Mini 4WD Race Classes: Stock, B-MAX and Open
Stock Class, B-MAX and Open are not the same rulebook. How official Tamiya events, Basic-MAX GP v5 and local Malaysian shop races actually differ on race day.
Welcome to Monkee Mods
We’ll remember your pick and take you straight there next time.
Click to zoom
Out Of Stock
This product is currently unavailable.
Browse available alternativesA 19mm aluminum ball-race guide roller from Tamiya's High Grade (HG) roller line, built in the "ringless" style — the aluminum roller body itself forms the running surface, without the separate plastic sleeve or ring used on some ball-race rollers. This particular release is a limited version tied to Tamiya's Asia Challenge Mini 4WD tournament series, distinguished from the standard retail roller by its green-printed Tamiya logo.
At 19mm, this sits among the larger-diameter rollers in Tamiya's HG range — bigger than the widely used 13mm and 17mm sizes — which racers favour on faster courses because a larger roller contacts a course fence over a gentler curve and holds a steadier line than a small-diameter roller bouncing along the same fence. Being a ball-race design rather than a plain bushing, it rolls with noticeably less drag than the plastic rollers in most Tamiya kits, which is why aluminum ball-race rollers are among the most common first upgrades a racer makes. The green logo print is purely cosmetic and doesn't change the roller's dimensions or bearing spec versus the standard-graphics version.
Stock Class, B-MAX and Open are not the same rulebook. How official Tamiya events, Basic-MAX GP v5 and local Malaysian shop races actually differ on race day.
What scale is Mini 4WD? Learn the 1:32 format, typical car dimensions and official race measurements to check before modifying your car at the bench.
Building the best Tamiya Mini 4WD setup means matching the track, not chasing peak speed. Roller layout, braking, mass and a baseline you can repeat.