Friday, March 8, 2013

Do you do a watt-a saving?

Hehe, get it? So punny.

On the eve of the first multi-sport race of the year (for me) I think it's important to go over some easy ways to buy speed.  Or, if not purchase, to make conscious decisions to reduce one's aero impact.  I've often heard it described as "punching as small a hole through the air as possible" and I really like that.

Let's start from the front and work our way back, shall we?

So this first picture is of the front of my P3.  The thing that stands out the most is how little "crap" there is visible.  Visible to the eye, or visible to the wind (hopefully).  A clean front profile can save a good bit of demand watts.

So in terms of aftermarket purchases, the TriRig Omega brake is obviously the most "important" in this picture.  What's also a bit more subtle is the tire/rim interaction.  The tire is the exact width of the rim (to a degree) and this complements an improvement in aerodynamics.  Tire width can be just as important as tire choice.  To a degree, again. Another change in this picture is the cable routing.  The rear brake housing, despite entering on the top tube, is invisible to the wind as it has been routed above and around the stem.  The front and rear shift housings are routed externally (i.e. not through the 3T Aura extensions) and this allows them to stay closer to the top tube, which means they're very slightly less "awkward" looking in the front profile.  Ideally, I'd like them to be even closer but it's just about as "perfect" as it can get.

Another thing that many forget when using Zipp wheels is that the hub features an "aero" component.  So the idea is you put your wheel into the fork then rotate the hub adjustment "piece" so that it is in its "aero" position, then tighten the quick release. The main "purchased" speed you see here is obviously the Zipp front wheel.  I personally prefer the carbon clincher (as opposed to the tubular version) for a number of reasons...

1) Tire selection is as good for clinchers as it is for tubulars, if not better
2) Installation and in-race fixing is much, much easier
3) Achieving "ideal" rolling resistance is easy because by simply installing your chosen tire with a latex tube you do the job.  With tubulars to achieve "ideal" RR you must clean the rim of all existing  dried glue (extremely difficult).  You must then put several layers of glue on both the tube and the tire to really get the tire tight to the rim.  This makes any removal or repair very difficult.
4) Fixing a flat is generally cheaper ($15 latex tube/$8 butyl tube vs. $90-120 tubular tire)

The ONLY downside in my opinion is that the carbon clincher version of these wheels are more expensive.

An often overlooked part of aerodynamics and tri bikes: saddle comfort.  If you wiggle around a lot and/or get out of your saddle a lot (due to discomfort) then you are not as aero as if you are firmly (and comfortably) planted on your butt in the saddle.  Now, a saddle like this is obviously very ridiculous.  Of any component on this bike it, without a doubt, elicits the most questions and comments.  It is incredibly expensive.  It is incredibly odd-looking.  But wow is it comfortable.  I often ask people when they bemoan saddle expense ($150-200 saddle options): "How much are you willing to pay for a comfortable undercarriage."  The answer is almost always a begrudging: "Whatever."

Ultimately position plays the biggest role.  Buying free speed (yes, I realize that's paradoxical) starts with the big stuff and gets into the more nit-picky stuff:

Cockpit (basebar + extensions)

There are more options available to "aero" out your bike but those stand out as the ''easiest."  Most people could probably do helmet, tires, tubes and a wheelcover and that would gain them many minutes over an IM.  Once you start trying to max out the potential of your bike it becomes a less awesome dollar per watt spending program.

The only good place for Tim Noakes' novel (just kidding, sort of)
Overall, I like knowing that if I have 250 watts for a race that I'm making the most use out of those 250 watts.  I don't like the idea of "wasting'' speed.  It's one of the reasons I ride Cervelo.  It's one of the reasons I ride Zipps.  Trust in your product choice. Many people do not or don't know enough to even ask the right questions. Gotta get that eduhmacation!

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