i have to be honest i hated this bottle when i first bought it. kept ending up with sports drink all over the bike when riding over anything but smooth terrain + the noise it made was really bad (rattling).

I went home depot, picked up some fat 1.5" thick velcro (the really heavy duty stuff) wrapped the female around the tri bar and stuck a huge great wad of it on either side of the bottle.

once in place it doesn't move an inch or make a sound

great and cheap fix