Never really built a gearbox before but knew the basics of a 2 and 4 speed boxes so i smashed them together and build this kinda small 8 speed gearbox : r/legotechnic
gearbox – Nico71's Technic Creations
George Staples' Lego Technic TRANSMISSION Tutorial - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums
Pro Instructions - LEGO 5 Speed + Reverse Manual Gearbox – Green Gecko Workshop
Pro Instructions - LEGO 5 Speed + Reverse Manual Gearbox – Green Gecko Workshop
LEGO MOC 2 Speed Gearbox by thatbrickguy | Rebrickable - Build with LEGO