Mini 4WD PRO 13mm Roller Upgrade with Ball Bearings for Super-II compatibility - Tamiya 15551 Jr  [15551]

Slim 13mm POM rollers built for smooth spin

Tamiya's 13mm plastic rollers are presented as a compact option for advanced Mini 4WD builders who regularly run multi-lane tracks. The assembly combines a larger POM plastic outer section (blue) wrapped around a bearing core, with aluminum inserts to secure the bearings in place. This configuration aims to reduce rotating mass while retaining free rotation under load.

Compared to older 13mm plastic-ring rollers, this set enlarges the plastic area while keeping metal inserts for bearing retention. The manufacturer points to weight savings versus some aluminum ringless types, making these rollers a lighter alternative where chassis balance and reduced rotational inertia are priorities. The kit contains two rollers and the necessary screws, and it is compatible with Mini 4WD PRO and standard Mini 4WD cars.

These rollers are suitable for track formats where 13mm rollers are common, such as three-lane and five-lane layouts. The POM surface reduces friction at lane contacts, and ball bearings lower internal resistance compared with plain plastic bushings. The aluminum holders aim to keep bearings seated during impacts or sustained running.

In summary, these rollers give builders a bearing-equipped, lightweight plastic 13mm option for multi-lane racing; effectiveness will vary with individual car setup and circuit profile.