Harley Davidson Sportster (1959 to 1969). Service manual — page 8

Turn the entire body upside down, drop in the idle tube (28), small end first, jiggle the body, and the tube will locate itself in the body hole. Do not bend, twist or damage the idle tube in any way. Press on plug end of tube until tube is seated and the bottom of the plug extends approximately 1/32 in. out of nozzle passage. When installing bowl nut (26) and gasket (27), spring tension will hold the idle tube firmly in place.

Assemble support bracket (25), nut and lock washer (24).

CARBURETOR BOWL

Assemble bowl to carburetor main body with four attaching screws (16) and gasket (18).

THROTTLE BODY

Install throttle shaft (13), counterbored screw head notches facing towards carburetor main body. Position throttle disc (8) in shaft, milled side up and facing carburetor body. Insert and tighten shaft screws (7). Work disc several times. If there is any binding, loosen screws and reposition disc.

Install only replacement throttle disc containing same identification number on face. With disc correctly installed and closed, the number will be on top half of disc facing carburetor main body.

Install screw (14) and spring (15). Assemble throttle lever to shaft (10) with spring (11) and washer (12) allowing slight end play in the shaft when lever assembly is clamped tight. Position throttle disc and throttle lever in wide open position before tightening screw (9).

Install low-speed needle valve (4), washer (5) and spring (6). Be careful not to jam the low-speed needle point into its seat. Install idle hole body plug (3). Install idle passage tube (36) in carburetor body, chamfered end out. Install a new throttle body gasket (2), position throttle body in place and insert screws and lock washers (1).

The Model DC carburetor is attached to the manifold flange with certain thickness gasket and certain length cap screws. If for any reason the overall gasket thickness is reduced and no change is made in the cap screw length, the cap screw may bottom on the head of the lower throttle body screw (1). If it does bottom, a broken throttle body will result.
After assembly, adjust carburetor as described in "Adjusting Carburetor."

All pertinent calibration and setting figures not given in prior information appear in following chart.