Originally Posted by
Duragrouch
For me, I agree, I don't need a racer-high. Some folks do. What's more useless is just slicing the ratios into ever smaller steps.
DD3 torque limit: Now you got me curious. I can't find exact value online, just says avoid small chainrings. I wonder if applies to everything, or is more critical in low range, middle range (direct drive, so I think it's a dog-clutch that bypasses the gears), or high range? Digging deeper, AI references the torque limit for the cassette lockring, not a value for the hub. Just curiosity. The value is probably based on large wheels, so 20" wheels, providing the same ground thrust at lower hub torque, might be fine.
If I need a lower-low that a cassette won't solve, I've seen folks on here doing over 20T jump on 2X chainrings (since I can't fit a 3X on mine), between that and a bigger cassette, that would get me there, and kept simple.
For folks chasing speed, a 20" wheel is simply inapt. So is a heavy-ish IGH.
No, the max torque limit of the SDD3 was listed as a ratio. I've now forgotten what it was but I was right on the edge with 47T chainring and 36T max cog. It's moot now because the SDD3 is discontinued.
You can get 19-88 gear-inches with a 1x, 47T x 11-50T setup. What else,
real-world, do you need? Why you and others seek the heavier, more complex and more expensive alternatives is a real head-scratcher. KISS.