2006 Yamaha Kodiak 450 4X4 Erratic Idle

[Errol Bartholomew]

Started my 2006 Yamaha Kodiak 450 up recently (March 2019) and it didn't seem to idle good; the idle was erratic.  I turned off the fuel and the engine eventually speeded up to where the Revere red light started flashing before it ran out of fuel.  I changed the spark plug and no change.  Bought a new carb and installed and still not change.  Starts good and runs great when driving but the idle sometimes doesn't come down to where I can shift and other times it goes so slow that it stops running.  I have stabilizer in the fuel and have started several time in  the winter to keep the battery charge without problem but now that has changed.  I have 5700 miles on it but have maintained it good and it has been kept in the garage since I bought it new.  I have really loved this atv.

Any ideas on what the problem could be?

I'm about ready to take it to the dealer for troubleshooting but at a $110/hour I'm trying to solve the problem myself.

Thanks for any help or experiences any of you have.

Errol

[Ajmboy]

Any change if you adjust the choke? Is the throttle in good operation and not sticking?

[JacobSlabach]

I would check the choke and see if the throttle is sticking..  then maybe is your bike running rich? (you said it sped up when gas supply was cut)

[Frank Angerano]

Why would you change the carb and not just clean it and reinstall ? The carb you put on was it a factory carburetor or aftermarket? 

If the existing carburetor was just dirty due to crud buildup I would clean it up really well blow all orafices out and re install it.  

Set the air fuel screw and the idle to the proper setting and go from there.   

 

[JacobSlabach]

is it a slide throttle carb or a butterfly throttle carb?  I hate the slide throttle carbs- every one I've worked on has issues with idling...

[Errol Bartholomew]

I do appreciate all of the comments.  I finally had the intake and exhaust valve adjustments tested and the intake valve was was way out of tolerance and after that was corrected and a little tweaking of the carburetor the ATV runs super now.  The technician told me that the intake valve (which had never been adjusted - 5270 miles) was the primary problem.

Thanks again to all.

[JacobSlabach]

awesome.  glad you figured it out!

[Frank Angerano]

That’s great.  

Nice work.  

Ride safe ! 

[flyinbrian365]

Awesome glad to hear you were able to get it going good!!