The Hario Suiren is a specialty cone released by Hario that takes the V60 concept in the opposite direction of the Mugen: instead of slowing flow, it accelerates it. The ribs are taller and more pronounced than a standard V60, the filter barely contacts the wall, and the result is one of the fastest-draining cones Hario has ever made.
Fast flow is not universally good. The Suiren rewards brewers who already have pour technique because it punishes pauses and uneven stream speeds with under-extraction and bypass. Done well, the cup is startlingly bright, floral, and articulate — the kind of V60 profile light-roast specialty cafés chase. Done casually, it tastes watery.
A starting recipe: 15 g of coffee to 250 g of water (1:16), a grind one notch finer than your standard V60 setting, water at 94–96 °C, three to four continuous pours in 2:00 to 2:45. Uses V60 02 paper filters. The Suiren is the Hario for an experienced brewer with light-roast beans and a steady hand on the kettle.