recalibrating my CV on my twin cam 88

Discussion in 'Softail Models' started by snaphap, Jan 26, 2011.

  1. snaphap

    snaphap New Member

    I have a 2000 Heritage Twin Cam 88 with Drag pipes and a Drag Speacialtys Air cleaner. Internally the motor is stock. What main jet and pilot jet should I start out with. I dont like my bikes running lean!
    thx dan
  2. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

    It's hard just to point out a set of jets and it be right for every bike. The drag pipes will make it a little trickier. If I had to just make a guess, Im thinking 46 - 48 pilot and a 190 - 195 main. Shim the needle with two #4 washers, gain access to the adjustment screw and go from there. Lots of info on this site concerning this subject. Check self help and use the search function. It should provide you with enough reading for days.

    Good luck and let us know how it works out,

  3. karlsbike

    karlsbike Active Member

    Bodeen is right - with those drag pipes, it'll be hard to get it running smoothly on mid revs.
    I'd buy a range of mains (185-195) and pilots (45-48) and those washers. In additon, you could try the '88 XL needle.
    Following the CV tuning advise found here, you should be good to go...
  4. Brutal FXDX

    Brutal FXDX Active Member

    I agree with the above. Stock main jet is 190 and i would leave it alone. stock idle jet is 45 you can leave it too or try to find a 46 (harder to get)Think 48 may be too lg.
    Use 2 of the washers under your needle will give some more fuel on the midrange. Adjust idle mixture screw 2.5 to 3.0 turns out with 45 idle jet.

    Anytime im tuning a bike with dragpipes w/o baffles i usually put some eye bolts and two nuts through the holes that used to hold the baffles in. Helps with exhaust wave scavanging. If you dont have small eyebolts ive used reg bolt and spacers.

    BUBBIE Well-Known Member

    Remembering the Old HONDAS that had adjustable(open close) outside, Spring Loaded internal Washers on a bolt head that you could turn IN-OUT to cut the exhaust Flow and NOISE.. LOUD when Opened and obnoxious....

    Lots Of GOOD information given in ALL of the ABOVE posted answers.... Not mentioned tho;
    I would Not buy any kits... Single Jets needed and Less$$ and I do like the mention of the 88 XL sport needle, I have had great running in my dyna using it..

  6. Brutal FXDX

    Brutal FXDX Active Member

    Point taken bubbie. I used to use dyno jet kits when i first started wrenchin, thinking that was the way to get your CV to run right. Ive learned from some of the best and my last mentor (Dennis R. Thurlow of Fayetteville NC)told me to take that junk dyno jet kit out and throw it in the trash. He explained to me that carb companies like keihn have been making carbs long enough and they know what the're doing. All that jazz about drilling slides and lighter springs is really a bunch of nonsense. For 15-20 bucks tops you can make any stock CV run even better than the same carb with a 120.00 dyno junk kit.

    So still to this day a bike comes in with running (carb) issues, and has a dyno jet kit. I ditch the kit and install stock emultion tube and jet and stock springs if ive got one. Cant do much with the hole that was drilled in the slide, but ive never had any issues. Been using up all my stock emultion tubes that ive once taken out in the past
  7. kemo

    kemo R.I.P

    I learnt a long long time ago that keihn, harley ,yamaha, Ford or Gm have way more money then any of the after market suppliers have for R&D.
  8. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

    If you want to run drags, you might consider installing some cones at the heads. As far as tuning, you are gonna have to play with it to get er right. But I agree with the guys above. Forget all that fancy jazz. This is a simple carb, keep it simple! Some info below, but you will have to tweak from there:

    *Twin Cam CV Carb Rejet Suggestions - Harley Davidson Community

  9. Jack Klarich

    Jack Klarich Expert Member

    You could run splitters in the pipes for a bit of back pressure or Lolli pops for the same with out giving up your loud bark, It will make tuning a bit easier and give some needed back pressure:s
  10. karlsbike

    karlsbike Active Member

    I heard of it way back on a sportster list, and really liked it on my then '88 XL. I have it in my Tourer as well, and she is running strong for a mostly stocker. I remember it as being a bit slimmer than the stock needle, giving more fuel and response mid-range.

    Snaphap: Don't know how much you know about tuning those CV's, but I recommend to follow the tuning advise found on this list. The target should be to jet right, not overjet. Very few stockers (at least EVO's) need more fuel where the main jet comes in - at full throttle. Too big main can give you sluggish performance. Off-idle and mid speed is what I would aim for, and that would be the pilot jet and needle.