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Adjusting idle does not affect rpm level when bike is warm

cos_fz1

cos_fz1

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Hi,

I purchased a 2009 FZ1 a couple of weeks ago. The bike had about 11.5k miles on it when I picked it up and I have only added about 150 miles since getting it, the weather hasn't been warm enough yet. The bike starts up pretty reliably for a cold start and the bike will be at about 1200-1300 rpms after starting. When I start up the bike when the engine is warm I almost always have to give it a little gas. The problem I am having is that after the engine is warm the idle will drop to around 700-800 rpms. I have let the engine warm up to 185F and then tried to adjust the idle but the rpm level just stays the same. I initially turned the idle screw clockwise based on other reading I had done. I have tried turning it up to 5 complete turns and it makes no difference. I tried to turn the idle screw adjustment counter clockwise and it still makes no difference. The bike does have an after market Mivv Suono exhaust, the EXUP cables are still in place, they were just removed from the OEM exhaust. I have not tried to sync the throttle bodies (haven't ever done that) but it seems that there is a problem with the idle adjustment screw since it has no effect regardless of the direction the screw is turned. The following maintenance was done by the previous owner about 150 miles before the bike was sold:

Oil change (11364)
Front and Rear Brake Fluid (11320)
Air Filter (11364)
Spark Plugs (11364)
Coolant (11364)

Any ideas of what you would do next?

Thanks
Peter
 
Last edited:
FYI, the title should be:
Adjusting idle does not affect rpm level when bike is warm

I was able to edit the title once in the thread but the edit does not show up from the "Home Page"
 
I believe from my reading it may be your thermowax unit... I don't have any first hand experience but apparently it can either be cleaned or modded.
 
Thanks for the response. From the reading I have been doing, the thermowax unit controls the idle when the engine is cold, so I don't think that is the problem.
 
cos_fz1 said:
Thanks for the response. From the reading I have been doing, the thermowax unit controls the idle when the engine is cold, so I don't think that is the problem.
Click to expand...

Negative ghost rider it also opens the throttle bodies when the engine is hot. Similar to a hot start on a dirt bike.

Check out FZ1OA. Member blindspot has a write up on the thermowax unit there.
 
I would first check the idle screw linkage (the long tube like thing that goes from adjustment screw to idle screw) to see if it still connected. Also check to make sure the idle screw did not unscrew out of the throttle body. This has been known to happen when people try to adjust it too much.
 
Kpd1031 said:
I would first check the idle screw linkage (the long tube like thing that goes from adjustment screw to idle screw) to see if it still connected. Also check to make sure the idle screw did not unscrew out of the throttle body. This has been known to happen when people try to adjust it too much.
Click to expand...

I think I am going to check this first. I have looked but have not been able to find a "how to" for this. Does anyone know of one?
 
Idle Speed

My 06 idled about 1100 rpm when I got it but I set it down to about 750/800 rpm. Don't need all that activity when I'm stopped and the throttle response from idle is excellent.

Looks like you got it done already.
 
ReconViper1 said:
My 06 idled about 1100 rpm when I got it but I set it down to about 750/800 rpm. Don't need all that activity when I'm stopped and the throttle response from idle is excellent.

Looks like you got it done already.
Click to expand...

According to the FZ1 Service Manual, page 2-6:

Engine Idling Speed 1100-1300 r/min

---------------
According to the same Service Manual, page 7-6, it looks like to get to the Idle adjust screw wire, you need to lift the tank.
 
So last weekend I lifted the tank and took off the airbox and I could see what I thought was the tube that the idle screw is connected to. I don't have much engine maintenance experience and I could not determine how much more stuff would have to have come off to be able to get to it so I put it back together. I will need to take it in I think to have it fixed, I was hoping I could have gotten to it. I had not taken the tank off before. I was amazed at how much technology they get into such a small place. When I take it in, I may ask if I can watch as they work on it, so I can see what they do. The dealer may say no, but it can't hurt to ask.
 
cos_fz1 said:
According to the FZ1 Service Manual, page 2-6:

Engine Idling Speed 1100-1300 r/min

---------------
According to the same Service Manual, page 7-6, it looks like to get to the Idle adjust screw wire, you need to lift the tank.
Click to expand...

So why do I want my engine spinning over at 1300 RPM when I'm sitting still? I know how to ride and don't stall the bike coming off a traffic light but maybe newbies need the extra RPM to keep from looking like newbies.
 
ballmead said:
I'm surprised the bike doesn't stall out. It would also make the transition from closed to open throttle worse too.

Sent from my Nexus 5
Click to expand...

I just started riding in 1970 and have about mastered moving out from a stop. It's not as hard as racing desert and dodging sagebrush at 90 MPH or riding across Snoqualmie Pass in a snowstorm. I'm working up to making a WOT pass through King's Cross at 2AM with a $50 bill in my off hand.
 
ReconViper1 said:
So why do I want my engine spinning over at 1300 RPM when I'm sitting still? I know how to ride and don't stall the bike coming off a traffic light but maybe newbies need the extra RPM to keep from looking like newbies.
Click to expand...
I`ve always believed and have also been told from mechanic`s that a slow idle is hard on the bottom end of a motor`s bigend bearings etc, especially so when cold, it`s best to have the motor spinning smoothly and oil pump working properly [pumping plenty of oil]
 
ReconViper1 said:
I just started riding in 1970 and have about mastered moving out from a stop. It's not as hard as racing desert and dodging sagebrush at 90 MPH or riding across Snoqualmie Pass in a snowstorm. I'm working up to making a WOT pass through King's Cross at 2AM with a $50 bill in my off hand.
Click to expand...

Ok. I'm not sure what all that means. I guess you're trying to tell us you know what you're talking about and know how to ride. Then I guess you don't need the good people of this forum to give you advice. So, good luck. We will be here
when you need us, which I think will probably be soon.
 
ReconViper1 said:
So why do I want my engine spinning over at 1300 RPM when I'm sitting still? I know how to ride and don't stall the bike coming off a traffic light but maybe newbies need the extra RPM to keep from looking like newbies.
Click to expand...


Oil pressure and oil supply to the bearings , cams and so on will be better @ 1100-1300 rpm. Yamaha has the idle spec in the manual for a reason.

As already mentioned transition from close to open throttle will also be much smoother. Smooth is good in the twisty stuff.


Good oil supply/pressure to the transmission while coasting is also a good thing. I'd suspect the water-pump is also more efficient at the correct idle rpm.
 
Kpd1031 said:
Ok. I'm not sure what all that means. I guess you're trying to tell us you know what you're talking about and know how to ride. Then I guess you don't need the good people of this forum to give you advice. So, good luck. We will be here
when you need us, which I think will probably be soon.
Click to expand...

I needed a good laugh , thank you :rofl::rofl::rofl::rofl::rofl:
 
ReconViper1 said:
I just started riding in 1970 and have about mastered moving out from a stop. It's not as hard as racing desert and dodging sagebrush at 90 MPH or riding across Snoqualmie Pass in a snowstorm. I'm working up to making a WOT pass through King's Cross at 2AM with a $50 bill in my off hand.
Click to expand...

If you already know it all and can ride with Rossi why are you on the forum? Most of us are here to learn, and help others out.
 
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