Tubes

What size inner tube does a BMX take?

Read the tyre sidewall and buy to match. A 20 x 2.2 tyre wants a tube marked something like 20 x 1.75-2.125 or 20 x 2.0-2.4 — the range printed on the box is the span of tyre widths that tube will fill without over-stretching. One step narrow is survivable; going too wide leaves the tube folded on itself inside the tyre, which is a reliable way to pinch it during fitting.

Schrader or Presta on a BMX?

Schrader, nearly always. BMX rims are drilled for the fatter Schrader valve, and you can top up at a garage forecourt without an adapter. A Presta tube will physically fit a Schrader-drilled rim but rattles in the oversized hole and can tear at the valve base, so use a reducing grommet or put those tubes on another bike.

Do you need thick-wall tubes?

Street and park riders usually do. A heavier-gauge or thorn-resistant tube adds well over 100g per wheel but shrugs off the pinch flats you get landing hard on a rim, and it buys time when a tyre is running low on air. Race riders go the other way, since rotating weight on the gate matters more than puncture resistance over a 40-second lap. Kenda, Odyssey, Éclat and Schwalbe all list tubes in more than one wall thickness.

Do new wheels come with tubes?

Rarely. A wheelset or a single front wheel is normally sold bare, sometimes with rim tape fitted and sometimes not, so budget for a tube and check there is tape covering the spoke nipples before you inflate anything. A spoke end through a fresh tube is the most common first puncture on a newly built wheel.

How much should you spend on inner tubes?

Tubes are the cheapest part on a BMX and the one to keep spares of — two in the toolbox and a folded one in your bag. The price differences come down to wall thickness, valve length and whether the core is removable, none of which is worth agonising over. Buy the size printed on your sidewall and put the money into tyres and rims instead.