Cervelo's guide to free speed

Jeff Unruh

 http://lavamagazine.com/gear/free-s...z1ZNs5QXgy

Biggest thing I read here that conflicts from what I gathered in the Haus this year is the rear mounted hydration.  Interesting read...

Jenn Edwards

Jeff thanks for posting! This is almost EXACTLY my set up and I was THRILLED with it in my IM and rode to a 5:48:xx split with a 1.03 VI.  How validating especially the part about the rear hydration which I DO use to store my tools and had gotten mixed feedback on.  Now... how can I ditch the bottle on the frame?  Hmmm... good winter project! 

Yay!     

 

• Front: "A standard round bottle mounted horizontally between the rider’s arms, however, was a revelation! It filled in the turbulent area behind the rider’s hands and actually reduced drag. This set-up was not only faster than the vertical bottle, but surprisingly, faster than no bottle at all."
• Rear: "You do want to keep the bottles (and whatever else you have stored with them) as narrow as possible so that the air comes back together quickly after leaving your body. There wasn’t a huge variation in drag depending on the position of the bottles behind the saddle; whether high or low, near or far. Many people use these systems for storage of tires, tubes, and cartridges. This looks to be a good location as long as they don’t stick out and grab air.This data was mostly collected in 2007 with a live rider at 0 degrees of yaw, but if you keep the bottles close to the rider and not too wide the results extend out to higher yaw angles. At any rate, while test results can vary somewhat, the lesson is that bottles behind your saddle do not have a large penalty and, depending on the design, may have a significant advantage. This series of tests is illustrated by CFD simulations we’ve run subsequently, which show that the athlete’s body has a low pressure recirculation zone behind the seat that the bottles appear to fill nicely."
• Frame: "If you use a round bottle on these bikes it is always fastest on the down tube but still adds typically 40-50 grams of drag."
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kurshing

@ Jenn - regarding ditching the water bottle on the frame...easy, there are aid stations every 15 miles; you should be more than fine with 3 of them, especially if you are riding at a good clip like 5:48. Just leave that one for the training rides to avoid stopping so much.

I am with you though...I am relieved to know that Cervelo feels the rear system doesn't create drag because it really is a great thing to have at the long course distance where I am not all that worried about flying mounts (which the rear system makes difficult for me). I am thinking I will switch, full time, to the horizontal bottle (instead of aero bottle) up front, nothing on the frame (was going with one on the down tube), and a rear x-lab set-up. If it is at least not slower, then that rear system makes things a lot easier.

Thanks Jeff!

Brian Quarton [OLD]

Stephen beat me to it with his comments on Jenn's setup. Streamline, don't give back any speed. After a lot of thought I went with an odd setup at IMWI. I carried my flat kit in the Dark Speed Works bento. No frame bottle. To me that defeats the porpose of having an aero frame. I wanted to run a horizontal bottle, but couldn't make it work. Be sure to hide it between your arms, not above. Also was not impressed with data on front end hydration systems or Speedfil with straws, but I went with the NeverReach, also called the NeverHeardOfIt. The hose runs horizontally on the top tube, not vertically (bad). Have to keep the straw out of the wind. The fishbowl holds 72 ounces. My bike splits were good last year, but hopefully that is better fitness too. This setup wasn't perfect. I had to keep the fishbowl filled. At aid stations I had to empty bottles into it quickly, nearly impossible. Next time I would just go with a bottle between the aerobars only, I have a Vision DrinkMore. Getting out of aero to drink was found to be a negligable penalty. Much simplier. But most importantly it is faster than not having it. Lastly Cervelo did not do this to be helpful, they did it for business, as you can bet a competitor is working on something glitzy.

Jeff Unruh

I am too oldschool with a aero drink and bottle on the seat tube -- I was told better there than down tube on my Kuota K-Factor. Water in the Aero and nutrition in the seat tube bottle. Bento box for tools.

Paul Hough

I only use frame bottles in training. My Giant Advanced Trinity SL-1 doesn't even have frame mounts. I use a torpedo bottle up front and an XLAB in the back (one cage for hydration and the other for tubes/tools. For my QR CD0.1 I use the same rear set up but have a Torhans Aero Bottle...not tested by Cervelo in their study. The straw is encased in an aero sleeve and the system has been tunnel tested as better than a torpedo set up. However, I like that Cervelo tested with an actual rider (or dummy) and agree with them that it is the most accurate method.

bkcomiskey

That coincided with the tri-sports 20% off sale. xlab topedo mount on the way.

Jeff Unruh

Oh yeah - forgot about that sale at TriSports - time to support the economy...

William Jenks

Zip ties! very cheap!

Coach Patrick

I am running a torpedo and rear mount system for Kona...kinda light weight in the rear so it's lower and the bottle protrude a bit..but I got me some hips so it's all right. No bottle on the downtube. Pics forthcoming from the island.