1. Hello Guest. You have limited privileges and you can't "SEARCH" the forums. Please "Log In" or "Sign Up" for additional functionality. Click HERE to proceed.

YICS sync

Discussion in 'XJ Technical Chat' started by stevo, Jun 24, 2009.

  1. stevo

    stevo Member

    Messages:
    31
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Mississippi
    I'm sure that this has already been addressed but...If the purpose of the yics tuning tool is to block the ports in the yics passage so that you can sync, why cant you just twist a foot long length of high temp hose into the passage and completely block it off? Wouldn't that perform the necessary function of isolating the vacuum draw on each carb?
     
  2. SLKid

    SLKid Active Member

    Messages:
    1,471
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Troy, Va (Charlottesville)
    Be SOB to get out after It got hot I assume. Rubber expands. The YICS tool has the ability to "push" the rubber out, to block off the Vac. and then has the ability to "shrink" the rubber bits to pull it out
     
  3. RickCoMatic

    RickCoMatic Well-Known Member

    Messages:
    13,843
    Likes Received:
    65
    Trophy Points:
    48
    Location:
    Massachusetts, Billerica
    Yes it will.
    But, there's an appreciable Vacuum at the Port.

    Getting the Hose all the way through it could be tricky.
    But I could see trimming and end and sticking a long piece of Brazing Rod through the Hoose to stretch it. Lube it with Marvel.

    Shove some Patches of Terrycloth saturated in Carb Cleaner all the way through to clean-out the Passage. Takes more than a few!
    Anything you can stuff in there and remove will do the trick.

    I stuffed a narrow strip of T-Shirt soaked with Marvel Mystery Oil (Or vegetable oil) all the way through and then ... stuffed the Passage closed and tuned-er right-on up.
     
  4. stevo

    stevo Member

    Messages:
    31
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Mississippi
    For some reason I was under the impression that the reason the yics tool had individual segments for blocking each port was to leave necessary areas of the passage open to air movement while performing a sync. If it's just a matter of plugging up the whole passage then that shouldn't be too difficult.
     
  5. wontonrunner

    wontonrunner New Member

    Messages:
    23
    Likes Received:
    0
    Trophy Points:
    1
    could a guy use a piece of high temp hose that was just a smidgen smaller than the holes, plug one end and install an air fitting at the other end and use a hand pump to pressurize the hose causing it to expand and close of any and all necissary passages?
     
  6. Carvall

    Carvall Member

    Messages:
    220
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Seattle
  7. RickCoMatic

    RickCoMatic Well-Known Member

    Messages:
    13,843
    Likes Received:
    65
    Trophy Points:
    48
    Location:
    Massachusetts, Billerica
    "could a guy use a piece of high temp hose that was just a smidgen smaller than the holes, plug one end and install an air fitting at the other end and use a hand pump to pressurize the hose causing it to expand and close of any and all necissary passages?"

    <><><><><><>

    Off-hand, I'd say yes.
     
  8. SLKid

    SLKid Active Member

    Messages:
    1,471
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Troy, Va (Charlottesville)
    Thats.. kinda smart actually.
     
  9. stevo

    stevo Member

    Messages:
    31
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Mississippi
    Ok. So I attempted to sync my carbs today. I am following Ricks old school method with one vac. gauge. I first used strips of gym socks soaked in marvel. I stuffed it as tight as it would go. When I began balancing the carbs I noticed that as the #2 was adjusted, the #3 value decreased. Is this normal, or does this indicate that the carbs were not truly isolated in my packing of the yics chamber? I removed the packing and used a cotton clothesline soaked in marvel with identical results.
     
  10. RickCoMatic

    RickCoMatic Well-Known Member

    Messages:
    13,843
    Likes Received:
    65
    Trophy Points:
    48
    Location:
    Massachusetts, Billerica
    Multiple Factors to consider:

    Adjustment of a Throttle Plate CLOSED to Match the Value of another ... will GENERALLY cause the Engine to LOSE RPM's ... reducing the Manifold Vacuum all across the Board.

    You have to MAINTAIN a STEADY RPM ... By Orchestrating what you are doing.
    If you OPEN a Throttle some and the Revs INCREASE ... You have to Back-Off on the Idle Adj Rod ... to bring the RPM's back to the BaseLine you are working at for Sync.

    Try to keep the RPM's down and get a GOOD Sync.
    Once you have them dancing together like the Rockettes ... cheat the Idle UP to just shy of 18-Hundred ... 17-50 ... /75 ... and see if there is any difference.

    If there is ... some say ... Split the difference.
    Others say ... correct for Off-Idle Performance.

    I go with the Off-Idle crowd.
    The Tweaking of the Pilot Mixtures will make it Idle when right.

    (If there was an Air Leak in the YICS Chamber while doing the sync ... the Bike would have raced or hunted)
     
  11. wontonrunner

    wontonrunner New Member

    Messages:
    23
    Likes Received:
    0
    Trophy Points:
    1
    thanks....4 years of engineerings school and a lifetime of farming (my short lifetime anyways) has made me rather creative and somewhat lazy...if i can find a cheaper, simpler method that takes less effort...i usually try. :D
     
  12. Carvall

    Carvall Member

    Messages:
    220
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Seattle
    Hey wonwontonrunner!! Did you see the lonk I send. It is actually more practical.

    Let me know what you think. It worked well on my XJ
     
  13. Dodger62

    Dodger62 Member

    Messages:
    56
    Likes Received:
    1
    Trophy Points:
    6
    Location:
    Renton WA
    Got back to the basics. The easiest way to clean the YICS ports in the bike is using a good solvent and a shotgun cleaning kit. A .30 cal cleaning rods and patched will also work but 12 ga workd better. You can even use the wire brush end if necessary. Second option are bore brushed from your local NAPA store. But these are a bit flimsey and lack the rigidity of the gun cleaning rods and have a tendancy to fall apart.

    Good Luck

    Dodger 62
     

Share This Page