Hanging idle = too small pilot?

Discussion in 'EFI/carb' started by Swampds, Dec 31, 2008.

  1. Swampds Husqvarna
    AA Class

    Location:
    Sarasota Florida
    I have a Euro 07 that came with some extra emission stuff. I finally got around to taking off some of the extra garbage in the air filter area. There is a little pump that blows air into the intake. I removed that and routed the crank vent to the top of the airbox with a straight shot from the headcover. I capped the fitting that goes into the intake.

    I noticed it now hangs on the idle when I give it gas. It goes from 2000 rpm to 2700. The idle adjustment is turned as low as I can get it. Do I need a bigger pilot, adjust airscrew, or change my AP Squirt.

    My jetting specs are this:

    DVR 4 from the top.
    Stock main and pilot
    70 leak jet with o ring mod on AP

    TIA
  2. tadgh Husqvarna
    A Class

    is the stock pilot 45? if its ticking over at 2000 that sounds high to me should perhaps be closer to 1500-1600. i wound up with 38 pilot and air screw 1 1/2 turns out to get mine running right.

    pull the choke when its hot and see if it nearly kills the engine then i'd say the pilot is too big
  3. Swampds Husqvarna
    AA Class

    Location:
    Sarasota Florida
    When I pull my choke out it puts the idle at about 3,000 rpm. It seems like I may have a couple of different issues going on.

    More opinions would great.
  4. tadgh Husqvarna
    A Class

    well that now sounds like either pilot too small (unlikely) or air screw set way out too far. choke should richen to the point of killing the engine so if it doesnt the bike is either getting too little fuel at normal or much too much air.

    when you took off the euro stuff did you put a cap on the boot from the back of the engine into the carb? there is a little breather hole there that is open when you take off some of the emisions crap.
  5. Swampds Husqvarna
    AA Class

    Location:
    Sarasota Florida
    I put a cap on intake. I used some good hose with a tight bolt jammed in with some RTV. I don't think it is leaking from there. I noticed there is a sensor that is attached to the kickstarter side of the airbox. What does this sensor do....and should I unplug it?
  6. tadgh Husqvarna
    A Class

    my bike has the race wiring harness in it, so when i stripped out the old harness that sensor came out also as there was nothing to plug it back into on the new harness. so strip it out also, i assume you didnt have these issues until you removed the first stuff?
  7. Swampds Husqvarna
    AA Class

    Location:
    Sarasota Florida
    My idle was always on the high side and also the choke would elevate the idle before all the changes. The main thing I am noticing that is different is the hanging idle that takes 4-5 seconds to come back.

    It would be nice to know some of the proper names to the stuff I am unplugging. I am curious to find out what this sensor does and what it is called.
  8. Dan M Husqvarna
    AA Class

    Location:
    NE Illinois
    Husqvarna Motorcycle:
    07 TE250
    Other Motorcycles:
    11 R1200GS 07 TuonoR 02 V11 LeMans
    Are you sure the idle adjustment all the way down? Can the cable be holding it up? Regardless of jetting, closing off the air by turning down the idle should bring that idle down.
    Often an idle that hangs up is a sign of the carb being between circuits. If the slide is slightly up and fuel is being pulled past the needle it will take a while to settle.

    JMHO
  9. Swampds Husqvarna
    AA Class

    Location:
    Sarasota Florida
    I went from a 50 to a 48 pilot. While taking out the air screw I noticed it was mostly closed, upon reassembly I went with 1 turn out. It seems like it is running better and the idle isn't hanging as high. I can now get my idle down to 2200 rpm but that is with the adjustment as low as I can turn it. Can that cable bind?
  10. Dan M Husqvarna
    AA Class

    Location:
    NE Illinois
    Husqvarna Motorcycle:
    07 TE250
    Other Motorcycles:
    11 R1200GS 07 TuonoR 02 V11 LeMans
    Take the cover off at the cable crank on the side of the carb. Operate your throttle to see how the cable pulls. See if the cable is holding the crank from returning all the way when the idle stop is backed off. If you move it by hand you should be able to feel and hear it bottom when you release it. There should be a slight amount of slack in the cable when it is at rest. It may be as simple as a cable adjustment at the cover or at the twistgrip.
    Hope this is helpful.
  11. rawperformance Husqvarna
    A Class

    Location:
    Kamloops BC
    Husqvarna Motorcycle:
    2008 TC450
    Other Motorcycles:
    2007 TTR125, 2008 TTR110, 2008 PW50
    My old CRF450 did this as well. What it turned out to be was the relationship between the TPS and base idle settings. Once your close with the jetting and the base idle your TPS may need adjustment. I found this over at TT with a search on FCR carbs/Yamaha? Hope this helps

    Happy New Year!
  12. Swampds Husqvarna
    AA Class

    Location:
    Sarasota Florida
    I feel like an idiot. The idle screw is kind of frozen and it took some serious grip to get it past where it was stuck. It may need some anti seize every now and then.

    I think I may stick with the 48 pilot and see how it works for this race this weekend.
  13. HuskyMax Husqvarna
    AA Class

    Location:
    WV


    The piece you removed that had the hoses attached to it is an air solenoid that allows air to enter the intake on deceleration (when the bike usually has excess fuel) the extra air leans out the bike and allows it to pass the E3 emissions. This setup has been used before on everything from dirtbikes to pickup trucks. And the piece under the right side panel is a temperature sensor. You can remove it but you dont have to.

    I installed the JD jet kit and wound up with a 45 main the winter and a 42 in the summer. The 48 sounds a little big but every bike is different.
  14. Swampds Husqvarna
    AA Class

    Location:
    Sarasota Florida
    Thanks Husky max. What exactly does the temp sensor do? Does it control what the air solenoid does?

    I am guessing that you are meaning pilot and not main with your reply. I had a 50 pilot in before so I figured I would step down a little and see how she does.

    What main are you running? I need to rejet for sea level.
  15. Coffee CH Owner

    Location:
    Between homes - in ft Wayne IN
    Husqvarna Motorcycle:
    2006 TE250, 2013 TR650 Terra - sold
    This has been my experience as well, I've rejetted... 6 or so bikes - TE250/450/510 2006/7 non-efi.

    Don't forget to check the float level - while off bike hold the front brake and lean over... 45ish degrees and fuel should start to leak out the overflow tube at the bottom of the carb. I have always 'wondered' if the float level makes a difference in the jetting but I've not done any experiments.
  16. HuskyMax Husqvarna
    AA Class

    Location:
    WV
    Yeah, sorry I have a case of the dumbass. I'm running a 185 main and the red needle in the fourth position down on the needle. The rubber intake on these bikes are known to go bad and separate. That could be a possible air leak.

    The temp sensor plugs into the black box and what it controls or monitors air temp for, is a mystery to me.
  17. tadgh Husqvarna
    A Class

    at least it was easily fixed :thumbsup: