Tuning your Harley Davidson carburetor is simpler than most think and can beperformed with a few common tools. This simple procedure is a great Harley tech tipthat applies to all Harley carbs from 1989 to present that use the CV style Harley Davidson carburetor . Earlier models equipped with the older butterfly style carbs (pre-89 Evo’s, Shovelheads, Pans, and Ironheads) are excellent candidates forupgrading to a modern Harley carburetor . Read more about how to upgrade your Harley carb Note: Before proceeding to rejet your carburetor it is recommended that you performthe following tuning procedure. Once the the mixture has been properly tuned thereis often no need to rejet the carb.
modelPreparing the carburetor for tuning will require removal from your Harley-Davidson’s engine but this is easily accomplished. Begin by shutting off thepetcock fuel valve and starting the engine to allow all fuel within the carburetorbowl to be emptied. Remove the aircleaner assembly including the backing platewhich is attached to each head with a banjo bolt. This is a good time to inspectthese bolts for obstructions in their passages. Remove the choke cable from it’smounting bracket on the opposite side of the bike.
The choke cable will stay attached to the carburetor during this procedure.Disconnect the fuel line from the fuel inlet on the carburetor or the opposite endconnected to the fuel petcock, whichever is simpler to access. The hose is likelyfastened using a special crimped clamp. This may be cut or pried off to remove sinceyou won’t be using it again. Be sure to have a new hose clamp available.Next loosen both throttle cables from their adjusters located just beyond where theyexit the throttle grip. A couple turns is usually all it takes to give you enough slack. Ifyou count how many turns each adjuster is loosened then you can return them tothe exact adjustment when reinstalling your carb. This is a good time to label eachcable to avoid any confusion when reconnecting them to the carb’s throttle cam. Asimple “Top” and “Bottom” should suffice when tagging each cable. Now that you have enough slack in the cables you can pull the carburetor away fromthe manifold. A Harley carb is only held to the manifold with a slip fit rubber boot.Gently rock or twist the carb back and forth as you pull it away from the engine.Remove the cables that you tagged and remove any vacuum hoses. If your modelPreparing has multiple vacuum hoses it would be a good idea to label these as well.
Download Carburetor Performance Tuning Harley Davidson Owner’s Manaul Guide
