Bias-ply (diagonal) and radial motorcycle tires differ primarily in carcass construction: bias tires feature crisscross diagonal plies (30-40° angles) creating stiffer sidewalls, while radials feature parallel, 90-degree ply cords. Bias tires excel in heavy-duty, off-road applications and comfort at low speeds, whereas radials offer superior comfort, lower rolling resistance, and better stability at high speeds.
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