It turns out that bottles jettisoned out the back of a saddle-mounted water bottle cage, like depth charges, are not optimized for triathlon racing. Problems are legion when that happens, loss of hydration not the worst of them. Maybe this is why XLAB “won” the hydration count at the Hawaiian IRONMAN triathlon this past year, its widest margin enjoyed in rear hydration.
By “hydration” we’re talking anything from sophisticated drink systems in the front to simple water bottle cages behind the saddle, but also just cages in the front as well, which was (and always is) a popular set up among the pros in Kona.
XLAB has been a popular brand of bottle cages because you just aren’t going to lose a bottle out of an XLAB cage, whether mounted front or rear; whether used on road or off. In fact, Dawn to Dusk is a very popular brand of cages and other accessories used by gravel riders and if you think they look a lot like XLAB cages there’s no coincidence. Same cages, different finish. Same owner, different brand. What works for tri works for gravel and, in fact, I have rock-solid Dawn to Dusk cages on my bikepacking bike because I put 30 ounce Zefal bottles in those cages and ride that bike offroad.
For the purpose of this count, it wasn't the cages that were counted, but the brackets that hold the cages. In the case of Fizik the saddle is the bracket (with a few added pieces) and it's counted as Fizik. If it's an XLAB bracket it's almost always got XLAB cages on it. If there is 1 rear bracket with 2 cages attached it's counted as 1 unit.
Below is the chart showing the front hydration system brand use among the IRONMAN age group athletes in Kona and this ranges from integrated systems by Giant, Specialized, Scott and Canyon to semi-integrated systems by Vision and Profile Design. I say semi-integrated because if you take, for example, Profile Design’s Aeria Hydration that’s an aftermarket product you can put on most tri bikes, but that system is such an integral part of certain of Quintana Roo’s bikes – in some cases with special parts made just for those bikes – that it threatens to cross the line to an integrated system.
In fact, when it comes to front hydration there’s no consensus on how to do this. That’s why XLAB “wins” the count handily in rear hydration systems, which consists of a bracket with cages, while front hydration might be a bottle cage between the arms or it might be a refillable system like the Profile Design system described above, or Profile’s HSF/AERO HC 800 OR 800+, or Vision’s Metron, or its DS2. XLAB has its own front refillable systems, like the Hydroblade and the Torpedo Versa 500.
I didn’t see any brand preference notably different in the pro bike racks than was found in the AG racks. XLAB dominated in rear cages of those pro bikes, and its front systems were on about a third of the pros' bikes. The one difference was in how many integrated front systems there were. While front integrated hydration systems – hydration that was part of the frame, or proprietary and heavily frame-inspired – were on only about a tenth of the bikes in the AG race, about a quarter of the pro bikes used systems of this type.
What threatens to complicate all of this in the very near future are these new full forearm extensions (see our Aerobar count). For example, here’s the Vision TFE Pro made for Cervelo’s P5, that (to the best of my knowledge) 3 different male riders from Team Jumbo Visma rode to 1st in the initial Tour de France TT, 1st and 2nd in the final Tour TT, and 1st in the world cycling TT championships. It’s made for the P5 but works in the P3X and was in the P3X Ben Hoffman rode in Kona.
On the front of that bike Ben had simply a bottle cage (XLAB of course!). But if you wanted a refillable front hydration system what would you use with a bar like that? If your aerobar is the imperative, and you choose your front hydration system to mate with your aerobar choice, that's a potential conundrum. This will need a rethink if hydration is to seamlessly integrate with bars like these, and bars like these are certainly coming.
