KTM LC8 Air Filter Kits by SW7

Discussion in 'Vendors' started by Sporting Wood, Mar 14, 2013.

  1. ManuC

    ManuC 950 SM

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    Dec 20, 2013
    Oddometer:
    164
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    Ardennes Belgium

    I have almost the same setting and I thing it is lean try 2 or 2.5 on the screws idle
  2. Sporting Wood

    Sporting Wood I

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    Oct 18, 2011
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    897
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    Horneytown, NC
    Probably rich judging by you guys settings. If it coughs and stumbles, surges then that's typically a sign of lean. A hesitant, lazy throttle is a sign of rich. At what rpm are you getting this?

    If its at wot, could also be a sign of a weak fuel pump or partially clogged fuel filter. I mention it as I've seen this already on a couple bikes. Spent some time chasing it and wondering why mains didn't fix it too!

    If you find its lean at the top end, that means a bigger main...
  3. ManuC

    ManuC 950 SM

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    In my case it is not in the top end it is when I close en re)open the thorthle slowly 1/8 open I have a hesitation that is why I think it's the screws fuel
    But I don't know if it's to rich or lean...
  4. Sporting Wood

    Sporting Wood I

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    It could be lots of things. The screws though, treat them as a fine adjustment. I tend tonser them in the middle of their range, 1.5 turns out, and adjust the other parameters. If its rich just above idle and below 4500 rpm then its the most common issue we have setting up these carbs. Its all about float height and the pilot jet size. Some bikes simply cannot take the 45 pilots, or it could be that you may have a tight exhaust valve, or you may not have factory airjets installed, or can timing could be a little off, tensioner weak, etc...


    I would verify float height as they are a pia to get right. If OK, I may would set a little leaner. Pull the plastic top flange and make sure idle air jets are 80 & 50. Clean float valves... Watch it running w/o the filter and look for whisps of back charge coming out of one of the carbs. If that's the case, adjust the valves good then try everything again. If you have more than the usual valve clatter, check out cam chain tensioners.

    If you are encountering rich feeling at 4000 rpm, you may consider dropping the needle to 2 and richen up the floats a little to compensate.

    If you simply cannot get the thing to run on the 45's well, drop back to 42 pilots and beef up the mains a few sizes. You may need to lower the float to compensate some too, passing by the target.

    Hope it helps and good luck.
  5. ManuC

    ManuC 950 SM

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    Dec 20, 2013
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    Thanks SW for your implication and reply
  6. Sporting Wood

    Sporting Wood I

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    Oct 18, 2011
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    Location:
    Horneytown, NC
    All orders shipped so everyone is getting them by Xmas. Cheers:freaky

    Thanks to everyone for being patient while we churned through a rather extensive backorder list. Everything is back on the shelf and ready for immediate shipping. Thanks!
  7. mousitsas

    mousitsas Long timer

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    Oct 10, 2008
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    3,006
    Location:
    Athens, Greece
    SW and ManuC

    I just fitted an AEM wideband gauge. At the point when the hesitation occurs is I think when the needles begin to rise (15-25% throttle) and AFR shoots at well over 17. I am trying to keep throttle as steady as possible and increase very slowly, when ths happens.That is at a high enough gear and incline to keep engine load at max. So it seems the needles need to be raised. Didn't have the chance yet to try WOT for a long enough strech, but it seems that when revs rise above 6000, AFR is somewhere between 12 and 13.
    Needles are the FP at #3, floats 4 - 4.5mm, 170/172 mains, 45 slows all else stock.
    I have set idle with the screws at AFR 13.5 or so which corresponds at 2 turns out.

    Any comments?
  8. Sporting Wood

    Sporting Wood I

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    Oct 18, 2011
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    Good work! You are correct. You will need to raise the needle. You checked your air jets, right? Should be stock 80 & 50. That will also cause a lean spike...

    When you raise the needles, it will typically mean that the main will bleed more, prompting you to lean out the bottom end a bit. Could mean an even taller float, I've never gone over 5mm, or a drop back to 42 pilots.

    Congrats, you have one of the strong LC8's. Most of them won't run /4.
  9. mousitsas

    mousitsas Long timer

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    :freaky:clap:lol3
  10. ManuC

    ManuC 950 SM

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    Thanks Mousitsas :freaky
    I will try 4 on the needles for the rest I have the same jettings only the fuel screws on 2.5 are differents.
    Or first try to put 172/175....
  11. 2kool2be4gotten

    2kool2be4gotten Adventurer

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    Oct 7, 2008
    Oddometer:
    39
    Location:
    Waterloo, ON
    Back ordered Over-Sock Filter received today, just in time for topping the tree :) Thanks for putting all of this together!



  12. mousitsas

    mousitsas Long timer

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    Went for a ride today with the needles @4 stop
    Problem has disappered stop
    Bike is mental stop
    This filter setup should not be legal stop
    Still no chance to open it up for top speed to check mains stop
    Will report at first chance stop

    Merry Xmas to all :clap
  13. ManuC

    ManuC 950 SM

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    Yes :clap:clap

    Just finish to put mine to 4 but with the weather no chance to ride it :becca

    Thanks Mousitsas and Merry Christmas to all
  14. ManuC

    ManuC 950 SM

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    VoilĂ  :clap:clap just make a little test and Bingo no more surge like Mousitsas :freaky

    Now just the fine ajustement with the fuel screws and may be drop the mains to 168/170 or 165/168 (I think it pulls harder before with 165/168)

    For the moment

    Mains 170/172
    Needles FP at 4 from the top
    Floats 4 mm
    Pilots 45
    Fuel screws 2.5
    From 0 to 1000 ft level
  15. mousitsas

    mousitsas Long timer

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    Nice!
    You must be right about the smaller mains. I will try tomorrow to give it run at WOT.
  16. ManuC

    ManuC 950 SM

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    Impatient of the results.

    Thanks
  17. ICERIDER

    ICERIDER Adventure Rider

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    Stanley Falkland Islands
    Nice bedtime reading:nod
  18. renogeorge

    renogeorge Long timer

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    And this filter setup does the same for the 990 FI!!!
  19. mousitsas

    mousitsas Long timer

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    The weather has taken a dive, lots of rain, will have to wait for a couple of days unfortunately, for WOT AFR readings.
  20. ManuC

    ManuC 950 SM

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    Yes the same here .... patient