hello I am planning a 6 week self supported tour in june from montana to california. I purchased a near new GIANT EXCURSION bike built for touring with fenders and racks. I will weight 310 pounds bike me and gear when i leave. The bike is currently geared as follows 14 32 rear cassette and 48 39 28 front shimano 105 equipment. Currently I have 23.8 gear in low and inches 93 in high. I would like to get to 18 and 100.
I have looked for a mega range 11-34 cassette with no success and have no idea what to do for the front gear rings.
I am frugal/cheap in that I will buy good used re the bike when appropriate and new when its smart like new tires and chain.
So with that in mind how do I get to my goal of 18 and 100 gear inches with out spending too much and changing derailers etc.
I NEED HELP IDEAS BRANDS the more specific the better.
Most of what I have leaned is from reading on this forum so thanks for being here and sharing the wisdom.
JOHN