To true a wheel you adjust spoke tension with a spoke wrench: tightening the spokes on one side pulls the rim toward that side. Fix lateral wobble first (the side-to-side movement) and then radial hop (the up-and-down movement), always a quarter turn at a time. Park Tool sets the target at 0.5 mm of lateral deviation and 1 mm radial. And there’s a limit: if the rim is bent from an impact, no amount of spoke adjustment will fix it.
Lateral, radial and tension: what you’re fixing
| Problem | What it looks like | How to fix it |
|---|---|---|
| Lateral wobble | The rim moves toward one side and then the other as it spins | Tighten spokes on the side opposite the wobble (or loosen on the same side) |
| Radial hop | The rim moves up and down; the bike bounces at certain speeds | Tighten pairs of spokes at the high spot, loosen at the low spot |
| Uneven tension | Spokes sound different when you pluck them | Even out tension while keeping the rim straight |
| Dish | The rim isn’t centered between the axle locknuts | More tension on one whole side of the wheel |
Park Tool points out that lateral wobble is most critical on rim brake bikes, because the rim rubs the pad. With disc brakes, it’s the rotor that rubs, not the rim, but an out-of-true wheel still loads the spokes unevenly and can rub the frame with wide tires. If what’s rubbing is the rotor and the wheel is straight, the fix is in the caliper: we explain it in disc brakes.
What you need
- A spoke wrench in the exact size of your nipples (the nuts on the spokes). A wrench that wobbles will round off the nipple.
- A truing stand or, failing that, the bike itself with a fixed reference: a rim brake pad or a zip tie on the chainstay or fork.
- A spoke holder if your spokes are bladed or straight-pull, so they don’t twist with the nipple.
- A tension meter (like the Park Tool TM-1) if you want to measure tension instead of guessing.
- Oil or light lube for the nipple threads.
Before you touch anything, remove the tire if you can, or let most of the air out. Check for broken or loose spokes: if one is broken, replace it first. The spoke length calculator tells you what length to buy.
Which way to turn the nipple
This is where everyone gets confused. Looking at the nipple from outside the rim (from where the tire sits):
- Clockwise: tightens the spoke.
- Counterclockwise: loosens it.
With the wheel in a truing stand or the bike upside down, the nipple is at the bottom and the turn looks backward. Park Tool specifically warns about this. Tip: before you start, turn one spoke a quarter turn and watch which way the rim moves.
Lateral truing step by step
- Find the worst spot. Spin the wheel slowly and bring the reference (the truing stand caliper, the brake pad or the zip tie) in until it just touches at the point of greatest deviation. Mark it with tape.
- Find the spokes responsible. At the center of the wobble, pick the spoke that goes to the side opposite the wobble.
- Tighten that spoke a quarter turn (90°). Park Tool suggests a half turn only for big wobbles and an eighth for small ones. The spokes on either side of the spot get less.
- Tighten rather than loosen. Park Tool explains that loose spokes tend to keep loosening, while tight ones stay where they are.
- Spin the wheel again and find the next worst spot. Make about three corrections on one side before moving to the other.
- Keep moving the reference closer as the wheel improves, until you’re at about 0.5 mm of deviation.
Radial truing step by step
- Find the high spot: bring the reference in under the rim until it touches where the rim rises most.
- Tighten pairs of spokes from both sides in that area, a half turn each: pulling from both sides at once brings the rim down without pulling it sideways.
- At low spots, loosen pairs of spokes the same way.
- Recheck lateral true every three or four radial corrections, as Park Tool recommends.
- Stop when the hop is 1 mm or less.
Spoke tension
A straight wheel with very uneven spoke tension won’t stay straight: over the miles, the loose spokes give and the wobble comes back. So while truing, try to keep spokes on the same side at similar tension. Squeezing them in pairs gives you a decent feel, but the reliable way is a tension meter: the reading converts to kilograms of force with the manufacturer’s chart or the Park Tool app.
How much tension? Whatever the rim manufacturer specifies, since the rim is the limiting part. There’s no universal number: a light carbon rim and an aluminum touring rim take different values, and a rear wheel runs more tension on the drive side than on the non-drive side.
When you’re done, Park Tool advises stress-relieving the spokes by riding: install the wheel and go for a spin. A few pings in the first pedal strokes are normal. Check the true afterward.
When it can’t be fixed
- Bent rim. Check tension at the spot that got hit: if the spokes on the side the rim leans toward are already loose and those on the opposite side are very tight, the rim is bent. Park Tool is blunt: spokes don’t fix a bent rim, and forcing the tension leaves a weak, dangerous wheel. The rim has to be replaced (the hub is usually fine to reuse).
- Seized nipples. If the threads are corroded, the nipple won’t turn or the spoke twists with it. Lubing the threads now and then prevents it.
- Several broken spokes. With one, replace it and true the wheel; with three, Park Tool recommends rebuilding or replacing the wheel.
- Carbon wheels or special spokes. Many have internal nipples, proprietary spokes or high tension. Better left to a shop with the manufacturer’s manual.
Common mistakes
- Turning the wrong way because the wheel is upside down. Test a quarter turn first.
- Turning full turns. A quarter turn already moves the rim; more, and you swap one wobble for another.
- Truing by loosening only. The wheel ends up straight but soft, and goes out of true on the next ride.
- Using a wrench that doesn’t fit and rounding off the nipples.
- Forgetting radial true. A wheel with no wobble but a hop vibrates and wears the tire unevenly.
- Riding on with a broken spoke. Its neighbors take more load and break next.
Check true and spoke tension every 600 miles (1,000 km) as part of your maintenance schedule by mileage. If you’re also changing the tire, the guide to bike tire pressure helps you get it right. The names of nipple, spoke and rim in six languages are in the wheels and tires glossary.
Frequently asked questions
Which way do you turn a spoke nipple to tighten a spoke?
Looking at the nipple from outside the rim (from the tire side), clockwise tightens and counterclockwise loosens. With the wheel in a truing stand or the bike upside down, the motion looks reversed: always think from the nipple's point of view.
How much wobble is acceptable in a bike wheel?
Park Tool suggests 0.5 mm or less of lateral deviation (about five sheets of paper) and 1 mm or less radial (about ten). They're guidelines: with disc brakes, a little more lateral wobble won't rub.
Can you true a wheel without a truing stand?
Yes, with the wheel on the bike: use a rim brake pad or a zip tie fastened to the chainstay or fork, close to the rim, as your reference. It's less precise than a truing stand, but it works for fixing a knock.
How many broken spokes can a wheel have?
Replace a broken spoke and retrue the wheel. Park Tool's rule is that with three broken spokes the wheel should be rebuilt or replaced, because the rest are fatigued too.
How do I know what length spoke to buy?
Measure the broken spoke or, better, calculate it from the hub and rim dimensions (effective rim diameter, flange spacing and number of crosses). Our spoke length calculator does it with the classic formula.