Originally Posted by
Hypno Toad
I'd love to find a better solution to getting a second bottle on my wife's bike. The frame is so small that the seat post bottle rack doesn't allow enough room to fit a small bottle. She makes it work, but not great. Anybody else have issues like this? Ideas to make the seat tube rack work better?

For any ride much over 10 miles, I strongly prefer a Camelback or similar hydration system.
There are a number of seatpost mounted hydration systems as well, none of which need a bottle.
If a bottle it must be, I would rather carry that on a belt device than on the bike for ease of access:
Mercury 2 | Nathan Sports