Putting water on your fork sliders is inadvisable, unless you prefer
highly aerated drink and massively increased unsprung weight.  If,
indeed, these appeal to you, by all means proceed to your local
hardware and obtain worm-drive hose clamps appropriately sized to
fit your sliders. Employ a pair of clamps to attach each water bottle cage.
A piece of inner tube rubber placed between the cage base and fork
slider may help to protect the finish of the latter and prevent slipping
of the former.

   Others may offer suggestions as to means to retain the bottles in
the cages.

                    -- darryl skrabak
                       San Francisco