Rims

BMX race rims: profile, material and drilling

The rim decides much of how a wheel behaves. Its weight, sitting far from the axle, is felt directly under acceleration and in every change of rhythm. Its lateral stiffness governs how the bike holds a berm, and its profile shapes the way it takes a landing you got wrong.

Carbon rims

Carbon offers the best stiffness-to-weight ratio and allows deep profiles without a weight penalty. The gain shows most out of the gate and in straight-line accelerations, on profiles of the Avian Venatic or Ikon type. In return, a hard impact more often means replacement than repair, and a visual check after a crash is essential. It is a coherent choice for a rider who puts power down and races regularly.

Aluminium rims

Aluminium remains the reference for training and in the younger classes. An alloy rim buckles rather than breaks, comes back true with spoke adjustment, and costs a fraction of carbon to replace. Recent double-wall profiles, such as the Sun Ringle Envy or Ikon Ultralite, hold high tensions and stay fully competitive up to Expert.

Sizes: 406, 451 and 507

• 20 x 1-1/8" and 20 x 1-3/8" (451 rim): large diameter, narrow sections, Mini to Expert
• 20x1.50 and 20x1.60 (406 rim): intermediate profile, versatile
• 20x1.75 (406 rim): wide sections, Pro and Pro XL classes
• 24x1.50 to 24x1.75 (507 rim): Cruiser only

451 and 406 are not interchangeable: tube, tyre and rim tape all have to follow the diameter you pick.

V-brake or disc

Rim profile depends on the braking system fitted to the bike. A V-brake rim has a machined braking track on its sidewalls, made to take pads. A disc rim has none: its sidewalls are free, which allows a more aerodynamic and slightly lighter profile, but it cannot be braked on the rim. A few models accept both set-ups. Check this alongside your configuration in our BMX brakes section.

28H or 36H, and hub compatibility

Rim drilling has to match hub drilling exactly: you cannot lace a 36H rim to a 28H hub. A 28H build saves weight and suits lighter riders and the Expert classes, with a front wheel that sees less stress. A 36H build spreads the loads better and is the sensible rear choice for Pro, Pro XL and heavier riders. Mixing 28H front with 36H rear is common and perfectly coherent.

Compatibility to check before ordering

Beyond drilling, check three points: rim diameter (406, 451 or 507), which must match your tyres; internal bed width, which governs the section you can fit and the rim tape you need; and the braking type. Spoke length then follows from the rim and hub pairing you settle on — a calculation to run before ordering your BMX spokes and choosing your BMX hubs.

Checks and service life

Check for buckle and hop at every service, and spoke tension after a heavy landing. On an alloy rim run with pads, watch the thickness of the braking track: a hollowed sidewall or a marked wear groove signals a risk of failure under pressure. On a carbon rim, any impact on the hook, any lifted fibre or any dull sound under flex calls for replacement.

The BMX RACING advice

Tell us your class, your braking system, your hubs and the tyre width you are aiming for: we confirm the diameter, width and drilling that suit, and we work out the spoke lengths for the build. Dispatched within 24 to 72 hours and you can spread the cost over 2 or 3 payments available.