Better suspension that is less likely to bottom out, fatter tyres, could be line ball. Plus a lot of modern frames have got it figured out about where failures might occur. Early MTB frames had to figure this stuff out by trial and error effectively.Modern geo and suspension would have to be placing more stress on frames, now that bikes are more capable.
Economies of scale really. A lot of steel frames are relatively smaller batch. But in reality it's a bit of what the buyer will pay as well. There is no reason why a run of the mill steel frame should cost a lot more than alu (maybe more shipping weight?). If you look at wholesale markets like aliexpress, steel and alu frame prices are comparable.What I don't get is steel frame bikes cost more (a lot more) in the bike shops than alloy yet with kmart bikes the cheapest of the cheap are steel and their premium $180 bikes are alloy.
There is a difference in using scaffolding to build bike frames (Kmart) and premium butted and treated steel tubes like Reynolds etc.What I don't get is steel frame bikes cost more (a lot more) in the bike shops than alloy yet with kmart bikes the cheapest of the cheap are steel and their premium $180 bikes are alloy.
Not always. My customised, hand made/painted Stanton frame was about the same as a name brand, Taiwanese made alloy frame.What I don't get is steel frame bikes cost more (a lot more)
Weird question, I was speaking to a local bike mechanic on the weekend. He's been in the industry for over 20 years.....
Sounds like a salesman rather than a mechanic.What a surprise, a 'bike mechanic' that doesn't know what he's talking about.
Also Reynolds alloy. Cracked a couple of alloy bikes, but never a ReynoldsThere is a difference in using scaffolding to build bike frames (Kmart) and premium butted and treated steel tubes like Reynolds etc.
That's because it's jolly old Pommy metal.Also Reynolds alloy. Cracked a couple of alloy bikes, but never a Reynolds
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That's because it's jolly old Pommy metal.
Unless it's a Trek. Two world cup level frames replaced no questions asked.Cost of replacement would be the reason Alloy has lifetime warranties and high end carbon or Ti have 5 year.
I'm hoping Trek has accurately calculated the endurance limit on the flex stays. It does play on my mind the stays are always stressed and are designed to give the final 5mm of travel.Fatigue stress depends on both the cycles and stress range. S-n curves are an approximation on this phenomenon, but ultimately big hits and lots of little hits are going to fatigue the material. How much is one big hit vs many smaller hits is the question. Interestingly theoretically carbon and steel (including titanium) has an endurance limit. That is under a certain level of stress these things should last forever. Aluminium does not. That means even for the smallest stresses, if given enough cycles they will crack. The reality of course is that steels will crack at the welds which have different properties as well as concentrated stresses, and carbon will have voids and other imperfections that mean their life is in fact limited.
Quite a few bikes adopt this philosophy. Giant and their cheaper stance (in fairness they made this simplification cheaper for the consumer) Spesh with their Epic evo (they just took the profits and still priced it high lol).I'm hoping Trek has accurately calculated the endurance limit on the flex stays. It does play on my mind the stays are always stressed and are designed to give the final 5mm of travel.
They are all carbon frames, but I understand your point.Quite a few bikes adopt this philosophy. Giant and their cheaper stance (in fairness they made this simplification cheaper for the consumer) Spesh with their Epic evo (they just took the profits and still priced it high lol).
One of two thing can be designed into the flex 'pivot'. First they can reduce the stresses in the material, which usually means thicker and more material, but this in turn affects the stiffness of the member and the flexstays don't really work anymore. The other approach is to increase the stringency of heat treatment on the alloy. The point of this is to reduce the initial flaw sizes as much as possible and this has an order of magnitude impact on the propagation of cracks. Am I confident any of this gets done? Hell no.
The marketing and bean counting department probably runs the shop and just calculate how many people will actually get to the point of breaking them and then of that subset how many are original owners and then within that, how many will actually get a refund. Balance that against the profits and voila!
As a side note, be interested to see how many stress cycles a flex stay endures. The member would be under a fair bit of stress and every single bump is going to be one cycle. Most alloys are lookng at 10^6-10^8 fatigue limit depending on a range of factors, I can see that getting eatn up quickly for a bike that's ridden a fair bit.