Originally Posted by
awesomejack
Why have a crank set like 24-34-44? Why not have something like 24-36-50? It gives you the low gears and the high gears. Nothing is gained by having a 44 big ring rather than a 50. You use low gears in the little rings and high gears in the big ring. So why this choice?
Let's say you are using a Shimano mtn RD;
Typically it has a maximum wrap of 45T.
And you are using an 11-34 9s cassette;
You just used up 23T on the rear.
That leaves 22T difference *maximum* between the large and small chainrings.
So if you want a 24T small ring, the large ring cannot exceed 46T.