Specifically designed for use on mixed-wheel Ebikes, Reserve’s 30|HD 31|DH E-MX wheelset offers the perfect balance of stiffness, performance, durability and weight. Combining our 30|HD front wheel with our World Championship-proven 31|DH rear wheel, the larger 29 inch front wheel provides more traction and stability for more confidence, squaring off turns and diving for the inside lines with a 27.5-inch rear that delivers quick acceleration and pop to get the entire bike lofted into the air.