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@hippy
^ I'm calling bullshit on that 1930s bike. They must've measured a bike built at size 24cm or only counted the main triangle or something. The ALU saddle and post weighs half the entire STEEL frame? I don't think so.
1000g
"I'm going to kick off with my personal highlight of the show: Reynolds' new 953 stainless steel tubing, as built into a frame by Melbourne's Baum Cycles. Like just about every British rider my age (late 30's, thanks for asking) my first decent bike was made from Reynolds 531 steel, so I have a soft spot for the Birmingham, England tube maker.
However, the rush to build lighter and lighter frames has left steel behind in recent years. Aluminium and then carbon fiber have been the materials of choice for riders seeking a very light frame. Reynolds launched its 953 tubing just a couple of weeks ago and if it delivers on its promise it will put steel back in consideration. At the Bicycling Australia show, Baum had on display what the company's Jo Banks believes is one of just three 953 frames in the world at the moment (the other two tubesets went to Boston, USA builder Independent Fabrications). The weight: 1000g.
Baum's Jo Banks told Cyclingnews that this prototype frame was built to the exact same dimensions as "a well-known titanium company's 800g frame." In other words, this is a weight for a smallish 'medium' sloping frame.
By any measure, a 1000g steel frame is a jaw-dropping achievement. What's made it possible is the extremely high strength of this new material, which Reynolds describes as a "maraging stainless steel, specially manufactured for Reynolds by Carpenter SpecialtyAlloys, USA". 'Maraging' is a hardening and strengthening treatment applied to a class of high-nickel steels. After it's been treated, the ultimate tensile strength of 953 is 1750 to 2050MPa, depending on exactly how long it spends in the over and at what temperature. The strongest steels in widespread use before 953 - air-hardening steels such as Reynolds own 853 - had ultimate tensile strengths of 1200-1400 MPa,while good grades of regular chromoly run 900-1000MPa. A stronger material means you can use less of it, of course, and 953 has tube walls as thin as 0.3mm.
Reynolds admits it's not a frame design company - it makes tubes. It's therefore working with companies such as Baum, and Independent Fabrication to fine-tune the tube design of the 953 set. The advantage of the new material, according to Banks, will not be "stiffness or weight but strength. All steel is the same weight and stiffness but this is twice as strong." That will allow builders like Baum to make ultra-light steel frames that are still durable. As 953 is a stainless steel it will also have the advantage of being corrosion-resistant and being able to dispense with the paint.
Banks estimates that a Baum frame in Reynolds 953 will cost about AU$4,000, which is comparable with the company's plain gauge titanium frames - but lighter.