Alright. So you may have found that your wheel is not rolling between your brakes properly. It's basically out of true, so it's kind of wobbling back and forth. That could be just because the wheel is out of true, or it could be because a spoke is broken. Spokes usually break at two spots. The most common spot is right here at the bend. That's the weakest point. Sometimes it breaks right here where it reaches the spoke nipple.
What you can do is you can take your rim and kind of feel around. As you can see this is the broken spoke here. You kind of feel around. See if there are any more broken spokes. If you have one broken spoke you can replace it. If you have two or three usually you need to replace the wheel. It could be very far out of tension. Basically all these spokes should be almost exactly the same tension.
So, what you're going to do is you're just going to pull the spoke out making sure that you're not scratching the rim if you have a very nice rim. You're going to size up the spoke. What you can do is use a ruler or whatever you have at home that can read in millimeters. This is a spoke ruler, so it shows us the exact amount. This spoke is 299 millimeters.
What you do is you go into a bike shop. Or, if you have one laying around that is the right size spoke then you take that spoke. Make sure you have a little bit of spoke prep on the threads so it'll stay in the nipple properly. Get your spoke nipple. You're going to thread the spoke through the wheel just as it looks with all the other spokes, the same pattern.
There are a couple of different patterns. It may be a radial pattern which basically means the spoke goes straight out. A 2-cross crosses two spokes. This is a 3-cross which is probably the most common. So, you want to make sure you're doing the exact same pattern.
The spoke is through, and you can put your spoke nipple in and thread it onto the spoke.
This is a more advanced process. You're going to want to make sure that you take a class on this or that you're working with somebody who's very experienced, maybe a former bike mechanic or a current bike mechanic. Because you can really mess up your rim and cause a lot of damage. It could be very, very pricey.
Once you have the spoke on then you're going to re-tension it and put it on a truing stand and make sure that the wheel is nice and true. Also, you want to make sure that, once you're done with that, you put the rim strip back in. Basically, there are two types of rim strip. This is a single walled rim. So, you can see there's just one wall inside, and the spoke nipples are very exposed. That you can use just a rubberized rim strip. Sometimes these get really brittle over time, so you want to make sure you replace them. That may be why your tube goes flat, because the spoke nipple has actually cut the tube and you need a new rim strip.
If it's a double walled rim, which basically means it has two walls, you can see the difference, the two differences in rims. One is single wall, and then the other one double wall. A double wall rim you need to make sure that you're not using the rubberized rim strip. You need to be using a cloth rim strip or something that's much stronger so the tube doesn't push into the holes and cut the rim strip.
And that's how you replace a spoke.