Actually, Gary Klein's 'realization' is just simple engineering, apropos and employed by Renovo, Cannondale, Cervelo, Boeing and any other manufacturer who employs engineers and wants a torsionally stiff tubular section. The 'Renovo guys' have (actually calculated) and tested that they can easily equal the stiffness of a Cervelo S2 or Scott Elite carbon frame using a 2.5 diameter downtube (the Scott is 2.07). Your assertions about Renovo's frames are authoritative sounding, but altogether wrong. Sorry, Renovo doesn't do: "5' diameter tubes", "egg-crate tubing", "internal honeycomb", 'incredibly delicate bikes" or "sub-millimeter thicknesses walls" A millimeter = .039". Typical butted steel tubes are in the range of .04-.06mm or ~.020", carbon about the same. Renovo's wall thicknesses are substantially thicker and far more damage resistant. Try renovobikes.com for factual information, including comparative tests of our wood tubes against those of aluminum, steel and titanium. Ken Wheeler, Renovo Hardwood Bikes

Actually, bamboo is a grass, not wood at all, with far different properties. Bamboo is very fragile having an M&M-like makeup, a very thin, hard outer shell over a soft wall. Numerous bamboo bike producers have compounded that fragility by joining the tubes with rigid lugs of aluminum, steel and carbon. Calfee, who produces both bamboo and carbon bikes, learned through early failed bamboo frames that failure is guaranteed using a rigid connector with flexible tubes. He quickly switched to wrapped lugs whose modulus more closely matched the bamboo than the uber stiff carbon used first.Many latecomer bamboo bike makers copy Calfee's mistake. The book "Bicycles & Tricycles" by Archibald Sharp, Dover 1977, is a great engineering book first published in 1896 intended to educate the public (and hopefully) the thousands of garage bicycle 'manufacturers' who had no idea how to engineer a bike. There is usually a huge difference between a wood bike designed and built by engineers and a woodworker's project bike. Ken Wheeler Renovo Hardwood Bikes