We first caught a glimpse at Kuroshiro’s revolutionary Ensō685 415g carbon fat bike rim last winter. Last summer, the Italian company with a Japanese name followed suit with the introduction of the 50mm-wide Ensō950 rim, intended to shave grams from the small but growing number of 29+ mountain bikes. Now, Kuroshiro is releasing details of its latest carbon creation, the Ensō747, an extra-wide 27.5in rim for the 27.5+ market.
Like Kuroshiro’s previous wide and light carbon rims, the Ensō747 is produced by Italian composite specialist Alchemist Engineering. The Ensō747 has an external width of 45mm and an internal width of 38.6mm.
Claimed weight for the Ensō747 rim is 345g. The company claims that a complete wheelset built with light fat bike hubs, high tension spokes, alloy nipples and Ensō747 rims can be built at as light as 1,390g.
The Ensō747 rim uses the same construction technique as the Ensō950. It features a raised spine, called Alpha-Ridge, that crosses back and forth across the exterior of the rim, connecting the spoke holes. The rim uses a single-walled design with the exception of the alternating spoke channel, which uses a box section constructed around a polymer mold that helps to make the rim airtight without the need for tubeless tape, furthering weight savings.
The closed cell polymer molded into the rim boosts stiffness
The Ensō747 is still in the late stages of development. Production rims are expected to be available in limited quantities in late spring. The price per rim is expected to be €849. US, UK and Australian pricing TBD.
The 38.6mm internal width will change the shape of tyres. Tyres with a rounded profile may be better candidates than those with a squared-off profile
For more information visit www.raceware.com.