Building a new wheel can be very frustrating, but if you know the right way to build it, you’ll be much easier.
Step 1: Prepare everything you need: spokes, the hub, nipples, the rim, a screwdriver, the spoke wrench, a ruler, the upside-down bike frame.
Step 2: The next thing is you shall recognize four groups of spokes – the left-side, the right-side, the back-side and the front-side. What you need to do is to put in all the freewheel-side trailing spokes. Grab the hub with the freewheel body towards you, and insert nine spokes in alternate holes on the freewheel wide of the hub. Remember to insert from the outside so that the spokes can run from the inside of the holes.
Step 3: Get the rim with the label facing towards you. Look at the holes, and you’ll find that they alternate sides rather than being centered. Find the first hole on your side to the right of the valve hole. Insert a spoke and screw on the nipple. Remember not to tighten the nipple for real; just screw two or three turns. Then grab the spoke to the right and attach it four rim holes to the right so there are three empty holes between this and the previous spoke. Repeat this step for all nine spokes, and then check the spacing.
Step 4: Turn the wheel around, and do the same in mirror-image for the left side. Each spoke should run from the flange hole just in front of the occupied one the right side, and run to the rim hole directly in front of the corresponding occupied one. It is very difficult to understand from the literal. If possible, you can download a picture of bike wheel from the internet and compare it with the previous one. It would be better for your understanding. Do this for all nine spokes. Get the hub and turn it forward a little. The spokes should to taut, giving you an idea of their final position and angle in the finished wheel. Looking for one side, there should be no spoke crossing each other at this point.
Step 5: Take the wheel with the freewheel towards you. You need to put in the nine front spokes on this side. Each spoke should be across three of the existing spokes on this side. Insert the spoke from the inside of the flange, and the run it forward on the outside of two existing spokes and behind a third. Attach to the rim at the next available freewheel-side hold.
Step 6: Repeat in mirror-image for the left side of the wheel. At this time, only one set of holes is available in the rim. Check twice the spoke pattern. Don’t insert them wrong.
Step 7: Tighten all the nipples with your finger so that the threads just disappear. This step is to get all of the spokes at the same very moderate tension. If the wheel is still very floppy after that, screw on each nipple another turn. Then put the wheel in the frame, spin it, and observe it to see how wobbly and off-center it is.
Step 8: Spin the wheel, and use the ruler to brush against the rim to find where the wobbles are. Then fix whichever is worst at any one time. Pull a section of the rim toward one side by screwing on spokes on that side with the spoke wrench while loosening spokes on the other. In order to correct vertical straightness, find the lumps and tighten spokes equally on both sides. Keep on doing this step until the wheel is pretty straight both laterally and vertically to within a couple of millimeters. The spokes should now be tighter than before.
Step 9: Now you have a straight and centered wheel, but the spokes are a little loose. Get another wheel and pluck the spokes. Listen carefully to the note and compare it with the note from your new wheel—normally the freewheel side will be higher in pitch. Now tighten all the spokes equally, until the pitch is in the same note as the reference wheel. You can also judge the tension by squeezing pairs of spokes together. After this, get groups of four spokes and squeeze them until the spokes stay bent around each other. Keep on doing this to true the wheel over and over again until the incongruous noises stop and the wheel stays true. Mount a tire on it.