On bike storage when water bottles attached to seat (S3) - Suggestions wanted

Hello, I recently acquired a new, used bike for myself.
It is a small 48cm frame, Cervelo S3 (2015/2016).
It came with a double water bottle cage that attaches to the rear of the seat.
The cage, combined with the aero seat post (as it is larger in circumference than a standard seat post), I am at a loss on where and how I can carry some needed supplies (e.g. a tube, tire irons, CO2, multi tool, etc).
If anyone has any suggestions along with specific product recommendations that would be greatly appreciated.

I could abandon the seat mounted cage and try to fit the standard location for water bottle (freeing up the space under the seat), however, I would like to keep the current set up if possible (as it is probably more aero :slight_smile: ).

One option is: Topeak Tri-Backup Elite Co2 Bottle Cage Angled Saddle Rail Mount, which has fittings for CO2 and tube. irons and multitool then go in your pocket.
Or mount a slim cage with a storage bottle in the usual place.
O put it all in pockets.


You could use one of the bottle locations for a bottle with your flat kit in it? Depends on how much liquid you need to carry on the bike I guess though. I don’t know if the Torhans VR aero bottle would fit that small frame, but if it did you can cut the bottom of it off to make it a spare kit holder (I do this on my Felt B14 tri bike).


I have a Cervelo S1, basically the alloy version of your bike.

Are you set on the seat you are currently using? Some (like the Specialized) come with mounting points to attach storage under them. I have the Power saddle and use the Spec Road Bandit for storage. It works great. Before that everything just went in a jersey pocket.