I have some questions on what size chain ring is most appropriate for me. I would appreciate the recommendations of the list. I have narrowed my choice to two options:*
•Truvativ Isoflow 22/32/42 (http://bikesmithdesign.com/Short_Cranks/IsoFlow.html
•Truvativ Isoflow 28/38/48**
Whch of the above chain ring combinations would be best for me?
Here is some background:
•I plan to use the bike primarily for commuting & hauling heavy groceries & then next year for loaded touring.
•I am 5’11” & 170 pounds
•I am likely to purchase one of the following – Trek 520, Surley LHT, or Bianchi Volpe & mount the chain ring on one of these.
•I will use 700 wheels
•I prefer a triple chain ring
•I live in New England where long steep hills are abundant
•My knees are arthritic
•I will be riding the bike with short (145 mm) crank arms, which I will soon be purchasing from BikeSmith***
I have an additional question: how if at all does having short crank arms impact the choice of chain ring tooth combinations?
* For the reader’s reference, I have settled on these two chain rings because they are the most affordable triples available from BikeSmith that will accommodate short crank arms
** Kindly note that I have the option to substitute a 26 tooth Shimano ring or a 24 tooth Sugino ring on the 28/38/48.
***Unfortunately, Mark at BikeSmith was unable to recommend a particular set of specifications for the chain rings.