I wouldn’t say it’s the main problem…
It’s true the aluminum has no hard endurance limit, but it is still very high, like millions cycles high.
The main problem would be the stresses, very good aluminum is in par with shitty steel in terms of yield/failure stresses.
And good steel/alloy/tempered/whatever can be twice or more stronger than very good aluminum.
Sorry for cutting in on this tread…
There are several replies which speculate on good/bad design or guesses whether this or that diameter is enough… All have some merit but pointless without analysis and numbers.
Let the vendor present his design and judge on the results and field tests, which is what matters at the end.
I’m also curios to see what will happen with this product, just don’t kill it before it had some chance…
I can help with the calculations.
Dani (doing stress analysis since 2003, and not affiliated with any vendor)