FatBottomedGirl
Here is what I did on my touring bike that is mostly my commuter bike.
45-42-24 X 12,14,16,18,21,24,28,32,36
Here is my thread about what parts I used etc.
http://www.bikeforums.net/showthread...4-28-32-36)-o)
Here is a link to another explanation of the 42t center ring.
http://wheelsofchance.org/2009/08/28...-the-question/
I have thought a lot about this as it seems you have also and tried a lot of things until the light came on as to what was a perfect fit for me. There are several reasons I went with the 45t 42t combo. One was that that combo gave me a very good half step pattern, and in today’s 8,9,10 speed cassettes that is somewhat uncalled for. But most saying that are running very close spaced cassettes. With the wide spaced cassettes mtn like (non mega-range) I felt there was room for half step again. The next reason was with with two rings so close in size the 45t provided a much straighter chain line when on the smaller cogs, and it’s very noticeable when riding in those gears “smoother”.
I ride the bike like it was a double most of the time and have a great range of gears in tiny steps if needed with just the two rings. Then I have a totally different bike (mountain goat) when i make the harder soft shift down to the 24t granny. You may be happy with just a 26t granny especially if you use a 36t big cog cassette as I did. When I make the shift down to the granny I didn’t want just one bailout gear I wanted a range of at least 6 gears that took me up and overlapped a little the big ring range. Around here there are a lot of rolling hills and with this setup I didn’t find I needed to keep jumping between the granny and the bigger rings.
Most people riding road gear triples like a 52,42,30 have almost no use for the 52 as it gives you one or two more higher gears but they are so high most people can’t use them except going down hills. The 52,42 does give you a “one and a half step” pattern but it’s too complicated to use effectively and the 10 tooth jump is a nice shift but not as smooth as you would want to make it and then remember to shift twice in the back just to get a in between gear. When you are on the 52 and want the gear range you would get on the 45 you become cross chained to the point you are straighter on the center ring.
The unexpected plus I found after I got my gears dialed is how smooth the 3 tooth jump is. I have STI index shifting and it shifts so smooth now I find myself looking down thinking it didn’t shift when it did. If I want a half gear higher or lower I can just pop the front over and get it or pop the front over and shift the back one in the opposite direction. Very easy to learn and the shift is so easy I find myself even shifting under power just as I would on the cassette.
Here is what it looks like.
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