84 flhtc carb trouble... I guess

Discussion in 'Engine, Fuel and Exhaust' started by Speed Racer, Jul 7, 2010.

  1. Speed Racer

    Speed Racer New Member

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    Hi, Having issues with my 84 evo. very slow free reving but if you get it up to about 2000 and crack it it's not bad. Just the transition off idle is messed up. I can see a shot come out of the accelerator pump, I sprayed through all the passages in the carb, jets are all clear, bowl vent clear, fuel supply to carb is good. The problem is worse with the air cleaner on "and yes it's clean". The idle mixture screw is sealed from the factory and was wondering if that passage might have junk in it. The bike did sit for a couple years but the gas was all flushed out and is now fresh gas. Take it apart again and soak the body in cleaner or what??? Any suggestions are appreciated.
    Thanks,
    Steve
     
  2. glider

    glider Veteran Member

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  3. glider

    glider Veteran Member

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    Oh boy!!!! Hob is at it again :D
     
  4. Speed Racer

    Speed Racer New Member

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    Thanks for the VOES suggestion. It wasn't a problem but while I was testing it I found a loose bolt that holds the rubber boot onto the head. It is much better than it was but still has a flat spot. I'm not sure what carb it is, I'm not that familiar with them. It has a logo on the side that kinda looks like the letter K.
    Thanks Again,
    Steve
     
  5. Breeze3at

    Breeze3at Well-Known Member

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    Steve; Your "K" carb is a Keihn, probably a butterfly type, but could have been changed to the later ('89 ? up) Keihn CV. If it has a black (or chrome) dome with 4 screws as the top, it's a CV.
    The sealed idle screw cover can be removed by CAREFULLY drilling a small hole, then putting a sheet metal screw in the hole and popping the cover out. There won't be any junk in there, but it will enable you to adjust the idle mix.
     
  6. NEWHD74FAN

    NEWHD74FAN Experienced Member Retired Moderators

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    As Breeze says, but start off with gently seating the mixture screw and back out 1 1/2 turns to start. Check if your carb has accelerator pump diaphram near the float bowl towards front of bike, pull the air cleaner off and see if you get a strong spray of fuel down the throat and check for cleanliness. If a lot of black or smell of old varnish, you will need to try Gumout Carb spray to try and clean it while running (wear eye protection and be careful with running bike and spraying it in there). If it improves the off idle performance, you might be in need of more through disassemby, cleaning and blowing out passages (rebuilt kit is about $35).

    Please look in the Self Help section to see exploded diagrams and recommended draining procedure of the float bowl drain plug for particles of rust, also check fuel strainer/petcock/vacuum diapram obstruction and fuel tank lining and such as a precaution based on the age of the bike and when service was last done.