Inner tubes

BMX inner tubes: the consumable never to overlook

It is the cheapest part on the bike and the one that ruins a race day when it lets go. A tube of the right size, correctly inflated and protected by sound rim tape, lasts a whole season. A tube too narrow for its tyre fatigues along the folds and gives way on the first heavy landing.

20 inch inner tubes

The 20 inch size covers most of BMX race, with two rim diameters never to be confused: the 406, run in wide 1.50 to 1.75 sections, and the larger 451, paired with the narrow 1"1/8 and 1"3/8 sections of the Mini to Expert classes. A 406 tube will not fit a 451 rim: the diameter differs, even when the stated width looks similar.

24 inch inner tubes

For the 24 inch Cruiser (507 rim), the usual sections are 24x1"3/8 and 24x1.75. Riders who alternate between 20 and 24 inch across the season should store the two formats separately: deflated, a 24 inch tube looks a lot like a 20 inch one.

Presta or Schrader, and which stem length

Valve type depends on the rim drilling, not on preference. A rim drilled to the small diameter will not take a Schrader valve.

• Presta: slim valve with a knurled lock nut, precise at high pressure, adaptor needed on some pumps
• Schrader: wide automotive-format valve, works with every pump and every club compressor
• 40 mm: enough on a low-profile rim
• 60 mm: essential on deep-section carbon rims, otherwise the valve head cannot be reached

Butyl or latex

Butyl is the standard material: inexpensive, it holds pressure for days and can be patched. Latex tubes, thinner and more supple, take weight off the wheel and roll better on hard ground, but they deflate naturally between sessions and demand a pressure check before every ride. That makes them a race-day choice, not a training one.

Choosing the right width

Read the section printed on the tyre sidewall and take the matching tube, or the one whose range covers that figure.

• 1"1/8 tyre: 1"1/8 tube
• 1"3/8 tyre: 1"3/8 tube
• 1.40 to 1.50 tyre: 1.50 tube
• 1.60 to 1.75 tyre: 1.75 tube

If you are torn between two sections, the size of your BMX tyres settles it: a slightly narrow tube beats an over-wide one that creases inside the casing.

Fitting, care and service life

Inflate the tube slightly before seating it in the tyre and it drops into place without twisting. Check that the rim tape covers every spoke nipple and sits centred on the valve hole: that is the number one cause of repeat punctures on the rim side. Check pressure before every session and replace a tube as soon as the valve base starts to lift — that area cannot be repaired. Always keep a new tube and tyre levers in the bag.

The BMX RACING advice

Give us your wheel size, your tyre width and the valve type your rim is drilled for: we confirm the right reference, and the inflation adaptor if you are moving from Schrader to Presta. Our BMX rims listings state the valve drilling for each model. Dispatched within 24 to 72 hours and you can spread the cost over 2 or 3 payments available.