Seth Rosko builds steel frames quietly in Brooklyn with little fan-fare or publicity. As a bike builder, he draws on his experience racing and fabricating vintage motorcycles, and his many years of work under the Brooklyn Machine Works (known for their Gangsta Track, DH and park bikes) banner. Since setting off on his own, Seth seems eager to challenge himself with designing frames to fit the individual rider, from road to BMX bikes. His background serves him well as he succeeds in achieving understated form driven by function, frames speak in pure, purposeful designs for aggressive riding and racing. There are no hand-carved lugs, no polished head-badges, just precisely machined bits from Paragon Machine Works, thoughtfully affixed to quality tubes, in this case Columbus tubes adorned with glittery Granny-Smith green.
Made-in-the-USA Chris King, Thomson, Zanconato, and Parlee components make a bike that its owner calls “Practical Fancy.” The rims are alloy, the brakes are cantilever in spite of the looming disc-for-cyclocross hype, the Challenge tires are glued on, and the ceramic bottom bracket is of the Pressfit 30 variety, to combine the old and new school. The fork’s provenance is, according to the builder, top secret.
The beauty of purchasing a frame from a quality local custom builder is the inherently collaborative design process. In this case, Seth’s long MTB/BMX building experience and Brett’s (the customer) urgent need to dote on details like bottom bracket drop, trail measurement and chainstay taper. With Seth’s execution and precise welding, Brett received, according to him, “the most balanced riding, confidence inspiring bike I’ve ever owned”. And green means “GO.”