Originally Posted by
brucedelta
I recently got an FX4 Disk and am new to the whole bike thing, but would like to learn some more. I was just trying to understand the idea of changing the cassette. If I understand correctly the 11-42 stock uses the larger numbers when climbing hills which you do not really have in your area. But the lower numbers are when you want to go faster with one crank rotation spinning the back wheel more times. But going to an 11-34 or 14-28 just seems to me like it would narrow the gap/difference between each gear selection. While you get no more uphill pull by eliminating the higher count rings, I would think you want to make the lower count lower so you could get more push.
Maybe I am just not a good enough rider, but so far I have not felt the need for an in-between gear on my FX4, but I have found myself on the smallest ring more of the time than I originally expected. Bottom line if I were to opt for a change I would think a 9-42 or something could be desirable(if they make such a thing as a 9 tooth sprocket), but I am asking to understand how the 14-28 is beneficial. I would think making the front crank larger would have the desired effect.
The main reason for me moving her to the 14-28 is that while she is not going to be a speed demon, she will never use the 11, 12, or 13 tooth cogs which are going to be harder to pedal with the single chain ring up front, and to deal with the wind. Her general avg speed never typically tops 14-15 mph over large distances, and as the tallest "mountain" we have around here is called a bridge, and is 108 ft at the summit, the 28 tooth is plenty of climbing gear for her. The wind can get pretty strong here and notorious for switching directions mid ride, and I like having single tooth gap to deal with it, versus having 2 or 3 tooth gaps. I do not race, rarely if ever used the 11,12, or 13 locally anymore, have no worry about spinning out going down hill on a 108 ft bridge, and usually, just casually riding at an 18-20 avg mph. The 14-28 cassette works perfect for that scenario. If the wind kicks up in my face, the one tooth difference can make all the difference in hating life or enjoying life and I like to keep my cadence consistent. Now if I plan to ride with a group I know if going to be going fast, I can bring out my Emonda and use a 11-25 or 28 I have, but as I approach my 60's, riding 24/25 avg over 40 or 50 miles in not something I am doing on a regular basis, so for me, the 14-28's are exactly what the doctor ordered.