I am using Arundel Mandible carbon fiber cages to hold Specialized bottles.
These are attached to the rear of my saddle with an older xlab hydration system (not even sold anymore), which holds one bottle on left and another on right hand side (xnut and CO2 between the cages).
On almost every ride, if go over a bump on the rode my bottle gets ejected.
Besides going over the bumps on the road could this be due to:
a) bottles
b) cages
c) xlab rear carrier hydration system
d) all of the above
suggest not putting bottles back there as a first solution. Usually you can put one in the main triangle and one between the arms which is usually plenty, if you need more, jersey pockets can hold 3 more.
If you must put bottles back there, try different cages that grip the bottles tighter.
OK! ! ! I spent at least 3 years and $200 trying to figure this out, and I Finally figured it out. I REALLY did! ! ! Your cages are fine, those are exactly what I use. The KEY to the problem is the bottle. I, of course, like to use insulated bottles, but they FLY out Every ride. You have to use the standard, plain Jane bottle that you get at your local bike shop. The ones they put their advertising on. Now I will say, some shops will use an obscure bottle. You need the notch in the bottle to fit perfectly with the top lip of the bottle cage. The insulated bottles are too heavy, and they launch very easily cause of their mass. In the last two years I have done 3 full IMs, and 2 halfs. I have had not ONE bottle launch. In my long races I start with 3 bottles of Infinit, and then get 3 more at special needs. So I have those bottles on my bike all during my race. It’s the bottles, not the cages. You can always use one insulated bottle on your frame. Living in Texas, I like having cold water, but not at the expense of having to stop and go back for bottles!
Try the Bontrager RL rear cage. I’ve used a number of shaped bottles and haven’t had a bottle eject in the 3 years I’ve used it. It’s not carbon but it works! There’s space in between bottles to attach a tool kit if desired.
I still don’t understand the need for behind the seat cages. With one on the frame, one between the bars and one in jersey pocket that good for a 2-3 hour ride even here in Texas in the summer. I like to stop at least that often to take a leak which makes it easy fill them up at stores along the way.
Not to mention that it’s a safety hazard. It’s a matter of when it ejects not if it ejects and that is a safety hazard for everyone else coming down the road.
Rubberbands. At least that is the only thing that has worked for me. I loop the rubberband around the cage and then around the nozzle of the bottle. It does make it more difficult to grab a bottle for a sip, but I usually keep one bottle on my down tube and only reach for the rear bottles when I need to swap that one out. Once you get good at it, it is doable to remove and reapply the rubberband on the go, but I found that once a bottle is empty, it is less likely to launch.
So let’s say you have the extensions too close together for bta and hate extra weight on the bars making them feel unbalanced. Do you use a single behind the seat bottle (less likely to launch due to cage angle) plus one seat tube aero bottle and take 2 hand offs. Or 2 behind seat and 1 hand off, or aero bottle on down tube and standard bottle on seat tube and no bottles behind the seat?
I have been having good luck with a gorilla cage and a aluminum cage back there. But it would be nice not to worry about them. I haven’t done a lot of hand offs and have heard that even in a 70.3 they can cost you significant time if your average speeds are over say 23mph.
I’d try different bottles as a first pass. If not, I’ve had success with crazy gluing a tiny piece of inner tube to the inside of upper lip of the cage. It provides just enough resistance to prevent the bottles from slipping.
I would second the rubber bands. Looped through the frame of the bottle cage holder and around the neck of the bottle.
I use it for my behind the saddle ones (have a twin bottle set up). My between the bars one seems to behave, so that’s where my bottle lives when I’m drinking from it. Swap out while still in aero by putting the empty bottles back once empty. Empty bottles don’t seem to torpedo.
I tried bontrager aero bottle on the down tube and standard cage on seat tube on a ride this morning and liked it. Easier and faster to grab both bottles. Lower cg makes the bike feel more balanced too. I may still do 1 bottle behind me just for storage. Sometimes there may be something for keeping it simple.
Seems like I’ve seen pictures of pros doing a little of everything.
Drugstore brand hairbands… got me through several half IM’s and one full so far. Rubber bands probably work too, but you can get a big pack of hairbands like the ladies use for dirt cheap and they are easy to find in your tri bag pocket.
How and where exactly do you use that stuff.
Do you attach it on the parts of the bottle cage that make contact with the bottle to get a tighter fit?
This could be a great option.