Symptoms
- Wheel visibly wobbles when spun with the bike upside down
- Bike feels unstable or shimmies at speed
- Rim brushes brake pads at one point in each rotation
- One or more spokes feel loose when squeezed
Likely causes
- CommonWheel out of true from a loose or broken spokeSpokes loosen over time or break from impact, letting the rim shift out of alignment.
- PossibleLoose hub bearings or axle nutsPlay in the hub itself, separate from the rim, can also cause a wobble feel.
- PossibleBent rim from an impactHitting a pothole hard can bend the rim beyond simple spoke tension adjustment.
What to do
- Flip the bike over or put it on a stand and spin the wheel slowly, watching where it wobbles relative to the brake pads or a fixed reference point.
- Squeeze pairs of spokes together around the wheel to feel for one that's noticeably looser than its neighbors.
- Check the hub for play by grabbing the tire at top and bottom and trying to rock it side to side with the wheel off the ground.
- If a spoke is loose, use a spoke wrench to tighten it slightly, working in small increments and rechecking trueness often.
- If a spoke is broken, it needs replacement before truing, which usually also requires removing the tire and tube.
- Adjust hub bearing preload per the manual if play is found there, or have it serviced.
- If the rim itself looks bent or the wobble is severe, a bike shop should true the wheel or assess whether the rim needs replacement.
Tools and parts
- Spoke wrench
- Truing stand (or bike frame and brake pads as a reference)
Bike spokesSearch: “bicycle spoke replacement correct length”
When to call a pro
Wheel truing takes practice to get right without over-tensioning spokes; a bike shop can true a wheel accurately and replace broken spokes.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.