Mini-Z Box Stock Rules
v1Summary of recent changes
Published from nimrc.club/classes.
Spec sheet
- Notes
- 1/28 Mini-Z, full power; four AAA (alkaline/NiMH/NiCd); wheelbase 90/94/98/102mm; 6T-9T pinion; no traction compound.
- Spec motor
- Kyosho MZ9P or MZ9E (modified 28SRA)
- Tire additive
- Banned
- Body
- Molded hard-shell body, max 180mm x 83mm, headlight covers required, no lexan
- Chassis
- Kyosho MR03S/MR03S2/MR03 RTR/MR04 RWD or Associated SR27 (RWD)
1.Who it’s for
Full-power RTR Mini-Z class (modified 28SRA). Specifications identical to Rookie 50%.
2.Chassis
Kyosho MR03S, MR03S2, MR03 RTR, MR04 RWD, or Associated SR27 (RWD only) — must remain stock. Wheelbase 90, 94, 98, or 102mm only.
3.Motor & ESC
Kyosho MZ9P or MZ9E from the RTR. Max 20-gauge wire; safety switch may be removed; no other modifications.
4.Gearing
6T–9T pinion. Stock Kyosho gear diff only.
5.Wheels & tires
Any 1/28 production wheels — front max 8.5mm wide, rear max 11mm, diameter 19–20mm. Tires max 25.5mm mounted diameter. NO traction compound, tire warmers, foam, silicone, urethane, or ethyl carbonate — clean with 70% alcohol or water only.
6.Batteries
Four AAA (alkaline, NiMH, or NiCd). One additional battery allowed for the transponder.
7.Electronics
Stock RTR radio only (NIMRC exception: aftermarket radios allowed). No modifications.
8.Body
Any molded hard-shell body fitting the allowed wheelbase — max 180mm long × 83mm wide. Original headlight covers required. Lexan prohibited.
9.Option parts
Bearings, wheel nuts, springs, and T-plates from any manufacturer; original Kyosho suspension parts only. No tungsten or brass weight additions. King-pin flip permitted if the lower pin is shortened to prevent track damage.