I have the bottle holder on the handlebar. On the framework I have unfortunately no place and under the saddle for me is not a solution. That reminds me the bottles flew in a high arc out at various holders already with smaller potholes. This holder holds my 750ml bottle safely and securely. Unfortunately, the holder rotates on the handlebar, no matter how solid you pull him. Something double sided tape including but works wonders. If the bottle to the driver pointing mounted, you can possibly come with the knee because when you have to out of the saddle times. So if you forward has space and no trains in the way that's probably the best position, so the bottle in the direction facing forward mounted.
