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One of the most satisfying repairs for a home bicycle mechanic is building a wheel. Once you can do this, you no longer worry when a wheel gets knocked out of true, because you have the skills to fix it. And you ride knowing that if the worst happens and you hit a hole or crash and mangle your wheel, you can put together a new one. In most cases, to build a wheel you dont have to be a wheelbuilding expert versed in choosing the right length spokes, the proper lacing patterns and lacing techniques (though if you want to become a true wheelsmith, I provide extensive instructions for that too). Instead you just need to know the easy way to build a wheel, which
is called rim replacement, and is the subject of this article. Its
something well within the capabilities of most home bike mechanics.
Overview of the procedure I call this easy wheelbuilding because it eliminates the tricky part of wheelbuilding from scratch with a hub, rim and spokes. For that, you need to figure out what length spokes to use, and lace the wheel with the new spokes. Unless your wheel is really old (three to five years) and has seen lots of use and abuse, you can likely reuse the spokes in your wheel, which is what I recommend for this type of wheelbuilding because it simplifies and speeds the job and results in another great wheel (as long as the spokes are still good). But the thing that truly makes this technique so easy is using the identical rim brand and model as the damaged one you are replacing. You take this new rim and tape it right next to the damaged rim and then move the spokes from the old rim to the new. Onced youve trued and tensioned the wheel youre done! Step-by-step instructions follow.
1. Remove the damaged wheel and use your tire levers to remove its tire
and tube. Take off the rim strip, too. Place a drop or two of oil inside
each nipple from the top (tire side) and add a little below where the
spoke enters the nipple. Also, put a small dab of grease on each spoke
hole in the new rim. 4. Now for the fun part: one at a time, and starting at the valve hole, transfer the spokes from the old wheel into the new rim. Use the screwdriver inserted in the flats on the tops of the nipples to turn them if you need to. And only thread the nipple onto the spoke in the new rim about 3 turns. Keep going until all the spokes and nipples are in the new rim and the old rim is ready to become a wall decoration. |
TOP VIEW clockwise tightens counterclockwise loosens |
Truing the bicycle wheel 5. To true and tension the wheel, youll use your bicycle as a wheel truing jig (it works great). Install the wheel on the bike (dont put on the tire/tube yet) and support the bike so you can spin the wheel youre working on. You might hang it or put it on your car rack or hook the seat over a tree branch. Just be sure to locate it so that the wheel is held steady and so that
you can comfortably work on it. Shine a lamp on the wheel so you can
see what youre doing if youre working inside. Note though that its easy to get confused if the nipple moves to the other side, like if the wheel rotates. So, a good way to work is to always rotate the wheel to bring the nipple you want to turn to the top of the wheel so that youre looking down on it. In that position clockwise turns will always tighten, and counterclockwise ones will loosen. |
Put the wheel in the frame or fork to
true it and use your thumb as an indicator to find wobbles in the spinning
wheel. To move the rim right, loosen spokes on the left and tighten
spokes on the right and vice versa. |
7. Spin the wheel. Rest your thumb against the frame or brake (see illustration; brake not shown) so that you can see how wobbly the wheel is. Find the worst wobble and stop the wheel holding the wobble next to your indicator (your thumb or the brake) because thats the part of the wheel youre going to work on first. To move the rim right, loosen spokes in the area of the wobble on the left side, and tighten spokes on the right and vice versa (to move the rim left). But read step 8 and reread the note in step 6 first to avoid the truing mistakes that are so easy to make if youre not careful. |
Notice that there are spokes on the right and left sides of the wheel. When truing, always pay attention to which side the spoke is on and turn the correct nipple. |
8. Note that there are spokes that originate on the right and left side of the hub (drawing). This is important. Never make an adjustment to a nipple until youre sure which side of the wheel the nipple/spoke is on. As mentioned in step 7, adjustments are made by loosening and tightening nipples in the area of the wobble. Follow these rules: To move the rim to the right, loosen the nipples (at the wobble) on the left side of the rim and tighten the nipples on the right side of the rim. Vice versa to move the rim to the left. Always turn the nipples in quarter- to half-turn increments, then spin the wheel and see how you did. Then repeat. Follow these rules and remove the wobbles until the wheel spins past your thumb with no significant wobbles. Think about what youre doing. Focus. Take your time. Be patient.
Enjoy the process of gently truing the wheel to perfection by skillfully
fine-tuning the tension of the spokes. It takes a little practice to
become a wheel wizard, but you can do it. Remove low spots first by slightly loosening spokes in the area. Then slightly tighten the spokes at the high spots. Gradually, the wheel will get round. Youll then need to check side-to-side straightness one more time. |
While truing and tensioning its important to gently stress-relieve the spokes by going around the wheel and squeezing parallel pairs of spokes. This allows the spokes that have gotten twisted during the truing process to unwind and also seats the nipples in the rim and the spoke heads in the hub. |
Tensioning the wheel 10. To finish the wheel, you need to tighten all the spokes to the point where they wont loosen. Its called tensioning the wheel. Start at the valve hole and turn every spoke nipple a half turn tighter. As long as you turn an even amount on each nipple, the wheel will remain true and round. If youre working on the rear wheel, which has different tension on the right and left sides (due to the rim being centered over the axle instead of the huba condition called dish) turn the cassette-side nipples a half turn but only turn the left-side ones a quarter turn. The goal is to end up with the rim exactly centered in the frame. After each round of tensioning, go around the wheel grabbing parallel
pairs of spokes in you hands and squeeze them gently to stress relieve
the spokes (illustration), seat them in the hub and rim and unwind any
spokes that got twisted. Repeat the rounds of tensioning until when
you grab the spokes, they feel as tight as the spokes on your undamaged
wheel. Install the tire and tube and youre ready to roll. Well
done, Wheelbuilder! |