Seth Rosko’s 650b Single Speed MTB

The problem with going to New York City is that I spend more time photographing bikes, then I do actually riding them. Which, in this most recent trip, wasn’t as much as I’d like. Being behind a lens, staring down a unique beaut like this does have its merits. Especially when you’re so familiar with its builder and owner.

Seth Rosko was one of the first builders in Brooklyn that I spent a good amount of time profiling years back. We first met at Brooklyn Machine Works, where he was a designer and fabricator. He and Joe worked extensively on the Gangsta track back in the day, before setting out on his own.

Rosko builds unique, yet utilitarian, yet lightweight bicycles made for racing. Each year, more and more fledgling racers find themselves on a Rosko and that means that Seth has less and less time to work on his own bikes. Case in point: this 650B single speed MTB. It took Seth years to finish this bike but he managed to complete it in time for this year’s season.

Using the ultralight True Temper Supertherm tubing, Black Cat dropouts and Stan’s tubeless wheels, this thing is light. It comes in at 20 lbs with XT pedals.

  • Wade Stevens

    you know I like that fork. should call it Yo Rosko.

  • Adam Valdez

    Niner bottle on a 650b build! Shenanigans!!

    • Doug M.

      Promo bottle for singlespeedapalooza 2013.

  • Lee Murai

    Great looking build and nice photos too. I just finished building up a singlespeed (26″ converted to 650B) MTB in a similar style.
    Bontrager Race Lite frame and custom supercrown fork from Hunter Cycles.[email protected]/9258505729/[email protected]/9261287260/

    • pszabo

      chain tension?

      • Lee Murai

        white industries ENO eccentric hub.

  • recurrecur

    lovely. just lovely.

  • Jamie McKeon

    Awesome shoot location too dude

  • Phat like a little red tractor. Love it, Seth!

  • kermitonwheels

    The silver ano post and bar are a nice (and surprising) touch on this build. That’s a no nonsense machine, love it.

  • btdubs

    This bike is sick…. Flat pedals! Badass. Nothing takes you back to feeling like a kid again like flats and single speed.

    I’d ditch those Stan’s decals though. and match the stem with the bars, dangit!

  • AttackCowboy

    Love those dropouts. This looks like a blast to ride. Any chances on getting Seths thoughts on riding 650B wheels?

  • smarjberg

    I think this might be the best-looking bicycle I have ever seen, with like zero exaggeration. Everything about it is so simple, clean and classically correct somehow, even though I don’t think I’ve ever seen a bike quite like it before. I’ve been looking at this page like daily since a week ago when I found it. Fantastic job.