Originally Posted by
Fat Boy
An easy (easier) fix would be a compact chainring set (50-34) and an 11-28 cassette. That would be a little steeper than she's used to, but probably a better chance of success. If that doesn't work, get a triple for her.
+1
Only thing is a quick look around got me only 12-27 10s cassettes.
A 34x27 is about 1 gear higher than her lowest gear now (34" vs 30x24 which is 33.8"). If she can climb in her second lowest gear, a compact with a 12-27 should be fine.
If she uses the 11T then you'll have to fiddle with the cassette to incorporate that.
A gear inch, btw, is equal to the diameter of a big wheel bike (the old fashioned kind, or like on a kids tricycle). So a 30" gear is equal to about a 1:1 ratio for your (approximate) 27" wheel. In contrast, a 50x12 is over 112 gear inches - so if it was a big wheel, it'd be over 9 feet tall! The number really doesn't mean very much (isn't precise enough to measure how fast you're going, for example, unlike sheldon's calculator which is more precise) but it is good for relative comparisons.
hope this helps
cdr