Yamaha Grizzly ATV Forum banner

grizzly 600 idle adjustment

13990 Views 2 Replies 3 Participants Last post by  dezz
just recently joined this forum earlier today hoping to get some more helpful tips on my grizzly.

a little back story on my situation. i bought a 99 grizzly 600 for $200 guy couldnt get it to run and let it sit for 4 years. I tore the carb apart put a new needle and seat in it and cleaned all the jets and passage ways in the carb with seafoam carb cleaner and air. put the carb back in and it fired right up but idled very high. i adjusted the idle with the screw thats on the cable and got it where it sounded healthy and smooth, went put on a ride and it idled down when i came to a stop and it shut off. turned the idle up some and it ran fine again. the next day when i started it it idled really high again i let it warm up and idle never dropped so i adjusted it back down and it died again on a ride.

my question is, is there a proper procedure to setting the idle like there is on cars. or is it as simple as just trying to find a happy place for it.
  • Like
Reactions: 1
1 - 3 of 3 Posts
Idle is adjusted like a car carby, there are a few things that can cause an idle hang up.
Sticky or frayed inner cable(not lubed)
Outer cable jammed or squished on frame parts or under tank.
Routing of cable not taking easiest route(cable too short)
Improper adjustment of cable free play.
Thumb throttle needing lube.
Worn nipples on end of cable moving when throttle closed.
Butterfly shaft sticking or return spring weak.
Loose screws holding adjuster plate(if it has one)
There's been a couple of threads lately with sticky throttles, check 'em out.
  • Like
Reactions: 1
This is a common issue to happen on the Grizzly 600, especially one's that have sat for long periods of time.

You got to make sure intake adapter boot o-rings are in good shape and sealing well. Sometimes they leak when cold, and this will cause idling issues. Then they seal once everything is up to temperature. Make sure the adapter boot is not torn/cracked as well (boot between carb and cylinder head).
Next, is you got to make 100% sure the pilot circuit is completely clean in the carburetor and the pilot needle is adjusted correctly. Play with your pilot needle some (no more than 1/8 turn adjustments at a time) and see how it changes your idling/engine running.
Last but not least, get rid of the stock air filter. It's too restrictive. No matter what I did to my extremely well maintained 600, it still had erratic idling issues. Once I got rid of the stock air filter and installed a Uni Filter, I never touched the idle adjustment again.
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.