Garage Files: Replacing a spoke and truing your wheel

Garage Files

When you break a spoke it becomes one of the most frustrating bicycle repairs. There are so many things affected besides the spoke itself. To replace the spoke(s) you must remove the tire, tube and rim strip to get to the nipple and you must remove the brake rotor and/or cassette on the back wheel to get the spoke laced through the hub. Once installed, you must tension the spokes properly to bring the rim into true. This process requires a little bit of patience and thinking, but is very easily accomplished in the comfort of your own garage. Making small adjustments at a time is the rule of thumb, so don’t attempt to straighten your rim in one step.

Tools needed:

Wheel truing stand, spoke wrench, rim tape, tire lever, spoke prep, tire sealant, cassette tool and torx, allen or center-lock tool for disc if necessary to remove based on broken spoke location.

Remove wheel from bike.
Remove the tire
Remove the brake rotor and/or cassette if necessary. This may not be necessary depending on the broken spoke’s location.
Remove rim tape.
Remove the broken spoke from the rim. Take a look at the damaged spoke in your wheel and all of the spokes near it to see if they’ve also received any damage or compromise. A nick or even a bend can weaken a spoke and make it the next failure point. If any other spokes are damaged, we recommend replacing them at this time as well.
Remove the broken spoke and measure the spoke length if both pieces are available and straight enough. Spoke length is crucial. If the broken spoke is too damaged or you are missing pieces then you can remove the next spoke from the wheel, on the same side of the hub (the second nipple away), measure it and replace it pretty easily without much effect.
Cut the spoke to desired length, or order it from your local shop if you do not have the tools or ability. Remember every wheel has different spoke lengths and most of the time spoke length varies on each side of the hub as well as cross patterns. So pay attention to which side and location you are replacing, especially if you are doing multiple spokes at the same time.
Lubricate the spoke threads with spoke prep, or if unavailable, chain lube. There are a number of different-sized spoke nipples, therefore, an equal number of tools. Most spoke nipple tools are color coordinated. Make sure you are using the proper-sized spoke tool and that it is snug on the nipple. Install the new spoke and match the over/under cross pattern of the rest of the wheel exactly. Screw the nipple onto the spoke using a spoke tool until you feel snug resistance. It is extremely easy to round out the spoke nipples, especially the aluminum ones, and that creates a much bigger project. Be extremely slow and patient with your wheel truing, it will save you much more time in the end result. You’ll find it easier to true at the bottom of the wheel in the stand.

 

Mount the wheel into the truing stand with the drive side on your right as you face the stand.
Raise the truing stand calipers to match the outside of the rim. Gently spin the wheel with the calipers open enough to not make contact with the wheel; then tighten the caliper tips while gently spinning the wheel, allowing them to make light contact with the most-out-of-true section of the rim.
At the point where the caliper makes contact with the rim, locate the spoke that originates from the opposite side of the hub.

 

Spoke nipples turn clockwise on the spoke, so remember the direction of the nipple will seem different if you are tightening at the bottom or top of the rim, but it will always turn the same direction on the spoke. Try to make small adjustments. Be patient, and do not try to straighten the rim all in one move. Remember that as you tighten the spokes, you are pulling the rim closer to the hub, which can create a hop in the wheel as it increases the length on the opposite side of the wheel. This can be hard to fix, so take your time and make minor adjustments.
Tighten the nipple on that spoke until it pulls the rim away from the caliper, truing the wheel in the process.
You may need to loosen the two nipples on either side of the affected spoke a half turn (180 degrees) to relieve tension before tightening the spoke causing contact with the caliper.
Spin the wheel again and repeat steps 11 and 12. If you have multiple sections out of true, you will do the same procedure on each of them. Remember to look at the hub side opposite of the point where the rim is making contact with the caliper. When you tighten the nipples on these spokes, they will be pulling the rim away from the caliper. Be careful not to over-tighten the nipples and pull the rim too far in the opposite direction.
Your wheel is within true spec when it is within 1mm from caliper to rim around the whole wheel.
Install rim tape on a tubeless wheel—or a rim strip, if you are using a conventional tube.
Install the tire and add sealant if necessary.
If you removed the cassette and brake rotor, reinstall them as well.

Success! You can now go out and ride with confidence and comfort knowing that you handled the job yourself! (Note: If this job seems too overwhelming for you, remember that your local bike shop will probably only charge you about $25 for this repair.)


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