To install copy "bati.yft", "bati_hi.yft" and "bati.ytd" with openIV into "x64e.rpf/levels/gta5/vehicles.rpf".

or

I made a tool to make bike as AddOn here:
https://it.gta5-mods.com/tools/bike-addon-maker-alpha

Sorry about poor front wheel rotation, im still trying to figure it out how to setup it properly

--------
Models unlocked feel free to edit