|Ice, water bottles, thermometer, and water|
|Fan, watch, thermometer, and water bottles|
There you have it, after almost 2 hours the water in the insulated bottle was still 20 degrees cooler than the air temperature. These results would probably vary if the bottles were placed in the sun and if they were subject to constant shaking as they would when placed on a bike.
We'll be buying a few more insulated bottles soon.