a fuel needle valve assembly of a carburetor has a retainer which yieldingly restrains the rotational fuel flow setting capability of the needle valve . the retainer engages a shank of the needle valve and a parallel shaft , both of which project from the carburetor body . the retainer exerts a force which laterally displaces the projecting shank with respect to the shaft . the retainer has sufficient strength to ensure the factory set rotational setting of the fuel needle valve does not alter when a limiter cap is press fitted to a distal head of the needle . furthermore , wherein the shaft is also a shank of a second needle valve , the same retainer laterally displaces the projecting shanks of both needle valves .