Most motorcycle mods come as .wft (model) and .wtd (texture) files that replace an existing bike in the game. GTA IV - How To Install Vehicle Mods [EASY WAY]
: Another long-standing source with a dedicated bikes category. 2. How to Install (Manual Method)
: Widely recommended for its massive collection of vehicles for all GTA versions. Nexus Mods : Good for high-quality, verified modifications.