Originally Posted by
creativepart
My new bike (used) has a standard 39/50 double crank. I live in a hilly area and I need some lower gearing. My hybrid has a triple and I'm used to that. I guess there are three ways I could go. But I'm not sure which is "best".
I could change out my standard double for a triple. Or I could change it out for a compact crank. Lastly I guess I could just change the 12/26 9-speed cassette for 12/30 or even 12/32.
Triple.
At the same range you can keep your current gear spacing or run even tighter cogs for flatland rides than with a double.
50-39 x 12 - 13 - 15 - 17 - 19 - 21 - 24 - 27 - 30
50-34 x 12 - 13 - 14 - 15 - 17 - 19 - 21 - 23 - 26
50-39-26 x 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 21
If you really need it due to terrain, load, weight, and/or fitness you can have a 27% easier gear with the compact double (24 small ring vs. 33 which would take a 44 cog to match 24x32).
What would be best?
Triple.
Inexpensive compact crank or mountain bike cassette (might need a longer cage derailleur too).