DUOTONE FOIL ASSIST — Full Breakdown with Cyril Coste

In this exclusive FOILERS Podcast episode, Pete sits down with Cyril Coste, the lead designer behind the all-new Duotone Foil Assist. Cyril shares the complete inside story — from early prototypes and battery decisions to mast design, remote controls, safety systems, and real-world riding performance. Cyril’s background spans pro kiteboarding in France, R&D roles in Maui, founding Takuma and its e-foil program, and now leading Duotone’s assist project from Japan. With R&D testing across Japan, Taiwan and China, this is the most detailed insight yet into how Duotone built their new foil assist system. What we cover in this episode: • Why Duotone chose a waist-mounted battery harness • How the free-hand remote works (7 speeds, boost mode, safety stop) • Power output, thrust, blade options (plastic, aluminium, 3-blade) • Runtime expectations • Why high-voltage HV LiPo batteries give long, consistent power • Safety: auto-stop, waterproofing, crash behaviour & floatation • The philosophy: lightweight, minimal, “no weight on the board” • Why Cyril rides small foils (500–600) with assist • Midfish board design — mid-length, thin profile, fish tail, cable channel • Aluminium vs D-Lab carbon masts & full motor integration • Modularity: swapping between assist & cruise (e-foil style) in 2 minutes • Adapters for other foil brands & Armstrong fuselage compatibility • Maintenance tips: battery storage mode, rinsing, quick-charge workflow • Safety guard design for the Cruise mast • Ideal users: downwinders, proners, wave riders, wing learners, flat-water beginners • Teaching with assist — instructors remotely controlling take-off • How assist enables bigger waves, upwind runs & long downwind sessions • Global release timing, distribution & first availability in Australia Why this system is different Cyril explains why Duotone went for a high-voltage, lightweight, modular approach — prioritising freedom, sensitivity, and a “true foil feeling.” No weight on the board, fast blade response, powerful but controlled acceleration, and the ability to ride smaller foils and thinner boards without compromise. Quick Fire Questions: • Dream foil destination (Tahiti) • Underrated skill (mast placement & board position) • One word to describe foiling (Freedom) • Best foiling advice Cyril ever got • What he wants riders to say after trying the Duotone Foil Assist If you want the most complete breakdown of the Duotone Foil Assist — straight from the person who built it — this is the episode to watch.