jerky1280

I currently have an older Santanan tandem with an 8-speed setup - 12-32 in the back and 34/46/60 in the front. The wide range of the cassette is great for climbing, but I can't stand the big jumps between gears. I'd like to go to a more traditional road-bike cassette of a 12-25 or even 12-23 to give smaller gear jumps and make shifting a bit easier on the stoker. To preserve the low end, I'd change the chainrings out for a 24/38/52 setup for the 12-23 or a 28/40/52 setup for the 12-26. Obviously I'd be loosing the top end, but honestly, we've only used the 60/12 combination once or twice, and it was a bit much for my stoker.

Would a 12-23 or 12-26 be too narrow a cassette for tandem use? I'm concerned that I would find myself having to shift between chainrings constantly, which would be even more annoying then the wide cassette.

mkane77g

Either would be great. Depends on terrain/fitness. We switch between 12-27 & 12-23.

professorbob

If you do a lot (or even a little for that matter) of climbing, you might want to be in the range of low to mid twenties in gear inches.

waynesulak

Gearing is a personal decision depending on terrain, fitness and ride goals.

We use 12-25 or 12-28 cassette with 50-36-24 rings.

8 speed cassettes should be cheap so it is easy to try it.

Carbonfiberboy 

As above, it depends on how strong you are. Calculate your proposed low end gear-inches with an online calculator:
https://www.machars.net/bikecalc.htm
and compare that to what you have/want. Most of us don't need more than a 52 in front.

On my single climbing bike, I have a 52-39-26 in front and a 12-25 in back for exactly the reasons you give. Works great. Our team uses the same chainrings, but a 12-34 in back because that's how it has to be.

Dean V

It is also good if you can get a combo which enables you to do most of your riding without having to do alot of front shifting.

waynesulak

Yes that is why we switched from a 12-25 to 12-28 cassette. We really don't need the small 24 ring and 28 cog but we can stay in the middle or big ring much more on our routes with the 28 cog than with a 25.

merlinextraligh

As others have stated, it depends on your fitness and terrain. 11-23 works fine for us, with mostly flat, to rolling terrain. And with a triple, you still get a pretty low option in the small chainring, when we take the bike to the hills.

jerky1280

Thanks for the input. I'm going to pick up a 12-26 for the rear and go with 24-38-52 up front. That should result in the 52T being useful from about 16mph up, and the 38 from 12-22 or so.

I like Mike Sherman's gear calculator:
https://home.earthlink.net/~mike.sherman/shift.html

willhs

I would add a plug for gear-calculator.com, which gives a better visualization and allows for direct comparisons of setups. For example, here's the difference between your setup and mine (52/38 in front, 12-36 in back). I'm not saying mine is better, but it works better for my team and lets us use the SRAM Red shifters we enjoy. We've never had a scenario where we needed an easier gear.

https://www.gear-calculator.com/#KB=3...5&UF=2099&SL=2