Nickldn wrote: ↑Thu Mar 28, 2024 2:21 pm
Curious why you want to use titanium spokes as a retrofit. Theoretical weight saving sounds good, but any concerns about change in overall wheel stiffness and impact on comfort/power transfer?
I hear that with carbon spokes the stiffness is usually greater than steel so using the same number of spokes on the same design of rim results in a much stiffer wheel (less comfort). This is why some carbon wheels use fewer spokes.
Does the same issue apply to titanium spokes?
Hello
I don't want to retrofit with titanium spokes, my wheelset isnt built yet. The finished bike on this thread is not mine
the reason that I want to go with titanium spokes is of course primarily the weight savings and second the cool factor. I am pretty lightweight (67 kgs) and not very strong so why not.
As for your question about stiffness relatively to carbon spokes, my engineering assumption, considering the fact that stiffness is really determined by only two things, the modulus of elasticity E and the moment of inertia I in the direction that interests us (lateral to the wheel/bike because that's when the spokes bend during a corner. When the bike travels straight the spokes are getting loaded only in tension), the first is an inherent property of the material, the second is determined of the shape and area, for steel vs cfrp, the cfrp spokes will have both E and I of greater magnitude. E because of the material properties and I because they are thicker usually, they end up stiffer.
As for titanium, someone could argue that it can also be stiffer than steel, beacuse due to it's smaller E and strength (strength not specific strength/weight ratio) compared to steel, the thickness must be bigger and that could also result in stiffer spokes because of the bigger moment of inertia.
there are finer details to that analysis, but thats what I can think, without at least checking every cross section and material properties to come to the conclusion why everything works as it does.
