Join Date: Apr 2007
Location: Syracuse, NY
Bikes: 2008 Novara Randonee - love it. Would have more bikes if I had time to ride them all. Previous bikes: 1968 Motobecane Mirage, 1972 Moto Grand Jubilee (my fav), Jackson Rake 16, 1983 C'dale ST500.
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I'm going to play curmudgeon and not speak to your original question. I'll leave alone for the moment how much you will use any of the higher gears, although your choice of a 53 large does come into play. Because you went that large you are somewhat forced to go larger on the middle ring. Because you also chose an extremely low range for the granny you then have a huge jump between that and the middle. The effects are this:
You have a 75% jump in gear ratio between the granny and the middle gear. Perhaps that is acceptable to you because you anticipate a lot of steep/difficult climbing, and the granny is typically not used as much.
HOWEVER, because the middle ring is relatively large, the lowest gear combo on it would yield about 9 miles per hour at 90 rpm (8 mph @ 80rpm). If you go any slower than that you will be forced onto the granny. If you are doing fully loaded touring, which I would expect when you are going for such a low granny range, those speeds could be quite common, resulting in too frequent shifting and a lot less enjoyment.
If you are planning a 10 speed cassette it's not nearly as ideal as a 9 speed, but the common 48/38 combo came about for a reason, and I question if the "benefit" of pedaling downhill at 40+ mph rather than tucking down and coasting is worth the cost of messing up the useability of the middle ring.
p.s. On the topic of too frequent shifting, I found out the hard way that there is one decided downside to brifters for touring that I had not anticipated. When I was on a tour in Italy I had a much longer and much hillier day than anticipated (long story). As a result I was using my left brifter very frequently. As the stroke required for a chainwheel shift is fairly long and requires more force than a rear cog I ended up with a sore hand.
Last edited by cny-bikeman; 06-19-12 at 07:35 AM.