Custom Works Foam Pre-Mounted Dirt Oval Rear Tires are available in a variety of compounds, allowing you to find the best setup possible for your track conditions. These tires are premounted on standard Custom Works 2.0" wheels.
X series soft X2 and medium X3 compound foam are the most versatile in the Custom Works lineup. X2 will often have more grip than other options. Custom Works recommends the use of a firmer compound if the track is abrasive, or to get the car unstuck in slower spec classes like 17.5.
R series is a slightly different blend than the X serie, and is available in soft R2, medium R3 and firm R4 compounds. R2 is sometimes better than X2 on very wet clay, and it other scenarios can be used to unstick the car in spec classes. Custom Works recommends the use of a firmer compound if the track is abrasive, or to get the car to roll more freely in slower spec classes like 17.5.