Announcement

Collapse
No announcement yet.

bike jumps around on rpm

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    bike jumps around on rpm

    so, bike is running, sounds very nice and very clean and im happy to be riding, but have an issue still...everytime i start my bike up i have to adjust my throttle cable to get it at the right idle, and when i do its usually fine just sitting there idling, may climb up the revs a little bit but nothing crazy. now when im riding or when i pull in the clutch its a different story, when riding if the throttle cable is im assuming too tight, itll ride at 2000 rpm in any gear with no throttle given to it by me, also if i pull in the clutch it will rise to 4000 rpm.

    okay now say i start it up and i put its idle a little lower than spec, like right under 1000 or right on it, riding is fine and the bike doesnt have "cruise control" anymore, now when i pull in the clutch after its warm and i was riding for a bit, the revs will drop to about 6-700 rpm and ill have to blip the throttle to keep it on, like its a harley or something.

    with this info im guessing the problem should be my throttle cable and it is
    1)improperly adjusted
    2)guided through the bike wrong

    that being said how do i reset my cable to where its fully loose and ready to be fitted on, and whats the best way to guide it through the bike?

    if anyone thinks my issue could be something else, please say so, i dont know how vacuum leaks work so im not sure if it climbing to 4000 rpm with the clutch pulled in is that.
    Ian

    1982 GS650GLZ
    1982 XS650

    #2
    TBP,

    Are you saying that you adjust the idle when engine fairly cool, and then the idel it too high when engine is warm.
    And you adjust the idle when engine is warm, and then it is way too low when engine is not warm .... ?
    If so, that is the lean condition that results from air leak into intake boots, or thier oring, or the orings on the carb choke mechanism. ... or all of theme.
    http://webpages.charter.net/ddvrnr/GS850_1100_Emblems.jpg
    Had 850G for 14 years. Now have GK since 2005.
    GK at IndyMotoGP Suzuki Display... ... GK on GSResources Page ... ... Euro Trash Ego Machine .. ..3 mo'cykls.... update 2 mocykl


    https://imgur.com/YTMtgq4

    Comment


      #3
      Originally posted by Redman View Post
      TBP,

      Are you saying that you adjust the idle when engine fairly cool, and then the idel it too high when engine is warm.
      And you adjust the idle when engine is warm, and then it is way too low when engine is not warm .... ?
      If so, that is the lean condition that results from air leak into intake boots, or thier oring, or the orings on the carb choke mechanism. ... or all of theme.
      my bad no, when i go to turn on the bike, ill have to usually tighten my cable to have it sit and idle by itself, if not itll be too loose and the bike wont be able to idle by itself. (it doesnt self loosen, that is because i loosen it when it does the idle jump with the clutch pulled in, i know, this isnt the clearest explaining of whats going on)

      if my cable is too tight im assuming, the bike will drive itself at 2000rpm with me not giving any throttle at all, and also when i pull the clutch in to shift the rpm will go to 4000 while clutch is pulled in.

      if my cable is too loose (again assuming) i wont have the issue of my revs climbing to 4000 when the clutch is pulled in, but i will have to blip the throttle because if not the idle will go to about 600rpm and then shut off, this is with the clutch pulled in by the way

      im not constantly adjusting the cable while riding, its more so i adjust it before i ride to sit at the correct rpm, and see what happens from there. if i have it at about 1000 when i turn it on, eventually when its all warm im guessing its idle drops down to 700ish or below, but if i have it set at 1100 or a bit higher(within spec) i dont even get to see what it would sit at idling because the thing rises up to 4000 rpm when clutch is pulled in.

      none of this weird idle bouncing stuff happens while im in gear riding, smooth sailing there.
      Last edited by timebombprod; 05-17-2020, 07:16 PM.
      Ian

      1982 GS650GLZ
      1982 XS650

      Comment


        #4
        that being said how do i reset my cable to where its fully loose and ready to be fitted on, and whats the best way to guide it through the bike?
        I tried to help someone else with this recently..https://www.thegsresources.com/_foru...02#post2603402

        ROUTING the cable is found in some of the shop manuals but main thing is, turning the handlebars has no effect..pull-tie it to the frame so it stays right and also be careful turning the handlebars doesn't chafe the cable on the tank or the frame.

        Comment


          #5
          If the throttle cable is adjusted properly, it should never affect the idling rpm. there should always be slack in throttle cable until you turn the throttle. When eng. is cold (not warmed up) the choke cable controls the rpm. When eng. is warmed up, the idle adjuster controls it.
          1983 GS1100E, 1983 CB1100F, 1991 GSX1100G, 1996 Kaw. ZL600 Eliminator, 1999 Bandit 1200S, 2005 Bandit 1200S, 2000 Kaw. ZRX 1100

          Comment


            #6
            update, when starting bike youll hear no pops if you just press starter but if you give it throttle itll start right up, still having to mess with idle but it may be a vacuum leak just gonna search for it, when i rev it'll stay up higher for a bit but will climb down slowly, maybe too much fuel? also took breather hose off airbox side and started it and saw plenty of gas flowing out airbox, reconnected and it stopped spewing out gas, should i have that happening?

            rides good though, just really need to work on forks before i start assuming how well other things work.
            Ian

            1982 GS650GLZ
            1982 XS650

            Comment

            Working...
            X