Custom 12-32t cassette

The cassette holds the cogs or gears on the rear wheel. I had always ridden with wide range cassettes, whose spacing between the gears resulted in bigger jumps in the effort required for pedaling. Then I got my Aero, which came with a narrower range of gears for road bikes. The advantage of the road cassettes is you have gears more closely spaced. So, if you want to pedal just a little bit harder or easier, you can shift gears and not get a big change. The disadvantage is that you don't have the lower gears for hills. I got use to the road cassette, but found I wouldn't mind having a lower gear for hills, so I wouldn't have to shift the front onto the granny chainring. But I didn't want to give up the close spacing of the gears that I use most often.

Somewhere on a forum, Bacchetta's I believe, a person described how to create a custom cassette by changing the 12-27t cassette to a 12-32t.

You take the cassette off the bike and remove the 14 tooth cog. Buy a 32t cog and use the spacer that was between the 14t cog on the back of the cassette. Then add the 32t cog on the back. There are a number of videos on the web that show how to remove the cassette from the wheel. I bought the 32t Shimano Hyperglide sprocket from Harris Cyclery. The picture shows the 14t and 32t cogs and the spacer.

The gearing changes from 12,13,14,15,17,19,21,24,27 to 12,13,15,17,19,21,24,27,32. There's a big jump to the last cog, but I only use it when climbing a steep hill.

 I've been riding with this cassette for awhile and like it. I still have the closely spaced gears, but now have an easier gear when I hit a steeper hill. I rarely use the granny chainring on the front now.