Jim’s Tech Talk
by Jim Langley
To set the scene for what we’re covering here in part 2, let’s say we were JRA (just riding along) one fine morning, when, with a “snap” as loud as a rifle shot, a spoke broke in the rear wheel. Or, we could have run through a pothole and damaged the rear wheel.
Either way, we’re now standing safely off to the side of the road with a bike that has a wobbly rear wheel that won’t spin without bumping into the frame. Fortunately, we read part 1 and we own and have the correct spoke wrench for our rear wheel with us. What follows is how to get the wheel straight enough to ride home.
Making the Best of a Bad Situation
Notice that I didn’t say, “fix” the wheel. That’s because sometimes a broken spoke or especially smacking into a hole will damage a wheel enough that it will never be like new again. What happens is that the impact or the spoke failure can ruin the rim (the hoop that the tire mounts on to).
When a rim doesn’t get damaged, it’s possible to fix the wheel like new. And even badly damaged rims can usually be straightened enough to be able to ride home. But, you’ll want to have them replaced as soon as possible. Otherwise they can fail out on the road, which could lead to an accident.
Fixing Wobbly Bike Wheels Basics
All that’s needed to deal with a wobbly rubbing bicycle wheel is a spoke wrench that fits. Whether a spoke broke or a pothole or crash knocked it out, the job is almost the same. The only difference is that with a broken spoke you need to either remove it if it comes out easily, or if not, bend it so it stays wrapped around another spoke and can’t interfere or hit anything when you’re riding again.
After that, you remove enough of the wobble(s) in the wheel to get the wheel to not rub against the frame. This is done by turning the spoke nipples, which tightens or loosens the spokes they’re attached to. This tightening and loosening moves the rim in the area of the spokes the way you need it to go.
Making spoke tension adjustments like this can seem complicated – even scary to beginners. But I’ve found that most people with basic mechanical skills can figure it out on their own through trial and error. I’m going to explain the steps here to help. Keep in mind that the wheel is already damaged and you’re not going to ruin it, so you might as well try to get it going.
The Problem Area Will Be Easy to See
When the wheel is wobbly and hitting the frame it’s obvious that it needs straightening. It’s also clear that the big problem is that the wheel is now hitting the frame. So, what’s needed is tightening or loosening spokes right where the wheel is rubbing to get it to stop rubbing.
Make Small Adjustments
To tighten or loosen spokes, you turn the nipples just a little at a time, about half a turn. Then you check progress and turn again a half turn and repeat until the wobble is improved enough. It’s helpful to keep track of the spoke(s) you are making adjustments on.
Do this by working only on the wobbly area, which will be where the wheel rubs. Don’t let the wheel spin or you will need to find the wobble again. That’ll be easy if there’s only one. But if there’s more, you can lose your place.
Left and Right Spokes
The key thing to know to be able to move the rim the way it needs to go is that there are left side and right side spokes on wheels. Because they’re on either side, tightening and loosening them moves the rim to one side or the other You can figure out whether a spoke is a left or right by following it down to the hub. If the spoke is coming from the left side of the hub it’s a left-side spoke. And rights come from the hub’s right side.
To fix wobbles, you have to make the correct adjustment on the correct spokes. Usually only two or three spokes are affected at each wobble. Because the wheel is damaged or maybe a spoke has broken, what you usually need to do is to either tighten a spoke that has loosened on the side of the wheel opposite the rub. Or, with a broken spoke, you will loosen a couple of spokes on the side that’s rubbing in order to move the rim away.
Focus and Watch What’s Happening
As you tighten or loosen, pay close attention and you will see the rim at the wobbly area start to move slowly. If it moves away from the frame, it means you’re making the correct tension adjustment on the correct spoke(s). If instead the wheel is rubbing worse, you are making the wrong adjustment and need to turn the spoke wrench the opposite direction.
TIP: If you can’t get the wheel to do what you want, the most common mistakes are turning the wrong side spoke or turning the wrench the wrong way and loosening when you meant to tighten or the other way around.
I know that these instructions may sound confusing or too simplistic. Yet, if you can focus on what you’re doing, observe what’s happening and learn through trial and error, you can likely get your wobbler straight enough to ride home on it.
In most cases, wobbles can be removed in a few minutes with only a few turns of a few spoke nipples. When you succeed and ride home you’ll feel great that you fixed it yourself. Then, with luck, and a little practice, you can fix it perfectly later or have a top notch wheelsmith do it for you. Without luck, the wheel may have been too damaged to fix perfectly. In which case it will need a rim replacement.
Mastering Wheel Truing
If you’d like to get good at wheel truing there are many good instructional videos on youtube.com, such as this one from Park Tool https://www.youtube.com/watch?v=sWEbq5Ry63Q It’s not a wobbly wheel hitting the frame situation and it’s not even a road bike, but it does cover the basics of straightening a wheel with a broken spoke nicely.
Ride total: 9,177