Tyres

BMX tyres are the rubber tyres that fit 20 inch wheels. Freestyle sizes usually run from 2.1 to 2.5 inches wide. They are the only part of the bike that touches the ground, so choice of tyre changes grip, speed and comfort.

What it does

The tyre grips the ground, absorbs hits and holds air. On a BMX it also protects the rim from impacts. The tread pattern, rubber compound, width and pressure all change how the bike feels.

A tyre fits a rim with a matching bead seat diameter. Twenty inch BMX tyres fit a 406mm bead seat. See rims.

Types and standards

Width

Tyre size is written as diameter by width, for example 20 x 2.3. The first number is the wheel size in inches. The second is the width of the tyre in inches.

Width	Typical use
2.0 to 2.1	Light and quick. Common on race and some park bikes.
2.2 to 2.3	A good all-round middle.
2.4 to 2.5	More grip and cushion. Popular for street and dirt.

Pressure ranges

These are rough guides only. Always check the sidewall for the maximum and minimum, and adjust to your weight and taste.

Discipline	Rough range
Street	About 60 to 100 PSI
Park	About 60 to 100 PSI
Dirt and trails	About 40 to 65 PSI

Many 20 inch tyres are rated to 100 PSI and some low-pressure versions only to 65 PSI, so the sidewall always wins.

Higher pressure rolls faster and resists pinch flats on hard landings. Lower pressure gives more grip and a softer ride. See BMX tyre pressure for more detail.

Tread patterns

Pattern	Notes
Slick	Smooth tread. Fast and quiet on concrete. Little grip on dirt.
Semi-slick	A smooth centre with small knobs on the shoulders. Good for park and street.
Knobby	Large lugs. Best on dirt, loose surfaces and trails.

Many street and park riders prefer slick or semi-slick treads. Dirt riders favour more tread.

Wire bead or folding bead

Bead	Notes
Wire	A steel wire in the bead. Stiffer, a bit heavier, lower cost.
Folding	A flexible fibre bead (often Kevlar). Lighter and can be folded for storage or travel.

Dual compound

A dual compound tyre uses two rubber mixes. A harder rubber is usually used down the centre for longer wear, and a softer rubber on the shoulders for grip when leaning. Single compound tyres are simpler and often cheaper.

Sizing and compatibility

1. Wheel size: match the tyre to the rim bead seat. A 20 inch rim takes a 20 inch (406mm) tyre.
2. Width: check the rim maker's recommended tyre width range. A very wide tyre on a narrow rim can feel unstable.
3. Frame and fork clearance: make sure the frame and forks have enough room for the tyre, with some gap for mud and wheel flex.
4. Tube size: the tube must match the tyre size and valve type.

Other wheel sizes

Some riders and bikes use bigger wheels. A 22 inch wheel has a 457mm bead seat. A 24 inch wheel has a 507mm bead seat. These tyres are not interchangeable with a 20 inch rim, even if the width is the same.

How to choose

1. Decide on width first. Most riders end up between 2.2 and 2.4.
2. Choose the tread for your surface. Slick or semi-slick for concrete and park, knobby for dirt.
3. Pick wire bead unless you want the weight saving.
4. For a first set, a sturdy mid-priced tyre is a better buy than the cheapest. Tyres range from low to moderate prices, and premium folding or dual compound tyres cost more.
5. Check your bike's clearance before going to a wider tyre.

Maintenance

• Check pressure with a gauge before each session. Tyres lose air slowly.
• Look for cuts, bulges and cracked sidewalls. Replace the tyre if the casing shows through.
• Replace tyres with a flat worn spot. Street riders who skid can wear out a rear tyre quickly.
• Check the inner tube and rim tape if you get repeated flats.
• Rotate or swap front and rear tyres to even out wear.
• See BMX maintenance basics.

Related parts

Rims, front hub, cassette hub, forks and brakes.