29er frame.

My new 29er, with short chainstays that require a bent seat-tube. The short chainstays transform the handling of a 29er: easier to loft the front wheel and lift the rear wheel, with all the smooth-rolling benefits of a 29er in rough terrain. The chainstays of 29er can only be so short if a straight seat-tube is used. With this design I have managed to achieve the 430mm 16.9" chainstay length that works so well on mountainbikes and still use a lightweight steel seat-tube.

I've set into the usual thinwall seat-tube a thicker-wall section that's only 40mm long with a neat, angled, welded joint. The thicker-wall material gives durability with only minimal extra weight. This approach is necessary because you simply can't bend or shape the standard seat-tube with its ultra-thin wall thickness of only 0.6mm. My method is also easier than inserting a short, curved lower section of seat-tube. Mass-produced frames with curved 1-piece seat-tubes use lower-spec, thicker-walled tubing.

Frames of this design will have either vertical dropouts or a swinger-style adjustable rear dropout for singlespeed duty. The rear-entry dropouts were used in this case since main purpose of the frame was to to prove this new design.

This bike proved itself on the awesome Redwoods trails in Rotorua. When the aim is to flow through twisting, winding trails, a 29er is what you want. There's nothing better than effortlessly riding through a rough section, and this is what this type of bike excels at.

One of my 29er frames can also be supplied with the new Direct Mount front derailleur boss, made by Paragon Machineworks which is the most recent design, optimized for maximum tyre clearance. Even with chainstays as short as 430mm this frame can run a Shimano XT front derailleur without it contacting the tyre..

This frame also has 'S and S' frame couplers, which enable to the frame to be packed smaller for air-travel. The couplers will actually make the frame slightly stiffer, and are stronger than the bit of tube they replace. More on the couplers here.

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