After reading the Can Paired Chainrings be Mixed? Q&A, I have a question concerning cassette options.
For example, Shimano makes an 11-32 cassette with the following teeth: 11, 12, 13, 14, 16, 18, 20, 22, 25, 28, and 32 teeth. (As does SRAM). I would gladly give up the 11t cog to gain a 30t cog. Simply, the difference in spinning out with 11t versus 12t is nearly unnoticeable (to non-racers) while the jump from 28 to 32 is (going to be) very apparent. Is there either an off the shelf or DIY solution to this?
Thanks for the question, Tal. Unfortunately, the choices for changing the large cogs on cassettes are limited by the fact that some of the cogs are riveted together and working as one piece. You can only replace that “group” of cogs with another made by the company that made your cassette.
And, since they make the cogs to work with the rest of the cassette, the cog sizes that are available are pretty standard, not as custom as you mentioned (that 30 between the 28 and 32).
If only someone made a cog carrier and cogs that attached with bolts, then we’d have a way to customize our cassettes to our heart’s content from any combination of cogs we had taken off other cassettes.
I think the reason we don’t have anything like this is because the companies are focused on providing wider range gearing, with much lower low gearing INSTEAD of trying to give us more gearing in-between, in the middle of the range. And, as a result, we’re ending up with some pretty big jumps.
The engineers would probably justify the big jumps shifting up into easier gears as appropriate since as the grade steepens, the bike speed decreases drastically, so a big change in pedaling effort makes sense. But, I have been on hills where what you need is a small change to make it just a little easier, not a huge change where you are suddenly spinning at a too fast cadence.
In any case, for the time being, the best you can do is to look for a cassette that has most of the gears you need for your riding. If you’re lucky, and you keep checking the newest offerings from Shimano, you might find one that’s a little closer to what you would like than what you have now.
Hope this helps,