Originally Posted by
lazerzxr
sorry to divert your thread Bianchi but I think its relevant and of interest to all to discuss since you have an identical hub to mine. My final thinking is this:
Jude has lots of experience and has built lots of wheels presumably all with this tension, it is reasonable to assume she does this because they dont fail.
My own experience of working as an engineer tells me CKs answer to my question may be a conservative blanket answer. The hub shell stretch issue will vary on spoke count and this was not addressed in their answer.
So, I will assume that 65kgf is a recommended tension for a 32 hole hub, they dont make a 36 so 32 is the worst case for flange stretch (apparently the limiting factor). This is likely a conservative number in itself. With 25% less spokes in my 24 hole hub I can up the tension by 25% without exceeding the recommended flange force. Based on Judes experience I will assume spoke hole robustness is not and never will be limiting.
For further justification, look at it the other way. IF 65kgf is recommended for 24 hole hubs based on flange force as the CK email suggests, then lacing a 32 hole hub to achieve the same flange force results in a spoke tension of 48kgf. That in my opinion is silly low.
Therefore to lace radial on a 24 hole hub using the experience of a builder and the advice from manufacturer with a bit of desyphering, the correct and conservative answer in my mind is...........
90kgf
Looking at it another way.... Bianchi states his weight as approximately 175 - 185# (I think), mine is approx 160# or 86% of Bianchi. 115kgf x 0.86 = 99kgf.......not far off
Like you I am just imagining what was really meant by the 65 kgf recommendation. Wouldn't it be funny (and isn't it somewhat likely knowing what we do) if the CK guy really meant MINIMUM of 65 kgf, not maximum? That almost makes sense!
I don't dispute your reasoning, but I can't think of any example of spoke tension recommendation that varies with the number of spokes. In my experience the limiting factor is the strength of the spoke hole in the rim, which doesn't change too significantly as the number of spoke holes increases from 20 to 32 or more. So rather than higher spoke counts corresponding to lower spoke tension, what I have seen is that higher spoke number wheels just have a higher total tension o+n them than lower spoke number wheels. Having said that, your analysis is perfectly reasonable. And the good news is that for front wheels 90 kgf is within the recommended range anyway so none of this matters anyway.