Wheel Truing & Spoke Tension Basics

"True" is really two separate measurements

A wheel being "true" or "out of true" is often talked about as one simple thing, but it's actually two genuinely independent measurements. Lateral trueness is side-to-side wobble as the wheel spins, viewed head-on — the classic "the wheel is wobbling" complaint. Radial trueness is roundness — up-and-down movement (hop or bounce) as the wheel spins, viewed from the side, which is a completely different symptom from a lateral wobble. A wheel can be laterally true and radially out (a smooth-tracking but bouncy wheel) or the reverse, which is why a proper truing stand checks both independently with separate indicator points, rather than eyeballing one and assuming the other is fine too.

The basic direction rule for correcting a wobble

Spokes are under tension, and tightening a given spoke pulls the rim slightly toward that spoke's side of the hub. To correct a lateral wobble, the general rule is to tighten spokes on the side opposite the deviation — pulling the rim back toward true from the side it's currently drifted away from — rather than loosening spokes on the side it's wobbling toward. There's a well-known beginner trap worth knowing about here too: viewed from outside the wheel, clockwise tightens a spoke nipple, the way you'd expect — but when you're working a nipple from a truing stand looking through the wheel from the inside, that same clockwise-tightens relationship looks reversed from your point of view, which is a very easy way to accidentally loosen a spoke you meant to tighten.

Spoke crossing patterns, and why radial lacing has a hard restriction

Wheels are laced in patterns named by how many other spokes on the same hub flange each spoke crosses on its way to the rim — "cross 3," "cross 2," and radial ("cross 0," where the spoke runs essentially straight from hub to rim with no crossing at all). Higher-cross patterns lay spokes more tangentially against the hub flange, which better resists the twisting/torque loads that come from pedaling or from a hub-mounted brake (a drum, coaster, or disc hub brake, which loads the hub differently than a rim or rotor brake through the frame); lower-cross patterns, down to radial, sit closer to perpendicular to the hub. This isn't just a cosmetic choice: a radially-laced wheel is suitable only for a front wheel with no hub brake — a driven wheel, or any wheel carrying a hub-mounted brake, should never be radially spoked, because the near-perpendicular spoke angle concentrates far more stress under torque than the pattern is built to handle, risking spoke or even hub-flange failure over time.

How BuildMyMTB checks this

None of this — lacing pattern, spoke count, or truing state — is something the compatibility engine checks or models, and it can't be, because wheels are sold in the catalog as complete, already-built units rather than a hub, rim, and spoke set you'd assemble yourself. This guide is background knowledge for understanding a wheel you already own or are considering having built, not something the builder verifies as part of a compatibility verdict.

Practical takeaways

• If a wheel feels bouncy rather than wobbly, that's a radial-trueness issue, which is a different check (and often a different fix) than a lateral wobble.
• Remember the tightening direction looks reversed when you're looking at a nipple through the wheel from a truing stand, versus looking at it from outside the rim — a common source of accidentally making a wobble worse.
• Never accept or request a radially-laced rear wheel, or any wheel with a hub-mounted brake — it's a front-wheel-only, no-hub-brake pattern for real durability reasons, not a style preference.