Idles fluctuates?

[turbocamino]

Hello,Out of the blue,hot only, my idle will raise a hundred or so...at times will return (to 950) mostly not though..I pulled the tank to poke around some and blow carb cleaner and air thru the air jet/bleeds in the carb face...the one bleed,on the left, i can get out but the one across from it? is it serviceable?  i cant really poke anything thru it, nor does it look like it comes out?  thanks.

[turbocamino]

  also...any other suggestions appreciated.

[jscgdunn]

May want to start here:

http://www.fjowners.com/index.php?topic=658.0

There is a ton of info in the files section.

Jeff

[turbocamino]

  Thanks..thats a great read.

[movenon]

Check your diaphragms (blow check them if the carbs are off the bike)? Have you checked the plugs to see if any one cylinder is burning differently, to possably isolate the problem. Intake O ring air leak ?
George

[racerrad8]

Check your diaphragms (blow check them if the carbs are off the bike)?
George

Why would the carb diaphragms have anything to do with the idle?

Randy - RPM

[racerrad8]

The jet on the right is a fixed air bleed for the cold enrichment(choke) circuit. It does not have anything to do with the idle speed unless you still have the choke knob pulled.

You will not get anything from that jet unless you charge the small hose from the choke vent or the fuel dip tube in the bowls.

If they are plugged, you need to tear the carbs down and have them cleaned in an ultrasonic cleaner as they as not a removal/serviceable jet.

I do not recommend putting anything through the jet as you cannot compensate if the hole gets enlarged to allow the enrichment circuit to function properly.

950 is too slow on the idle speed, it should be 1050-1100 rpms...

Randy - RPM

[FJ_Hooligan]

According to the linked article in a previous post, the fixed orifice on the right is an air bleed into the needle jet circuit.  
I can confirm this as when I blow carb cleaner into that orifice, it comes out where the needle jet is (that's how I tell that it is clean).

I think this is why the needle jet has 4 sets of holes down its length, they allow air to mix with fuel being drawn up the needle circuit.  This has got to be the passage where fine dirt from a crappy air filter gets through to accumulate on the needle jet.

[movenon]

Check your diaphragms (blow check them if the carbs are off the bike)?
George

Why would the carb diaphragms have anything to do with the idle?

Randy - RPM

Just a brain fart     
George

[turbocamino]

thanks guys, I do suspect that possibly due to the uni-pod type filtration,i have picked up some crud in a passage way. Each spring i do take the carbs apart, as far as i can, and soak,spray and blow them out...maybe this spring i will get the ultra-sonic cleanse as suggested .                         

[RichBaker]

Foam filters don't let much dust thru, from my dirt biking experience, but over-oiling may allow some oil to clog the orifice.

[turbocamino]

I want to share what finally fixed the intermitant,fluctuating idle...after spraying/blowing out as many passages as i could get to,air/fuel,main,pilots,emulsion tubes,air bleeds..what did it was cleaning,lightly,with a scotch-brite pad and carb cleaner, around the throttle blades and bores and lubing the blade shafts/linkage..just got back from a 50 mile jaunt and it didnt happen once...  I wanted to share in the hopes it may help someone,sometime.  Thanks for all the suggestions!

[racerrad8]

..what did it was cleaning,lightly,with a scotch-brite pad and carb cleaner, around the throttle blades and bores and lubing the blade shafts/linkage..

I am concerned about the amount of dirt you are getting through the air filters. I read you were using the UNI pod filters, how are you servicing them and what oil are you using?

The carbs I normally see with UNI foam filters are far cleaner than all other aftermarket filters.

Also, if the base idle is set to the proper idle speed of 1050-1100 any accumulation on the throttle plate will be less due to air flow and not affected if there does become a build up. (which should not happen with the UNI filters)

And finally, when was the last time they were synced? If one is coming closed or close to it, the idle will do all kind of weird things.

Randy - RPM

[turbocamino]

The tip or thought of the idle speed got me thinking about flow around at the blades...which in turn had me focus there....which did the trick(thank you very much)  Concerning idle speed though..at anything over 1000 idle,  i dont like how hard it bangs into gear when i drop it in first...i have been over the mounts for condition and tightness and all appears fine..may just be my personal preference? so i settled on 1000/975.  I forget the brand of individual air filters i have but they look like a basic K&N gauze type filter...i havent oiled them if a long time as i have read oiling can be an issue?.  I do soak them in simple green and blow them out every spring...they do appear very clean when done. I could oil them then blow them dry?    Nevertheless, dirt came from somewhere...Is foam a better choice?   Carbs have never been synched..no doubt, at 19K,it could stand to be done...The bike has always ran flawless,so i let it be.

[ribbert]

..at anything over 1000 idle,  i dont like how hard it bangs into gear when i drop it in first...

A few hundred revs won't make much difference to the banging into first. It is very pronounced on the FJ. The only time I start my bike in neutral is first start of the day, when the clutch is sticky, and can be put in gear without a clunk anyway when it's cold. I always leave it in gear in traffic for safety reasons and I have the habit of parking it in gear and starting it in gear.

Although my reasons for the above routine are not primarily to avoid the clunk, it has that result.

....basic K&N gauze type filter...i havent oiled them if a long time as i have read oiling can be an issue?. 

A foam filter without oil is little more than a rock an pebble barrier. It needs oil to function as an air filter. Yes your bike will run fine with it dry but it's not doing it any good.

...i havent oiled them if a long time as i have read oiling can be an issue?. 

Don't believe everything you read on the net.

Noel