The rear rack

I’ve received a number of e-mails and questions about my rear hydration/rack system on my tri bike.  So this is just a quick post to explain the various components.  The reason some have asked is that the Cervelo’s P2C’s are a bit tricky in that they don’t have an easily mountable location due to the aero seat post, hence some of the additional confusion.  See below for what I mean – there’s no place to install a normal mount system.

IMG_8900 1280 x 853

As a random disclaimer – I don’t have any connection to any of the below products other than simply swiping my credit card and attaching them to my bike (cause that’s about the only bike maintenance I’m actually successful at).

The Rear Mount Core System:

The core of the mount system is the Hydrotrail H.5 – which is about $50 at most online retailers, or directly through their site.

The mount kit comes with all the screws required, as well as the nifty strap-on system (yes, you didn’t think I’d be able to get that word in there, did ya?).  You can see the two straps here (one undone), that allow you to strap on the spare tube/tire.

IMG_8916 1280 x 853

Water Bottle Cages

It doesn’t come with any water bottle cages through, so you’ll need to add two of your own.  I randomly choose some Tacx ones that are made of flexible rubber.  There were simply what was on the top shelf of my nearby tri store.

I know many folks worry about popping bottles off the back of their bikes.  I’ve rode somewhere north of 1,000 miles with this setup outside in the past couple of months, and I have only popped one bottle off the system.

And to be fair – it was the nastiest pothole out there.  In fact, it actually bent my entire seat downwards at a 45* angle upon hitting it.  And when the bottle went flying – it was because it SNAPPED the water bottle cage.  Seriously, it snapped it due to the forces exerted from the water in the bottle and the pothole.  All during a race…

IMG_8903 640 x 960

The system holds two water bottles, one on either side.

IMG_8025 1280 x 853

The CO2/tool bag system:

Last up is the most critical piece – my little tool/CO2 bag.  I grabbed the baggie from this system, and then tossed the contents, as I prefer a nozzle that allows you to stop/start flow as needed.  (Btw, if you didn’t see my post on how to use CO2, now would be a good time).  In the bag I have two CO2 cartridges, one CO2 nozzle, one tire iron (you don’t need many for tubular’s), and one wrench set.  That’s it.

IMG_8910 1280 x 853

From there I took a little zip tie and made a small loop.  I then strung that loop through the upper Velcro strap.  This keeps it from going anywhere in the event it somehow falls through – although with the zip tie/Velcro it makes going anywhere or falling through impossible, as it holds it perfectly in place.

IMG_8905 1280 x 853

After that, I just slide it in the slot (see two photos above) and then tighten the Velcro.  It fits absolutely perfectly and doesn’t go anywhere.

That’s it – nice, clean and simple.

IMG_8023 1280 x 853


Hopefully, you found this post useful. The website is really a labor of love, so please consider becoming a DC RAINMAKER Supporter. This gets you an ad-free experience, and access to our (mostly) bi-monthly behind-the-scenes video series of “Shed Talkin’”.

Support DCRainMaker - Shop on Amazon

Otherwise, perhaps consider using the below link if shopping on Amazon. As an Amazon Associate, I earn from qualifying purchases. It doesn’t cost you anything extra, but your purchases help support this website a lot. It could simply be buying toilet paper, or this pizza oven we use and love.


Post a Comment

Your email address will not be published. Required fields are marked.
If you would like a profile picture, simply register at Gravatar, which works here on DCR and across the web.

Click here to Subscribe without commenting

Add a picture



  1. Only popped on one water bottle… lucky you! In the past 7 weeks I have popped about 5 water bottle out of my rear seat hydration systen!

  2. I guess this is really only pertinent to people doing IMs? I seem to do okay having my hydration up front with the Profile Design aero bottle and the one water bottle on the down tube (we have the same bike :)).

    I guess I’m paranoid about that rear bottle system being knocked out because I’ve seen it happen waaaay too much!

    However, I do like the idea of having my tools back there because right now I’m using my Bento Box for tools and that is annoying.

    Thanks for the in-depth coverage!

  3. Friends of mine who have the same bike have the same water bottle mount system. I think they paid more though!

  4. THANK YOU SO MUCH FOR THE PICTURES! I have a Hydro tail as well and mine was one of the first carbon designs. It did not come with those nifty velcro wraps to hold a tube. I will make my way to the LBS and see if they can help me out on that one. I have been putting all of my tube/tool/cartridge stuff in an old mini-Giant (HA! Oxymoron!) saddle bag and velcro strapping it into one of the Hydro-tail water bottle cages.

  5. SLB

    Very slick rig, well worth considering for our sunny climbs here, another triple digit weekend is forcast…roll on winter!