Gravel / Gravé / Gnarmac / Groad / ATB

Carbon -> Aluminium-> Steel -> Bamboo -> Magnesium -> -> Titanium

TBH, I'd buy a Kinesis G2 if I could find a frameset somewhere in Europe...

I've always doubted the "853 main tubes" claim being this heavy AND super flexible. Mine started shifting out of the saddle while bikepacking cause of the frameflex.

All steel basically has the same Young's Modulus. 853 is as stiff as boggo 4130.

And reynolds will custom draw tubes of different thicknesses for bigger brands that work with them. So it can be 853 but be way chonkier than the 853 your local framebuilder would get their hands on.
Niner, Genesis etc will be more concerned with failures and returns when they don't know their customer than one off builders who know exactly who they're building for.

Niner, Genesis etc will be more concerned with failures...

even OTP alu weight as much/heavier than custom build 853.

Also OTP bikes need to pass safety standards. I don’t think many builders get their bikes ISO tested, but I may be wrong?

Seeing some of the POS cheapo toy bikes with ISO stickers on, I'm not sure that counts for too much.

853 is as stiff as boggo 4130

Well, yes, given the same thicknesses and tube size.

Can nobody stick to the schedule around here?

Er.

Depends on carbon content.

We were talking about the likes of Niner and Genesis. Of course there's gonna be cheap shit out there, but in terms of brand name bikes there is at least a stamped certificate and not insignificant threat of a lawsuit to consider.

Nope, not enough for anyone riding a bike to notice. Reynolds list 207 GPa for all their steels from 520 up to 953

https://www.reynoldstechnology.biz/wp-content/uploads/2015/08/rtl_steel_alloys_extract.pdf

Bars need rotating down and moved up.

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Is stiffness not the more relevant figure for bicycle frames? The higher end tubes can be drawn thinner and maintain the same stiffness and therefore are lighter at the cost of being more prone to dents etc
Tubes in a frame are pulled, compressed, twisted, all of which stiffness = better

Yeah the different steels are basically the same stiffness as a bulk material, but posh steel has higher yield strength and higher hardness, which means it can be formed into bigger diameter, thinner walled sections, which are stiffer than smaller diameter sections of the same wall thickness, while mitigating the risks of tube buckling and denting.

I think the chat about bulk material properties for steel Vs aluminium alloy Vs titanium Vs carbon etc is not very informative.

Posher steel = flashier stickers = more instagrams

The stiffness is eaxctly the same across the tubes (207Gpa).

The strength varies which does allow for thinner tube walls to save weight with better grades, but then the tube diameter has to be increased to get the stiffness back. My 953 track frame has 0.35mm walls in places and decently oversized tubes to make it very light and stiff but it will dent easily.

ie Wot @Cupcakes sed

The stiffness is eaxctly the same across the tubes (207Gpa).

Yeah you're right, I had strength and stiffness the wrong way around

Sorry your original post was a bit misleading.

Steel is an alloy. The stiffness depends on what and how much is mixed with iron.

What I think you meant is carbon steels for bike frames are v close in properties.

Yeah I get ya.

TBH I was surprised that the Reynolds given values for mild steel/CroMo are exactly the same as for stainless.

Yeah I guess it's the perfect 'recipe' for a frame builder with each alloy proportion.

Obvs if you oversize Aluminium alloy it overtakes the narrow gauge steel etc.

This weight weenie chat almost makes me miss amey's posting of shitty treks

Whenever a customer goes to a frame builder wanting to select their own tube types, the frame builder should read this chat to get a nice lil reminder the customer hasn't got a fucking clue

Whenever a customer goes to a frame builder wanting to select their own tube types, the frame builder should read this chat to get a nice lil reminder the customer hasn't got a fucking clue

I confidently reckon that most framebuilders are bullshitting anyway when "selecting different tube combinations to suit your riding style"