Maybe this should be a different thread, but on a related issue, what do people think about tire size. My trek pilot 1.2 came with 28s (as well as Alex rims). Is there a real performance benefit to going down to 25s (wich I think will fit on the rims) or even 23s (which I'm not sure about fitting)? And conversely how much of an adverse effect does going thiner have on comfort?

BTW: about 1200 miles on the bike & I'm still trying to fine tune things. Unfortunately, the season around here is almost over & I'll have to let my butt get soft over the winter, before I have a chance to consider changes next spring.

Dan