Originally Posted by
timdow
First off, you probably don't want to try to go with more cogs in back. This would require a new wheel, and more problematic the spacing of 8,9,10 speed wheels is wider and it not recommended to spread an aluminum frame. Also, you would need new shifters.
My trek is already spaced out to accommodate up to an 11 speed cassette with proper hub. And a new group set would come with shifters. If I run the biggest tiagra cassette and then put an mtb crankset on for the time I'm actually touring I think that I can get the best out of both. The tiagra cassette gets to a 32 tooth low gear and paired with an mtb crankset that would achieve the gears you guys are suggesting but then I can switch cranks in the plains to get extra speed on the flatter parts of the country or when I'm riding around where I live