Originally Posted by CrossChain
You got it, Centex. A 39x23 will give him a 46inch low, a 34x23 will ease that off to a 40. For me, it takes about a 3 inch difference to really be noticable. Berts is probably a strong rider...for terrain so varied, I'd go on to couple that compact to a wider ranged cassette-- but thereby give up a greater selection of gears to use in the narrower range we ride in mostly. Most of the time, we need only a slightly lower gear for head wind, rollers, etc. Hence Berts desire for a second wheel, or wider range cassette, to use for climbing days. Mozeltov!
*Berts, I just realized I'm speaking for you...apologies.
No apologies needed.
I chose the 12-23 because I like the small differentials between changes enabling me to maintain cadence and speed over the varied terrain and conditions you mentioned above - however when it comes to monster hills that's another story. Since I know the type of terrain I'll be riding in advance, I figured it would be best to have a dedicated hill climbing wheel with more suitable gears.