Harley CV Carb Dice Idle Adjuster

Harley CV Carb Dice Idle Adjuster – 4mm Old-School Idle Speed Screw

Give your CV carb some personality and make idle tweaks stupid-easy. This Harley CV carb dice idle adjuster replaces the boring stock idle speed screw with a custom dice knob you can grab with gloved hands at a stoplight—no tools, no digging behind the air cleaner. It’s the perfect blend of function and attitude for choppers, bobbers, and old-school customs.

CNC-machined hardware and a detailed dice knob turn a basic tuning point into a statement piece. Designed for the idle speed circuit on Harley CV carburetors (not the mixture screw), this 4 mm adjuster lets you fine‑tune idle on Sportsters, Dynas, and other CV-equipped Harleys with a quick twist. Built by riders in the USA, for riders who care how every inch of their bike looks.

Key Features:

• Custom dice idle speed adjuster for Harley CV carburetors.
• 4 mm thread to match factory CV idle speed screw spec.
• Designed for idle speed, not the fuel mixture screw—no confusion, no guessing
• Tool‑free adjustments at lights, gas stops, or in the garage.
• Available in multiple colors to match your tank, grips, or accent parts.
• Designed and built in the USA with garage‑builder mentality.

Style & Color Options:

• Run your idle knob like a tiny dice hanging off the carb throat:
• Classic opaque colors: black, white, red, blue.
• Loud chopper tones: lime green, purple, pink.
• Translucent and marble vibes for that 70s chopper feel.
• Dial in a color that ties in with your paint, grips, or other accents so your carb looks as intentional as the rest of the bike.

Fitment Guide:

• Harley‑Davidson models running CV carburetors (Sportster, Dyna, many Evo‑era Big Twins).
• 4 mm idle speed screw replacement location on the side of the CV carb body.
• Compatible with most aftermarket CV carb setups that retain the stock‑style idle speed screw.
• If you’re unsure your carb is a CV, look for the round, vacuum‑style top and side‑mounted idle screw location—not an S&S or Mikuni flat‑slide style.

FAQ:

1. Q: Is this for idle speed or idle mixture? A. This dice adjuster is for idle speed only—it opens and closes the throttle butterfly to raise or lower RPM. The idle mixture screw controls fuel ratio and is a separate part.
2. Q: Will a 4 mm idle screw fit my Sportster CV carb? A. Yes. Factory Harley CV carbs use a 4 mm thread for the idle speed screw, so this dice adjuster drops in as a direct replacement.
3. Q: Why is my stock idle screw hard to reach? A. On many Harleys, the stock screw hides behind the air cleaner and bracket. This extended dice adjuster sticks out further so you can reach it by hand, even with gloves on.
4. Q: Do I need to trim the idle spring? A. Sometimes. Depending on your carb and bracket setup, you may need to trim the idle spring slightly so the dice knob seats correctly and turns smoothly. It’s a quick, one‑time setup move that gives you perfect feel.
5. Q: Will this work with my custom air cleaner? A. In most cases, yes. As long as your air cleaner doesn’t completely wrap and cover the side of the carb, the dice knob will have room to spin. Low‑profile or minimalist air cleaners usually work best.

Designed in the garage culture of Lake Worth, Florida, this Harley CV carb dice idle adjuster comes from the same mindset as your build: no plastic, no corporate catalog feel—just real parts that make your bike look and work the way you want.