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CV upgrade

Discussion in 'Motorcycle Tech Talk' started by gwilbon, May 4, 2010.

  1. gwilbon

    gwilbon New Member

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    I bought an upgrade kit for my 1999 FXSTC with the EZ just screw. I am getting ready to install the kit. I have noticed that some other forums recommend drilling the vacuum port on the slide out to 1/8". The instructions with my kit does not mention it. Should I or not? Thanks in advance for any help.
  2. hotroadking

    hotroadking Super Moderator Staff Member

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    nope don't touch that slide!
  3. gwilbon

    gwilbon New Member

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    Thanks, wasn't sure.
  4. hotroadking

    hotroadking Super Moderator Staff Member

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    to explain, when you drill the hole (to make the slide move up earlier) and faster, and then put in a lighter spring the slide can flutter, making it run very poor...

    YOu don't want or need that..
  5. gwilbon

    gwilbon New Member

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    Thought something like that may have been the reason. Now I know. Thanks again. Really enjoy reading the forums but this is the first time posting.
  6. chucktx

    chucktx Moderator Staff Member

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    dont be a stranger!!!!!!!!!!!!! welcome!!
  7. hotroadking

    hotroadking Super Moderator Staff Member

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    post away keeps the board going...
  8. HarleysLR

    HarleysLR Active Member

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    and controversy brewing.... :D
  9. gwilbon

    gwilbon New Member

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    How in the heck can you adjust the E-Z just screw without removing the air cleaner?
  10. JohnnyBiker

    JohnnyBiker Well-Known Member

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    I would go to Harleyperformance.com. They do a good job at explaining how to upgrade the CV.
  11. gwilbon

    gwilbon New Member

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    Thats where I bought the upgrade kit. The instructions say to adjust the screw out as needed to accomplish correct idling but you cannot get to the adjusting screw without removing the air cleaner. So the bike cannot be running.
  12. JohnnyBiker

    JohnnyBiker Well-Known Member

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    Taking the air cleaner off is easy.
  13. gwilbon

    gwilbon New Member

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    It is not difficult at all, but when you remove it, there is nothing holding the carb on. Very difficult to adjust the carb without it running. I gues you make an adjustment then reinstall the air cleaner, and keep going through the same routine until you get it right.
  14. ReeseSS

    ReeseSS New Member

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    I get to mine without removing the AC cleaner,(not a stock AC cleaner) I just reach up behind it.
  15. gwilbon

    gwilbon New Member

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    Mine's stock with a K &N filter. The stock back plate is molded plastic and seems it would be right at home on a '57 Cadillac.
  16. hotroadking

    hotroadking Super Moderator Staff Member

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    you are running the stock HD cover and backing plate...

    It would make reaching anything difficult

    It would be best if you upgrade to a SE backing plate, put your K&N on it and then the cover will be open in the back allows more air and with the re-jetting more power..

    That black plastic housing is restrictive and designed to reduce intake noise (therefore reduce power)

    If you filter is a round K&N then it should work with the SE Kit HD sells for EVO V Twins.
  17. gwilbon

    gwilbon New Member

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    Mine is the stock type filter. I guess I will buy me a Ness Big Sucker or something similar.
  18. hotroadking

    hotroadking Super Moderator Staff Member

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    Call my buddy Phil
    has an indy shop in KS, 20% or more off everyday

    California Phil's Concordia, KS (785) 243-9991

    Ness, HD SE, Kuryakyn has a new one that works great I put it on three bikes
    including mine. Makes a big difference..
  19. gwilbon

    gwilbon New Member

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    Thanks alot I'll give him a call.
  20. Lucifer

    Lucifer Well-Known Member

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    Until you change the stock backing plate a K&N stock replacement filter isn't going to increase airflow enough to really need jetting changes.
    BTW...the drill bit included with the CV performance kit is the same size as the slide port, you just run it through to clean it up, I think it's 7/16" . Drilling to 1/8" and using a lighter spring can cause surging like HRK described.

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