Ringless 19mm Ball Race Roller M4WD-40/LB for tuning by 3Racing  [M4WD-40/LB]

3Racing M4WD-40/LB 19mm ringless aluminium roller technical notes

The 3Racing M4WD-40/LB is a 19mm ringless aluminium ball race roller in light blue intended as a compact replacement component for Mini 4WD chassis. Use it where reduced outer diameter and altered contact geometry are required for tighter guide interactions.

For setup precision, verify post diameter, seating depth and lateral clearance prior to installation. Adjust spacer stacks incrementally to control axial play; confirm the roller runs without binding and with minimal lateral slop under typical track loads.

When integrating on MA, MS, AR, FM-A, VS or Super-II style platforms, review protector and guard positions. The ringless outer face requires consideration of how the roller contacts bumpers and guide rails, so adapt mounting positions to preserve intended line and stability.

Inspect packaging and part labelling on delivery and confirm finish and quantity before adding to a competition or development setup.