Seat stays?
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Seat stays?
I have seen seat stays joining the seat tube at the junction of the top tube and then lower on the seat tube. What is the benefit of the two different designs?
I apologize in advance for my ignorance, Frank.
I apologize in advance for my ignorance, Frank.
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the seat stay joint is one of the very few places on a frame where a builder can really express their personality. Other than that, there isn't any substantial difference. Although some builders disagree with that assessment.
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When I was at Cyclery North we built a stay design we called Helenic, the seat stays crossed the seat tube just below the top tube junction and butted into the top tube just before the seat tube. Much like GT's triple triangle but usually with a more equilateral triangle look as the sizes were larger and stay angles steeper.
Eddy, the boss, claimed this made the rear end quicker, whatever that meant beyond the obvious marketing BS was beyond me. The look was easily noticed, like curly stayed Hetchins. With the right rider these bikes were fast. With my tourist legs even the after build up test rides were a lot slower.
I will say that without extra care, like sleeves or "landing pads", the thin walled sections of seat and top tubes are poor receivers of stays. Andy
Eddy, the boss, claimed this made the rear end quicker, whatever that meant beyond the obvious marketing BS was beyond me. The look was easily noticed, like curly stayed Hetchins. With the right rider these bikes were fast. With my tourist legs even the after build up test rides were a lot slower.
I will say that without extra care, like sleeves or "landing pads", the thin walled sections of seat and top tubes are poor receivers of stays. Andy
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AndrewRStewart
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you can do a lot of things with carbon that you can't do in other materials. The volagi stays or Spec robaix stays really are a similar but different subject to the OP's question, I think.
You can patent any idea you like nowadays. Seems to me that Volagi just bought the right to sue, they weren't really protecting an idea of any merit. And Spesh sued them instead. You think they had a dynamicist check the response of those stays? I don't.
You can patent any idea you like nowadays. Seems to me that Volagi just bought the right to sue, they weren't really protecting an idea of any merit. And Spesh sued them instead. You think they had a dynamicist check the response of those stays? I don't.
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So if I am understanding what has been said so far there is no benefit one way or another to the different designs?
Frank.
Frank.
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Frank- I think you'll find that a few PSI difference in tire pressure will be a vastly bigger influence then the way that the stays are attached. Structurally I think attaching the stays closer to the top tube/seat tube junction is better. My marketing department feels otherwise Andy
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This makes me think of the term "node" they use in building automotive roll cages. You want to join tubes all in one place in their paradigm. It makes things stronger. So that logic says its better to join the seat stays at the seat tube/head tube joint. If you join a few inches below that you can put a twisting force on the top of the seat tube. The amount of force and the strength of a seat tube with another tube inside it I don't think you're looking at enough of a stress there to worry about. If it was for an application with many tons of force coming up that seat stay, then that would be different. Makes no difference how the seat stay joins the frame.
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Thank you all.
Frank.
Frank.