Fast Idle Doesn't work on 2nd Gen

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Barrelcactus

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I have a 2007. The Fast Idle on cold start doesn't work. When you start cold just runs at normal idle. So need to hold the idle up with the twist grip so it doesn't stall, till it warms up. I found the adjusting screw for fast idle (reach under tank with long screw driver from right side), but turning it has no effect. I can see the slide for the fast idle next to the left throttle body (looking under tank from left side), but pushing it back and forth has no effect. It won't move far. Hits hard stops both ways. Guess I could take it to the Yamaha dealer. But they charge top dollar ($110 to diagnose), their mechanics are not factory training.

 
My guess based on your brief description of the issue is that (one or more of) the 4 fast idle pistons in the throttle bodies (that move to open up the fast idle air bypass) are somehow stuck in the closed position such that the wax motor (or your fingers) is unable to move them to the open position. With the engine warmed up you should be able to push the fast idle mechanism and see the pistons open and close a little (will be hard to close them against the cold wax motor).

Also, be aware that on 2nd gens the fast idle is adjusted so that the high idle is not that much higher than warm idle, as contrasted to 1st gens where the high idle is ~2500 rpms.

 
Fast idle on the Gen2's is 1500 to 1600 if I recall. Onced warmed up it should drop to around 1100.

Dave

 
My guess based on your brief description of the issue is that (one or more of) the 4 fast idle pistons in the throttle bodies (that move to open up the fast idle air bypass) are somehow stuck in the closed position such that the wax motor (or your fingers) is unable to move them to the open position. With the engine warmed up you should be able to push the fast idle mechanism and see the pistons open and close a little (will be hard to close them against the cold wax motor).
Also, be aware that on 2nd gens the fast idle is adjusted so that the high idle is not that much higher than warm idle, as contrasted to 1st gens where the high idle is ~2500 rpms.
This makes sense. I wonder how I fix this? I had the tank off; but still can't get to these fast idle mechanism, since it's under the throttle bodies and things are packed in tightly. Looks like I could take off the air cleaner and maybe get access. But not sure what I would do to free it. I'm reluctant to push hard on the mechanism from the left side to force.

 
May be take the air box out ???

I tried using one of those cheap USB inspection cameras under there, hopeless.

I know you can remove a return spring but that wouldn't stop that slider mech, that operates the idle valves, from being moved manually.

How long have you owned the bike for ?, a previous owner may have disabled the system.

I've worked on 2 FJR's where previous owners have mucked around with the cold / fast idle system.

 
Not sure if directly related....... Another thing to consider is if you have done a TBS, and the air screws are too far in, you may have some difficulty adjusting the idle... I would redo a TBS but first take all the screws out, clean as necessary, and turn them all gently in until they are seated. Then back them out 1 full turn, redo TBS and set idle to 1100. Then check if fast idle kicks in when cold...... might prevent a deep dive into other things?

 
Thanks for the help! It's time consuming to figure something like this out. I would like to take it to the dealer. But the Yamaha dealers here in Tucson were all bought out when Ridenow moved in. When they moved in all the Yamaha, Suzuki, dealers closed and most of the Kawasaki and one of the Honda shops. They are a huge big box auto-dealership type place with young inexperienced service people. High turnover. Nobody I know trusts them with there bike. They can't even look up the recalls properly. Charge a high price to look at the bike. Not factory trained. Will have to find a shop in another town.

 
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