VehiclesArrma Kraton 6S EXB
Arrma Kraton 6S EXB
1/8 scale · monster truck · ARA8708V6T1
- Top speed
- 67mphcalculated
- Final drive
- 13.44:1
- Tire
- 169mm
Open in Top Speedcommunity
Specifications
Last modified
| Spec | Value | Basis |
|---|---|---|
| Drivetrain | ||
| Pinion | 16TStock | Stock |
| Spur | 50TStock | Stock |
| Transmission & axle | 4.30:1Stock | Stock |
| Spur ÷ pinion | 3.125:1Calculated | Calculated |
| Final drive | 13.44:1Stock | Stock |
| Wheels & tires | ||
| Tire diameter | 169mmEstimated | Estimated |
| Rollout | 39.5mm per motor turnCalculated | Calculated |
| Power | ||
| Motor | 2050KVStock | Stock |
| Battery | Up to 6SLiPoStock | Stock |
| Performance | ||
| Theoretical top speed | 67.0mph on 6SCalculated | Calculated |
| Motor speed | 45,510rpm, no loadCalculated | Calculated |
| Advertised top speed | 65mphMaker's claim | Maker's claim |
| Vehicle | ||
| Part number | ARA8708V6T1 | |
| Scale | 1/8 | |
| Class | Monster truck | |
Stock is as the vehicle ships. Calculated is worked from the stock figures on this page rather than stored beside them, so the two cannot drift apart. The top speed is kinematic: an ideal no-load RPM with no slip and no loss under load, so a real car is slower. The maker advertises 65 mph, which is their own claim on their own conditions.
How these numbers were settled
The current EXB is an RTR, not a roller: Arrma's ARA8708V6 page lists the Spektrum Firma 4074 2050Kv motor and the Firma 150A Smart V2 ESC (4S/6S), so KV and cell count are real figures.
- The same Arrma page prints the 16T pinion and 50T spur; both are manufacturer-published.
- The 4.3 transmission and axle ratio is community-sourced: Arrma publishes no gear ratio anywhere, so it is the 43T ring / 10T diff input gear of the 6S platform (43/10 = 4.30), stated in an arrmaforum gearing thread and corroborated by the Arrma diff part numbers ARA310979 (10T main input gear) and ARA310990 (43T ring) that the parts trade lists as fitting Kraton/Talion/Typhon/Notorious/Outcast 6S.
- The final drive is calculated: 50/16 x 4.3 = 13.4375, rounded to 13.44.
- The tire diameter is also community-sourced and estimated, not confirmed by Arrma: 169mm (6.5 in) for the stock 3.8 dBoots Copperhead 2 comes from a member measurement in the arrmaforum tire-size thread.
- Cross-check: 2050Kv x 22.2V = 45,510 rpm, / 13.44 = 3386 wheel rpm, x pi x 0.169 m = 29.96 m/s = 67 mph, against Arrma's own '65+ mph' claim.
- The gearing, the tire and the marketing number all agree, which is the main support for the 4.3.
Sources
- ARA8708V6arrma-rc.com (opens in a new tab)
- calculating-motor-pinion-si…arrmaforum.com (opens in a new tab)
- kraton-6s-tire-size.41488arrmaforum.com (opens in a new tab)
Every figure on this page traces to one of these. Where they disagreed, the note above says which was used and why.