The flat-1 is the ultimate urban mini velo frameset. Designed for the streets of japan, this frame was born out of the need for a compact bike on narrow streets and to store at home.
Available in one adult size, this single speed/fixed gear format frameset accepts 20 x 1 3/8 or 20 x 1.75 wheels (406 or 451 etrto) meaning the brake drop will alter depending on the wheel size used. Example – when using a 20 x 1 3/8 wheel size we recommended using our brs 101 brakes which have a drop of 43-57mm.
We these framesets its important to think about gearing when selecting components for the build, due to the small wheel size a larger gearing should be considered to give a ‘normal’ gear ratio (i.E if running a 16t freewheel, then the chainring will probably want to be circa 50t+)
geometry
- head angle 73 deg
- top tube 529mm
- seat tube 460mm
- chainstay 380mm
- bb to fork 572mm
- rear dropout 120mmx10mm
- axle to brake 280mm
specifications
- material tig welded 4130 cr-mo
- headset compatibility threadless 1 1/8"
- seatpost 27.2mm
- seat clamp 31.8mm
- max tyre clearance 451 = 40mm
- bottom bracket bsa threaded 68mm