Spoke Nipples

Spoke and Nipple Buying Guide

Spokes and nipples are the tension members that connect hub to rim and keep the wheel round, true and stiff. Individual spokes are cheap replacement parts — the real cost is the labour of truing the wheel after a replacement. Understanding spoke types, lengths and nipple materials helps whether you're building wheels or just replacing a broken spoke trailside.

Spoke Types

J-bend spokes have a 90° bend at the hub end that hooks through the hub flange — the traditional and most common spoke type. Straight-pull spokes have no bend and slot into straight-pull hubs (DT Swiss 240/180, some Mavic) — they're slightly stronger because there's no stress concentration at the bend, but they limit you to straight-pull hubs. Butted spokes (DT Swiss Competition, Sapim Race) are thicker at the ends and thinner in the middle — lighter and more fatigue-resistant than straight-gauge because the thin middle section flexes instead of concentrating stress at the elbow.

Spoke Length

Spoke length depends on the hub flange diameter, rim ERD (effective rim diameter) and the lacing pattern. Every hub-rim combination requires a specific spoke length calculated with a spoke calculator (DT Swiss and Sapim both offer free online tools). Lengths are measured to the nearest millimetre. Wrong spoke length means the nipple either bottoms out on the spoke thread (too long) or doesn't have enough thread engagement (too short) — either compromises the build.

Nipple Materials

Brass nipples are heavier (1g each vs 0.3g for alloy) but much stronger and easier to work with. They don't corrode onto aluminium rims and they don't round out under a spoke wrench. Alloy nipples save 20-25g per wheel but can seize in the rim, strip more easily, and corrode in wet conditions. For MTB use — especially in UK weather — brass nipples are the better choice. The 20g weight penalty is meaningless compared to the reliability gain. Alloy nipples make sense on XC race wheels where every gram is scrutinised.

Replacing a Broken Spoke

Carry a spare spoke and a spoke wrench on rides. If a drive-side rear spoke breaks, the wheel will pull out of true toward the non-drive side — it's usually rideable but will rub the brake caliper. Thread the new spoke through the hub flange, match the lacing pattern of the neighbouring spokes (over-under-over or under-over-under), thread the nipple on, and tension to approximately match the surrounding spokes. A proper retension and true at home finishes the job.