A new noise

[gtosteve65]

Hello everyone,
So over the past 2 days when starting my bike and riding for the first 5-10 minutes there is a new noise that has come up. Its hard to describe but it sounds like a low whining noise. I know its not the fuel pump because I can hear that sucker clear as day. It sounds to me like it almost might be coming from around the air box area, but with no way to tell just yet. Also the noise is constant no matter what the revs. So its not a moving part (most likely). I'll be ripping it apart tomorrow to take a better look. It did just complete a 200 mile ride a week ago and I want to take it to the Laconia Motorcycle rally on Saturday. Any ideas what I might be hearing?
Thanks

 

[TownsendsFJR1300]

Vacuum leak maybe around the air box, split vacuum line hose, etc.

If you can hear it with the tank on, should be pretty easy to find once that's lifted.


And its only when its cold? And I gather the bikes running good otherwise?

 

[gtosteve65]

Yea everything is running great. It had a low idle one night, but it was only that one time about 3 days ago.

 

[TownsendsFJR1300]

Pay close attention to the "sync block" (not the correct word):

That unit raises the idle (and enriches the mix) when cold (coolant lines to the right) and I believe the two larger hose nipples are for air.

 

[TownsendsFJR1300]

Anything Steve?

 

[IanHoots]

Is that a wax stat to allow more air in when cold? I noticed it the other day when I had the tank off. I take it the tubes (lower) of the photo are some kind of pollution equipment?

 

[TownsendsFJR1300]

I know the two lines to the right side are hooked up to the cooling system. When the coolant is COLD it acts with the wax (IDK exactly how it works).

The other two larger air hose nipples, I'm not sure, maybe to the air box?

FinalImpact would know, he's had his apart a bunch of times..

[MENTION=15974]FinalImpact[/MENTION]

 

[gtosteve65]

So I pulled a lot of stuff apart on Friday and couldn't find anything. I saw the piece you guys are talking about but all I did was make sure it was secure. Couldn't find anything wrong, it was getting late and I knew I wanted it back together before the night was over. So the next morning I rode to and from Laconia NH (200 miles from my house) with no problems. When I started it up this morning there was no noise! Very odd, maybe something was a bit loose and I just put it back in place.
If anyone else has a problem like this I suggest taking a bunch of things off around the air box and putting them back on. Seemed to work for me.
Thanks everyone for the advice!

 

[FinalImpact]

Honestly I've never had the idle air controller apart or off my bike.

The large inlets are filtered air from the box. Those 4 chambers have a plate that bolts on, the plate has 4 hoses which then allow air into the throttle bodies below the throttle plates or butterflies.

Hot water acts on a bi-metallic spring (like a thermostat) to move control valve which changes how much idle air the engine gets.

That valve does 3 jobs.
1. sync screws for tuning/balance cyl by cyl.
2. Idle speed contol.
3. Fast idle control during warm up. Air metering only.

It never hurts to look and inspect. Glad you solved it.