New throttle cables...NOW 3500 RPM IDLE

Discussion in 'Airheads' started by patrkbukly, Apr 16, 2013.

  1. patrkbukly

    patrkbukly 52 Weeks of warm

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    Alrighty everybody,
    so I replaced the throttle cables....R100 GSPD, 1993. All was simple smooth and easy. Now when I start her up I idle between 3500 and 4,000. Cool at traffic lights but tough on engine temperature here in Miami.

    So there is obviously someplace where there should be slack but there is not.

    DETAILS;
    I did screw down all the way the adjustments on the cable ends on the Bings.

    I did line up the line on the gear wheel and throttle wheel at the handlebar mechanism.

    I did be sure both cable ends went end correctly at the top piece that is attached to the small chain.

    I did remove the brake fluid resevoir on the front brake master cylinder so that I could set the small chain perfectly on the guide-track of the chain and then reinstall the reservoir.

    Idle adjustment screws are left as they were and there is about a 2 MM gap between them and the lever so obviously some slack missing somewhere.

    I also took each package and confirmed cable part numbers for the bike as well as matched them side by side before install. Mine are Bing 32's by the way.


    What the hell am I missing?
    #1
  2. Married Man

    Married Man Been here awhile

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    I did the same job on my 89 GS today. The throttle end is a pita. My guess is that the barrel on the carb end of the cable on one side is not seated correctly or the cable isn't centered in the slot thus holding up the arm on one side or both. Do you see cable flex on both carbs before the arms begin to move?
    #2
  3. Kai Ju

    Kai Ju Long timer

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    A couple of things to check.

    Can you lift the cable out of the adjuster ?
    You should have at least 1-2 mm play on either side.
    If there is no play then the idle screw position is a moot point.
    Make sure you check lock to lock as well.

    Before you check anything else go full throttle on the throttle to make sure that the cable ends are seated on both ends. maybe the cable is hung up in the rubber boot that seals it at the top.

    Also, this is a two into one cable. And the connector block is directional where the cables to the bings are recessed in the block. You can get it one eighty out which will effectively shorten the inner cable.
    #3
  4. AntonLargiader

    AntonLargiader Long timer

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    Could you confirm to us that you used the 090 and 091 cables and that they have 72mm exposed braid per this page? http://largiader.com/articles/cables/

    It sounds like you did everything right, so something you did is not as right as you describe it. I suspect the problem is at the twistgrip; the cable holder lug on the end of the chain should be all the way out against the wall of the housing. IOW it should not be pulled in at all.
    #4
  5. patrkbukly

    patrkbukly 52 Weeks of warm

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    #5
  6. Kai Ju

    Kai Ju Long timer

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    Anton, great resource, thanks for doing that. Not to mention the rest of your website.
    #6
  7. patrkbukly

    patrkbukly 52 Weeks of warm

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    That is a great site...Right On !!
    #7
  8. Kai Ju

    Kai Ju Long timer

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    Did you have a chance to recheck the junction block ?
    Or make sure that you have freeplay in the cable ?
    #8
  9. patrkbukly

    patrkbukly 52 Weeks of warm

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    On Junction box....you mean the metal block attached to the chain where both cables slide in correct?
    #9
  10. Kai Ju

    Kai Ju Long timer

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    No, where the single upper cable turns into two lower cables to the carbs. The slider block inside the housing holds the upper cable, throttle side, in the middle hole and the lower cables, carb side, in the outside holes. The nipples fit into a recess to prevent them from getting wedged against the housing. If the nipples sit on top of the slider block then it's upside down, which could account for 'short cables.
    All of that is moot though if you actually have freeplay at the adjuster on the carb, i.e. you can lift the outer cable up a millimeter or so before you pull the throttle cable itself.
    #10
  11. Mugwest

    Mugwest .

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    If Patrick's PD is stock, it has a twin-pull/twin cable throttle-- no 1-into-2 splitter/junction box throttle as on R80G/S.
    #11
  12. patrkbukly

    patrkbukly 52 Weeks of warm

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    No I don't have a junction box on a 93....I have this...
    [​IMG]

    Borrowed from Infras upgrade thread.
    #12
  13. Kai Ju

    Kai Ju Long timer

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    well never mind then. I got choke and throttle cables mixed up, sorry.

    But do you have freeplay at the adjuster ?
    #13
  14. patrkbukly

    patrkbukly 52 Weeks of warm

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    No problem Kai....and no free play.

    When I get off work I am tearing it apart again and I will see if there is space at the small metal block where the 2 ends go in versus the place where the cables butt up against that little sleeve Pictured above) and see if that cures it....if not....I am putting my old cables back on and pretending this never happened.

    I guess on the bright side....I could just look at this as cruise control and get on with a cross country trip.
    #14
  15. batoutoflahonda

    batoutoflahonda Long timer

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    Whoa there. Don't trip yet. Sounds like you got the right parts. Simple check, open the throttle wide open (bike off, duh), let go and watch both carbs and make sure they hit the stops at the same time. Sounds like either they just got miss routed when you put it back together (like caught between the tank or something)and something is pulling on one or both. Also check to see if the ends are seated in that Y junction. They can pull out in the boots and hang on the edge of the splitter..

    Been there, done this.
    #15
  16. Kai Ju

    Kai Ju Long timer

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    no Y junction, already suggested that only to be educated.......
    #16
  17. batoutoflahonda

    batoutoflahonda Long timer

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    Item 17. School's out.


    Max's BMW + steering


    #17
  18. AntonLargiader

    AntonLargiader Long timer

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    Huh? School on what, how to post images? :)
    #18
  19. patrkbukly

    patrkbukly 52 Weeks of warm

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    You ready.....
    G _ d D #*mn Mother F#*"> son of a biscuit.

    Went over each component from beginning to end with no results. Pulled the cables off one at a time and laid them against the originals.....

    ......the cables are about 1.5 cm shorter than the stock ones...each one....so I assume they were mislabeled, mispacked or who knows what but damn that was a lot of dickin around for nada.

    S&M Motors on Ebay.

    I can't believe it.
    And the whole job started because I was trying to correct a stutter or cough when I begin to accelerate. The bike runs great at speeds its just the takeoff has a stutter almost as if the carbs are out of sync. So I am back where I started, original cables, same issue but....I am idling at 950 now.

    Thanks for everyones replies, answers, support and just overall usual community feel.

    :eek1
    #19
  20. Kai Ju

    Kai Ju Long timer

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    Shool's back in session.

    look at items 12, 18 and 19, which connect to 17, in the same frame, clearly identified as the Choke Cables :D
    #20