Custom Cassette ratio
 

I waiting for my new compact crank to arrive to replace my standard crank. I'm currently using a 12-26 SRAM force cassette and in the interests of riding up some steep hills (and because the compact only goes to 50) I was thinking of replacing the cassette with an 11-28.

The 12/26 includes: 12,13,14,15,16,17,19,21,23,26

The 11/28 includes: 11,12,13,14,15,17,19,22,25,28

Has anybody ever mixed and matched cogs? I'm thinking I'd rather have a 16 than a 12. I rarely use the smallest cog unless I'm bombing down a hill so I can't imagine missing a 12 much. I don't know if there would be shifting issues going from 13 to 11 though.

Older shimano cassettes had 3 bolts holding a bunch of cogs together.

You can tear those down and change pieces.

newer stuff , makes sub carriers in 1 piece, of alloy,
so, more compatible with lighter non steel freehub splines.

& then only the top 2 smallest cogs are loose.

My recommendation would be to use the 12,13,14,15,16,17,19,22,25,28. The 13 to 11 jump would be too big. The 12 needs to be the first position cog with the built-in spacer. The 50 - 12 combination would be big enough, good for at least 33 mph at 100 crank rpm.

If I recall, SRAM Force cassetttes have separate spacers for each cog - nothing pre-welded like my old Shimano stuff. I could be mistaken, I'll know for sure in about 2 days when I take it apart again.

So Al - why do you say it would be too big? That's my suspicion but I'm wondering what the reason is.

In most riding conditions shifting from the 13 to the 11 will instantly cut your cadence and momentum too much unless you are charging down a steep hill. There will be more situations where the 12 will fit your needs better. Empirical studies have shown that most riders perform best in a cadence range of about 85 to 105 rpm.

OK, I was afraid you'd say something about technical performance. The only time I reckon I"ll be in the 11 is exactly charging down a steep hill.

I'll probably try the 11-28 as-is for a while to see if I miss the 16. I have no way to track which cogs I'm normally in without looking backwards and I haven't been that interested in it till now. If I find too large of a gap, I may become interested. :)

The problem with the SRAM 11-28 cassette for me is the big jump from 19 to 22, right near the middle of the cassette. I gave up on this cassette for this reason. Shimano's 11-28 cassette avoids this by putting a 4-tooth jump at the top end (24 to 28), which is an improvement. However, I also don't feel like the 11 tooth is necessary, so prefer a 12-28 or 12-30, which Shimano now make as part of the Tiagra series; a new lighter, Ultegra-level version should be becoming available this summer.

Welded? No.

Old Shimano cassettes may be rivetted together. Easy to drill out the rivets too; they're not necessary.