Wheels & spokes

How it works

The wheels carry the tyres and transmit braking and acceleration forces. There are cast wheels (one-piece aluminium alloy, often tubeless) and spoked wheels, where the rim is linked to the hub by tensioned spokes, more common off-road, on adventure bikes and on classics. A rim must run true: hitting a pothole or kerb can bend or crack it, causing vibration, air loss on a tubeless tyre and danger. On a spoked wheel, spokes loosen over time: a loose spoke sounds dull when tapped, and the wheel goes out of true. Wheel bearings, in the hub, let the wheel turn: a worn bearing gives play in the wheel and a rumbling noise. The wheel and tyre are balanced with weights; a lost weight causes vibration at certain speeds.

Maintenance tips

• ✓Inspect the wheels after any hard impact: a crack, buckle or bent rim edge must be checked before riding.
• ✓On spoked wheels, check spoke tension regularly by tapping them lightly: a dull sound means a loose spoke.
• ✓Check for wheel play by rocking the wheel sideways with it lifted: there should be none.
• ✓Have the wheel balanced at every tyre change.
• ✓A cracked rim cannot be repaired: replace it.