Replacing the carburetor on a Harley-Davidson Shovelhead motorcycle with a Mikuni carburetor is no different than doing the same with other motorcycle carburetors. The process involves removing the old unit, installing new gaskets on the intake mating face, and bolting on the new Mikuni carburetor. No special tools are necessary; the Mikuni carburetor will install with basic garage wrenches and screwdrivers. Depending on the model, the throttle- response time may improve on the motorcycle.
Instructions
- 1
Use crescent wrenches to remove the old carburetor by loosening the bolts that attach it to the intake manifold. Free the unit. Use another crescent wrench to loosen and free the fuel line spigot. Remove the spigot from the fuel line using a screwdriver to loosen the old line clamp.
2Use a small crescent wrench or screwdriver to loosen the carburetor top. Pull out the throttle slide and disconnect the throttle cable from the old carburetor. Place it aside.
3Unpack your new Mikuni carburetor. Attach the drain tubes to the unit. Use a screwdriver or crescent wrench to open the top of the carburetor. Connect the throttle cable on the motorcycle to the throttle slide after you pull it out. Connect both lines if your motorcycle utilizes two throttle cables. Place the connect slide assembly back into the carburetor. Tighten the lid bolts just opened.
4Push the new air filter onto the air cavity of the Mikuni carburetor. Twist it a bit to make sure the filter is seated in place. Place the filter clamp around the filter neck and tighten it with a screwdriver.
5Swing the unit into place so that the exit of the carburetor faces the engine intake valve. Apply a new gasket to the face of the intake valve. Mate the surface of the carburetor to the valve. Slide the bolts into place to secure the unit to the valve. Twist on a new washer and nuts and tighten them. Use a screwdriver to tighten the exit clamp on the carburetor if it uses a slide-on design instead, slipping over the intake valve diameter.
6Insert the Mikuni throttle spigot into the fuel line of the motorcycle. Tighten it in place with a new fuel line clamp using a screwdriver. Mate the spigot end to the carburetor where the fuel enters the carburetor. Insert the securing bolt through the spigot and tighten it with a crescent wrench to the carburetor.
7Turn the fuel flow on from the gas tank and pull the choke. Start the motorcycle engine. Test the carburetor via the motorcycle throttle. Take the motorcycle for a test ride if the Mikuni carburetor responds correctly.
