Arrma Limitless

The Arrma Limitless is a speed-run car: a 1/7 scale 8S machine built for straight-line speed on a smooth surface. With the right gearing and a long enough surface, it can pass 100mph.

What speed running involves

You need a long, smooth, empty surface such as an airfield, a closed road or a large empty car park. A radar gun is useful if you want to record speeds, and you should plan for where the car goes if something breaks at speed. It is a different pursuit from bashing.

Gearing

The Limitless is supplied geared conservatively. Going faster means taller gearing, which puts more load on the motor and ESC, so temperatures need monitoring. Most people build up gradually rather than fitting the largest pinion straight away.

AVC stability control

AVC stability control is fitted as standard and is worth leaving on, as small steering corrections at these speeds happen faster than a person can make them.

Running costs

8S means two 4S packs and a matching charger. Tyres wear quickly at speed-run pace, and belted tyres are recommended above about 70mph.

For speed you can use day to day, the Infraction or Felony are street bashers rather than speed-run cars. Spares are stocked - see RC car spare parts.