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got an 03 flhtc coming in next week and wondering how people are setting up the cv carb. generally run mikunis which I'm very familiar with but leaving the cv on for a while.I haven't really messed with cv's as I usually pull them off immediately and replace with the mik. doing stage 1 with white bros e slipons. should I drill the slide or not? I am putting a sportster needle in. does the sportster needle need to be shimmed? should I leave the spring as is or cut some links out? appreciate any input.
 

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No, don't drill it. Not sure about the needle in the 03's, but the 02 needles worked very well just shimmed up about .040" with two Keihin needle washers (from Kawasaki) or simple hardware store #4 aluminum washers. No need to change the jets either.
Stock spring is fine, but you could use the one off the 44CV which is about 5 bucks.

If you insist on the sportster needle do NOT shim it, and it is likely you may have to go down on the main jet
 

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I would replace the 03 needle as they are very lean, with an 01 or 02 needle which doesn't make any difference as they are the same part # (27406-00) and shim .040 as Hippo stated. I usually run a 46 or 48 slow jet and the stock 190 main with good results. I do not like the sportster needle as I feel they run to lean by themselves in the midrange.
 

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I've installed the sportster needle in 5 or 6 TC88 FLT bikes (all years except 03) and have had good luck with this setup. The purpose of the needle is to richen the transition range from low speed jet to needle and on into mid range. I've not noticed any lean conditions with the needle or rich condition on the main jet either although I've only road tested and didn't do any dyno runs.

Don't forget about pulling the plug on the mixture screw and adjusting it.
 

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Ed, I have an 01 & an 03 with both experiencing lean in the midrange, I tried the sporster needle with a slight improvement over stock but have had the best results with the Keihen #5 MAHR needle. This needle is the best that I have found for the Twin Cams.
 

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BHBandit:

Interesting. Did you do dyno runs to establish you were lean in the midrange or based on something else?? What kind of exhaust system are you running?? What model bikes are your 01 & 03??

Is the MAHR needle off of a HD CV carb or a carb made for another brand?
 

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Sorry it this seem like a stupid question, but how do you shim a carb. needle and what does shim mean? Thanks. J.T.
P.S. Sorry for jumpin' on the thread.
 

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When you take off the top of the CV there is a diafram with the slide attached & the needle sits at the bottom of the slide The needle slides up & down the main jet to metter fuel by the slide moving up from the amount of air entrering the engine. Shim it up and it lets more fuel in for the same amount of air forcing the slide up.
 
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