My Genesis CdF has a Shimano Sora FC-3550 Compact Chainset 50/34T and a 9 Speed Cassette Shimano CS-HG50 11-30T.
My previous bike had a Triple Chainset and, for commuting, I stayed on the centre ring. With the Compact, I am not sure what to do; I find for commuting the big chainring is fine as I usually stay in the middle of the cassette.
I’m not near my bike at present, but I thinks these are the correct ratios plugged into Sheldon Brown’s gear calculator:
50 47.1 % 34
11 9.1 6.2
9.1 %
12 8.3 5.7
8.3 %
13 7.7 5.2
15.4 %
15 6.7 4.5
13.3 %
17 5.9 4.0
11.8 %
19 5.3 3.6
21.1 %
23 4.3 3.0
8.7 %
25 4.0 2.7
20.0 %
30 3.3 2.3
If I am looking for a low gear and change midpoint on the cassette (at 17/50) there is a huge drop down to a much lower gear at 17/34.
Is it OK to stay on the big chainring throughout the cassette?
My previous bike had a Triple Chainset and, for commuting, I stayed on the centre ring. With the Compact, I am not sure what to do; I find for commuting the big chainring is fine as I usually stay in the middle of the cassette.
I’m not near my bike at present, but I thinks these are the correct ratios plugged into Sheldon Brown’s gear calculator:
50 47.1 % 34
11 9.1 6.2
9.1 %
12 8.3 5.7
8.3 %
13 7.7 5.2
15.4 %
15 6.7 4.5
13.3 %
17 5.9 4.0
11.8 %
19 5.3 3.6
21.1 %
23 4.3 3.0
8.7 %
25 4.0 2.7
20.0 %
30 3.3 2.3
If I am looking for a low gear and change midpoint on the cassette (at 17/50) there is a huge drop down to a much lower gear at 17/34.
Is it OK to stay on the big chainring throughout the cassette?