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Jun 21, 2026 · Germán Guía Delgado

Wheelbuilding fundamentals: spoke length, tensioning order, and de-stressing

Downhill, gravel, road, track: whatever you ride, a handful of habits decide whether the wheel you build stays true for a season or goes soft in a week. Reserve’s John Petricciani, who has overseen something like half a million builds, wrote down a few of these “universal truths” in The Art of Wheel Building. Three of them are exactly what this site’s tools are built around. Below is how to put each one into practice, and where the calculator helps. New to any of the words? The glossary has them.

1. Nail the spoke length before you cut anything

Spokes of the wrong length quietly wreck a wheel. Too short and the nipple can shear under load, or the threads never engage at all. Too long and the spoke end punctures the rim tape (sometimes not on the bench but later, when the rim deflects under a rider), or you run out of thread before you ever reach tension. The margin is small. Spokes are sold in 2 mm steps, and a 1 mm ERD error already moves each side by very nearly 0.5 mm.

So treat the number with respect:

A note on tools. That Reserve piece recommends two spoke calculators, and one of them, the classic Freespoke, is still online and worth a visit. This calculator is a free, open alternative, so you have two to cross-check. The length tool computes left and right independently, shows the math, and makes ERD and offset explicit rather than assuming them. If you only read one more thing, read how to measure ERD.

2. Tension in the right order: leading, then trailing

On a crossed wheel, each spoke is either leading or trailing. Leading spokes lean forward at the top of the wheel and resist braking torque; trailing spokes lean back and pull the wheel along under power. They do different jobs, and the order you bring them up to tension matters.

The common mistake is to tighten every spoke in sequence, once around the rim. That drags the rim’s slack into one spot, the area near the first and last spokes you touched, and leaves you fighting a localised hop, like the bulge that appears when you squeeze a balloon. Instead, build tension gradually across the whole wheel: bring up the leading spokes, then the trailing ones (or the reverse), so the rim is loaded evenly all the way round.

A well-known recipe for this is the Markling Method (after wheelbuilder Sam Markling), which walks the flanges in a fixed order: hand-tight the outboard spokes of the high-tension side, then bring the inboard high-tension spokes to roughly two-thirds, then the inboard low-tension spokes, then the outboard low-tension spokes, and finally the outboard high-tension spokes you started loose. It isn’t mandatory, but it keeps the load even and the build calm.

This is what the truing simulator is for. Turn a nipple, watch the tension redistribute to its neighbours, and see the trueness react, so the cost of dumping all your slack into one spot becomes obvious without risking a real rim. When you build for real, the tension tool gives you a per-side, quarter-turn plan: even each side to its average first, then approach target in passes.

3. De-stress, repeatedly

A wheel’s stiffness comes from the rim plus the tension locked in its spokes, so anything that quietly bleeds tension after you finish is the enemy. Two things do exactly that as you ride. Spokes wind up (twist) as you tension them, and that twist slowly unwinds on the road. And J-bend spoke heads settle into the flange, abrading the finish where they seat; every bit of settling drops a little tension.

De-stressing forces both to happen on the bench instead of on the trail. You flex the built wheel hard, relieve the wind-up, let the heads seat, re-true, and then do it again. It feels like undoing your own work, but the wheel that stays true is the one you put through its paces a few times before it ever touches the ground. (The simulator models how turns redistribute tension. It does not model wind-up, so this step lives in your hands, not the screen.)

The short version

Get the length right before you build. Tension the whole wheel evenly rather than section by section. De-stress until the wheel stops giving anything back. None of this is clever; it’s just the dull discipline that keeps a wheel from going soft. Tension figures from any tool, ours included, are estimates, so re-measure as you go.

Thanks to John Petricciani / Reserve for the original framing, and to Sam Markling for the method that bears his name.

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