1/10th 2WD 13.5 Stock Class Rules (Wales)
Based on BRCA & ROAR Stock Regulations
1. Overview
This class is intended to provide a level, competitive environment using affordable, readily available 13.5-turn brushless motors and 2WD buggies. It encourages close racing based on driving ability and setup skill rather than motor tuning or electronics advantage.
All cars must comply with the current BRCA 1/10th Electric Off-Road Rules except where modified below to incorporate ROAR Stock Class principles.
2. Vehicle Eligibility
- Vehicles must be 1/10 scale, 2-wheel drive electric off-road buggies.
- Drivetrain must be single motor, single speed.
- Car must visually resemble a 1/10 off-road buggy — no truck or short-course conversions.
- Cars may be inspected or weighed at any time during the event.
3. Motor Regulations
- Only 13.5-turn (13.5T) sensored brushless motors permitted.
- Motor must appear on the current BRCA Approved Motor List.
- No internal modifications (rotor, stator, or sensor board changes) beyond manufacturer specification.
- Any end-bell timing adjustment must be visible and within motor approval range.
- Cooling fans are allowed but must be powered from the receiver or ESC supply (≤ 6 V).
4. ESC Regulations
- ESC must be BRCA approved and configured in Zero-Timing / “Blinky” mode.
- Boost, Turbo, Dynamic Timing, or any electronic advance features are strictly prohibited.
- The LED or display must clearly indicate “Blinky” status when inspected.
- Use of unapproved firmware or modified ESC software is not permitted.
5. Battery Regulations
- Only 2-cell (2S) LiPo or 2-cell Li-HV (7.6 V nominal) batteries permitted.
- Batteries must be hard-cased and appear on the current BRCA Approved Battery List.
- Maximum charge voltage: 8.40 V total (4.20 V per cell).
- Maximum charging rate: 10 A or 2 × battery capacity (whichever is lower).
- Batteries must be charged in a LiPo-safe bag or container designed for this purpose.
- Pre-warming, heating, or externally raising battery temperature above ambient (25 °C) is prohibited.
- Charging at over-rated amperage is not allowed.
- Race organisers may carry out temperature checks or spot-voltage inspections prior to heats or finals.
6. Weight & Dimensions
| Specification | Requirement |
|---|---|
| Minimum Weight | 1,474 g (race-ready, including transponder and body) |
| Maximum Width | 250 mm (as per BRCA 1/10th rulebook) |
| Wheelbase | Within manufacturer spec for model |
| Ride Height | No limits |
7. Tyres, Wheels & Body
- Tyres: Any commercially available 1/10th off-road rubber tyre may be used unless a control tyre is specified.
- Additives: Only non-solvent, water-based traction compounds permitted.
- Wheels: Must match 1/10th 2WD buggy size (e.g., 2.2” or 61 mm).
- Body: Buggy-style shell covering all major components. No truck or short-course bodies permitted.
8. Transponder & Timing
- Racers must ensure transponders are securely fitted and functional, it is the racers responsibility to ensure their transponder is operational.
9. Technical & Conduct Regulations
- Cars may be checked at any time for compliance (weight, voltage, firmware, temperature).
- Drivers must behave in a sportsmanlike manner and marshal as required.
- Race Director’s decision on legality or conduct is final.
- Repeated technical infringements may result in disqualification or suspension.
10. Rule Hierarchy & Supplementary Regulations
- Primary Reference: BRCA 1/10th Electric Off-Road Handbook (2025).
- Secondary Reference: ROAR Electric Off-Road Section — Stock/Spec Class rules.
- Local clubs or events may issue Supplementary Rules to define control tyres, gear ratios, or format specifics.
- Any rule not covered here reverts to the BRCA handbook guidance.
11. Summary of Key “Stock” Intentions
| Area | Limitation | Purpose |
|---|---|---|
| Motor | 13.5T only | Creates parity and cost control |
| ESC | Blinky/Zero Timing | Prevents software timing advantage |
| Battery | 2S, 8.4 V max | Maintains safety and fairness |
| Weight | ≥ 1474 g | Ensures stability and realism |
| Tyres | Open (rubber only) | Allows setup variety per surface |
| Additives | Not allowed | Club Rules for longevity of track surface |
| Charging | ≤ 10 A, no pre-heating | Safety & longevity of cells |