Originally Posted by
dminor
I do not doubt at all the strength of I9 spokes - - but "machined from billet" in and of itself does not imply strength; especially since we both know an aluminum piece that is manipulated by forging can be much stronger than its machined billet counterpart.
I wasn't trying to imply that billet made them stronger. They're stronger for other reasons (described in I9's FAQ).
I could get 2prs of HP2's that have proven 4-5yrs strong for the price of 1pr of I9's. I think the argument is hitting that point:
Ah yes, of course. Welcome to bikeshoppingforums™, where technical discussions of leading edge cycling products are subverted in order to make room for "which clapped out early 90's POS can I get for under a hundred bucks" threads.
Originally Posted by
corvuscorvax
And aluminum actually has a lot
less resistance to stretch than steel: aluminum has a
Young's modulus of 60, and steel has a Young's modulus of 200. That means that you have to make aluminum spokes thicker to achieve the same spring constant as a steel spoke. Steel also has a much higher
ultimate tensile strength (860 Mpa) than aluminum (483 Mpa).
I9 spokes *are* larger in diameter. And steel's ultimate tensile strength is compromised when stress risers are introduced during the manufacturing process. So perhaps the difference is not as significant as you think.
Originally Posted by
corvuscorvax
So I guess I don't see your point.
No point really - just trying to help you understand why something works when you think it shouldn't.