BMX tires tend to be chunky, knobby and wider than road bike tires. They need to withstand punishment, similar to mountain bike tires. Yet unlike mountain bikers, BMX riders don't usually do much serious off-road work. Dirt BMX tracks are hard and not covered in roots and rocks. Flatland BMX bike tires are designed for stability and performing tricks on level, clean ground. Jump tires are wide and rugged for extra grip and balance.
For All BMX Bikes
Measure your wheel and frame size. BMX bikes come in four main sizes: mini, junior, expert and pro. If you're over age 12, you probably have a pro model. Pro wheels are 20 inches in diameter.
Select the type of BMX riding you're interested in -- flatland/freestyle, jump riding or track racing. This will influence the type of tire you'll need.
Ask the bike store attendant for the preferred style of tire that fits your wheel diameter.
Flatland and Freestyle BMX
Buy tires about 2.125 inches wide if you're a freestyle or flatland rider with a pro-size bike. The wider tires give you more balance and control. Ask for tires about 1.75 inches for expert freestyle frame sizes, 1.3 inches for junior and 1.1 inches wide for mini frames. These are the standard sizes for the mini and junior frames.
Purchase a tire with a smoother, slicker tread without deep, knobby grooves if you do mainly flatland riding on concrete.
Feel the tread. Look for a little more grip if you do most of your freestyle riding in parkland or on demanding urban tracks. The extra grip will help you maintain control.
Look for the tire's recommended PSI, a measure of pressure. This is usually written on the side of the tire wall. Buy tires between 40 and 70 PSI for freestyle riding for a more cushioned ride, according to Vital BMX. Choose higher PSI if you prefer spin-style tricks.
Choose thinner tires than freestyle tires if you're a jump BMX rider. Aim for between 1.9 and 2 inches for a pro-style frame, and about 1.6 inches for expert models.
Run your finger along the tire tread. It should feel knobby and deep. You need the deepest treads for dirt jumping to hold the terrain closely when you land.
Pick tires with a PSI limit of between 40 and 70. This helps make for a softer landing.
Hard Dirt-Track Racing
Buy thin tires for racing BMX bikes -- about 1.75 inches for pro frames and 1.5 inches for expert models. Junior and pro models usually have standard tire widths.
Find treads with grip, but no deep, knobby grooves. You need traction without resistance to keep up your speed.
Pick a tire that can handle over 100 PSI if you're a race rider looking for speed. Highly pressurized tires help your bike travel quicker.
Ask the bike store attendant for a trial ride on a BMX with tires similar to the ones you want. This is the best way to get a feel for the tire.
Don't use flatland tires for dirt-track riding. You could skid or slip.