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Wheel Categories

Track/Jam/Speed – Wide track and tall (62mm) indoor hardness 90A to 98A.

Art- Narrow width (57mm freestyle and 62mm dance and figures) Hard 96A – 101A

Rhythm – narrow width (52mm, 57mm 62mm) Very Hard 101A

Outdoor – Narrow and tall (62mm and 65mm) Soft 78A to 88A


Most wheels are made from urethane. Urethane was developed in the 20th century as a replacement for rubber due to shortages during the world wars. Petroleum was readily available and chemicals produced from oil were used to produce several plastics and then urethane. Urethane was first introduced as a wheel for skating via the skateboard wheels in the 60’s replacing wooden, hard rubber or clay wheels that would “chunk” or slide out from under even the lightest skateboarder. The first urethane wheels for roller skates were used for outdoor skating and then harder formulas were produced for top end speed skaters and indoor artistic skaters. Today there are several different methods of processing urethane for roller skate wheels and literally thousands of formulas to produce many different varieties or properties.


Wheels are measured in millimeters and marked with a “MM” notation. The smaller the MM numbers the smaller the circumference of the wheel. Smaller wheels (52mm) are used for rhythm skaters and for juvenile skates. Standard wheels (57MM) are used for most traditional skates and artistic skates. Tall wheels (62mm) are used for track skating, jam skating and speed skating. Oversized wheels (70mm) are specific to some track skating. Wheel size used is determined category and by skater preference.


Wheel hardness is determined by a “A” scale rating. The higher the number the harder the wheel. Softer wheels are used for outdoor skating (78A or 84A) Outdoor wheels are softer to provide a better rebound for skating on uneven surfaces. Rebound allows for the wheel to “roll” over the uneven surfaces rather that bouncing over them like the harder wheels. Hard wheels (90A to 101A) are used for indoor skating with the softer indoor wheels offering a better grip than the harder indoor wheels.


Soft wheels below 84A need a hub to reinforce the bearing seat in the wheel. Under normal conditions an 84A wheel will hold the bearings but not under extreme conditions. Hubs are used on harder wheels only to lower the weight of larger wheels. Usually nylon or aluminum hubs are much lighter than the urethane they replace. Metal hubs are preferred over nylon hubs to produce a much stiffer wheel and provide a better feel to the top end skaters. Nylon hubs tend to flex while skating.


Narrow wheels are standard with juvenile skates, artistic skate’s outdoor skates and most rhythm skates. The narrow shape makes the wheels lighter and much easier to maneuver when skating. Wide track wheels are used for most jam skates, track skates and speed skates because the wider surface provides more grip when cornering especially at high speeds.


Wheels are offered in an endless array of colors however different urethanes will produce different colors or hues due to the originals or natural color of the chemicals. Wheels are cast with powdered pigments to change the urethane color. Wheel color helps the skater know what hardness or grip the wheel is and allows the skater to have a different look.

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