and reverse switch i checked for any leaks in all off the intake boots and air box and i also cleaned out all gas lines and my petcock as well as my gas tank. none of that changed anything and so far it would only run with choke so i put in bigger jets which had no effect at all. anyone have any ideas or know what's happening. thanks for your feedback
 

· Master of the Electron
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Is the airbox lid properly in place?
What jet sizes are you running?
 

· Master of the Electron
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So "it would only run with choke on" - explain how it runs with choke on, in detail.

Did you remove and replace the emulsion tubes while cleaning the carbs?

Can you describe exactly the processes by wich you cleaned the carbs?
 

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Discussion Starter · #6 ·
I figured out that after adjusting the valves and getting a new carb I had low compression 100/180 also figured out that my coolant was milky so I took the hole top end of down to the jug everything looked great besides the head gasket was pretty warn I got new piston rings and gaskets now I am putting it back together to see if it works
 

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100psi is normal with the decomp mechanism, but as long as your head gasket was actually the culprit then you should be in better shape.
 

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O really I sall 180 online but after rebuilding it I had the same problem my next step is a new cdi
The manual says 180, and the manual isn't really wrong, but in the real world you'll see about 100psi with a properly functioning decompression mechanism. Probably didn't need to rebuild, but as long as you did everything correctly then it's fine
 

· Master of the Electron
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If you have spark your CDI is fine.

The autodecomp mechanism can limit a compression test to 80 psi.

My intuition tells me there's a 99% likelihood that this is a carb issue.
 
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Discussion Starter · #11 ·
If you have spark your CDI is fine.

The autodecomp mechanism can limit a compression test to 80 psi.

My intuition tells me there's a 99% likelihood that this is a carb issue.
the thing is I have tried every thing with the carb even replacing it. now it idles grate without choke it just keeps on bogging it wasn't the cdi I bought a new stator but i am debating replacing it do you think I could be a slightly bent valve that cant be seen unless taken out. here is the video of the problem
 

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that's not the problem with the old carb i had a brand new rebuild kit and it runs way better now with the new ones.
it's bogging...so apparently not.
Just because the oem had a new rebuild kit doesn't make it right.
Most of the rebuild kits are junk too, and if you used the jets or jet needles out of the rebuild kit, that's another problem.
 

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Discussion Starter · #15 ·
the thing is I have tried every thing with the carb even replacing it. now it idles grate without choke it just keeps on bogging it wasn't the cdi I bought a new stator but i am debating replacing it do you think I could be a slightly bent valve that cant be seen unless taken out. here is the video of the problem
Figured out that there is a 3rd clutch safety switch that I did not disable
 
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