135mm Chain Drive Drum 56mm 50.8mm Brake Lock Hub

LG-N7003-2G is the drum brake lock version of the A02 automatic 2-speed internal gear hub. Its main value is the combination of mechanical self-shifting and drum brake lock matching, making it a practical option for low-maintenance city bicycles, public-use e-bikes and urban mobility platforms that require a protected rear hub brake layout.

Compared with the disc brake versions, this model uses a 135 mm O.L.D. structure, 56 mm G1 chainline, 50.8 mm G2 chainline and 30.8 mm brake mounting width. These differences should be checked carefully during frame and brake system matching.

• Automatic 2-speed shifting reduces rider operation during daily city riding.
• 133% total gear range supports easier starting and efficient cruising.
• Sealed internal gear structure helps protect transmission parts from dust, mud and rainwater.
• Chain Drive System configuration for the target drivetrain layout.
• Drum Brake Lock matching for the selected rear brake structure.
• 135 mm O.L.D. rear hub structure for frame matching.
• IPX6 waterproof rating and RoHS / REACH certification support international product planning.

The A02 series uses a mechanical automatic shifting structure based on CentriGear shifting logic. As riding speed changes, the internal mechanism shifts between the 1.00 and 1.33 ratios without a handlebar shifter. This gives daily riders a simpler experience, while helping OEM brands create a cleaner rear drivetrain layout with fewer exposed shifting components.

This model is best used for city e-bikes and low-maintenance bicycle platforms requiring integrated drum brake lock matching. It is especially relevant for OEM projects where the buyer wants a lower-maintenance alternative to exposed external shifting, but still needs the hub to match a specific brake interface, dropout width and drivetrain line.

Before sampling, OEM customers should provide frame drawings, rear dropout spacing, brake type, wheel size, spoke requirements, chainline or belt-line target, axle compatibility and expected use scenario. Lofandi can support model selection, drawing confirmation, sample preparation and installation matching according to the final vehicle platform.