Truing Wheels

1. See Fig. 2C-17 and proceed as follows. Use wheel axle as a truing arbor; insert in wheel hub and place wheel in Truing Stand, Part No. 95500-29.

2. Front Wheel: Starting at valve hole, tighten all nipples opposite brake flange side until end of spokes are approximately 1/16 in. from being flush with head of nipple. Use Nipple Wrench, Part No. 9468139.

3. Rear Wheel: Turn each nipple on just far enough to cover spoke threads. Start at valve hole and tighten all nipples three full turns each. Then, proceed to tighten all nipples one full turn at a time until spokes are snug in wheel.

4. Front and Rear Wheel: Check rim for concentricity, centering sideways with hub and for running true sideways (Fig. 2C-17 and 2C-18). Centering rim sideways must be done as one operation. Rim must be properly centered sideways in relation to hub for correct alignment and "tracking" of wheels.

Figure 2C-18. Truing Rim Concentric with Hub

Figure 2C-19 and 2C-19A show method of using a straight edge to determine correct sideways centering of wheel rim. If rim is too close to straight edge, loosen all nipples on brake side and tighten all nipples on opposite side same amount. If rim is too far from straight edge, reverse operations. Lay straight edge across brake side as shown and measure distance from straight edge of rim. When rim is correctly centered, this distance will be as shown for each wheel listed.

Adjust truing stand gauge (Fig. 2C-17), to side of rim well so rim at highest point will strike gauge as wheel is rotated slowly. Loosen nipples at highest point of rim on gauge side, and tighten nipples on opposite side the same number of turns. Repeat this operation until rim runs true sideways. Reverse loosening and tightening of nipples, as explained above, if rim moves too far away from gauge. After each loosening and tightening of spokes, check rim in relation to hub as shown in Fig. 2C-19. Rim should be trued sideways to within 1/32 in.

After rim has been centered sideways with wheel hub and runs true sideways, check for concentricity. Adjust truing stand gauge (Fig. 2C-18) to rim tire bead seat. If rim runs eccentric (radial runout) nipples must be loosened at points rim does not contact gauge, and nipples tightened at points rim contacts

(1964 and Later)

Figure 2C-19. Aligning of Wheel with Straight Edge (1963 and Earlier)

(1964 and Later)

gauge. Amount nipples are to be loosened or tightened is determined by the amount rim is out of round. Rim should be trued concentrically to 1/32 in. or less radial runout.

5. After wheels have been checked and corrected as described in paragraph 4, start at valve hole and tighten nipples one turn at a time all the way around rim until spokes are normally tight. If possible compare with a new wheel. While tightening nipples, repeatedly check rim with gauge according to instructions under paragraph 4.

6. After all nipples have been pulled up, until spokes are normally tight and wheel is true, seat each spoke head into hub flange with a sharp blow, using a flat nose punch and hammer. Then retighten all nipples and finish truing wheel. This method allows spokes to be drawn tighter at the start and prevents possibility of spokes loosening after wheel is put into service as the result of spoke heads seating into the flange.

Do not tighten spokes too tight or nipples may draw through rim, or hub flanges may be distorted. If spokes are left too loose, they will continue to loosen when wheel is put in service.

7. File or grind off ends of any spokes protruding through nipples to prevent puncturing tube when tire is mounted.

0 0

Post a comment