Another Gearing Question: Old vs New

[HillSlugger]

I can work out a nice shifting pattern with the standard crankset and the 11-34 cassette, but I can't make it work out well with the 12-25 and a 28-39-50 up front. All the jumps from crank 1 to crank 2 are in the 25% range.

Thanks for letting me know that the 34 cassette would require a new derailler. I don't really want to do that. Can I get away without if I only go to 12-27?

I know that our hills are mere bumps, but at my level of training they are still hard!

Let me do the math with the 12-27.

[Triskeliongirl]

You just need a standard road triple derailleur for a 12-25 or 12-27 casette. I run a 50/34 in front with 12-27 in the back, and this gets me up anything in the texas hill country. For loaded touring or real mountains, I do have a 11-34 casette, but as I said I really prefer the 12-27. If you have a 30 in front that is plenty low when paired with the 27 in back. When you look at the ratio charts, don't think about shifting between rings in front as much as choosing a front ring, and then shifting up and down the back, which is the modern style with 9-10 speed rear casettes. You will probably just wanna be in your 50 for flats, shift to the middle if it gets hillier and to the granny when it gets really nasty. Also, its important to get over the idea that you will fix up your bike to do one thing and one thing only. While I have my 12-27 for *most stuff*, I have a touring wheel with an 11-34 that I can put on my touring bike (which does have a long cage mountain derailleur) when I need it. Once you learn how, swapping casettes is also an easy option. I personally think a mountain rear casette is overkill on a modern light triple. I need it since I only have a double.