Project Liberty: Cervelo S5 VWD

Project Liberty: Cervelo S5 VWD

What you're looking at here is Liberty: my Cervelo S5 VWD project build that is meant to be an ultra light, highly aerodynamic road bike. This baby is 12.2 lbs as pictured, and is as slippery as anything on the road. It also happens to have the ability to become a complete TT machine with the addition of the aerobar extension hardware, for a weight penalty of just 200 grams more. There's a LOT of custom work going on here, and I'm going to take my time to describe it to you. Not every choice I made on this bike will appeal to every reader, but that's not the point.

The name I chose for this build, Liberty, refers to the fact that it was meant for me, and I exercised complete freedom in choosing how to make it, without concern for the journalistic implications of any eccentric choices I made. From start to finish, the process of building this bike has been extraordinarily fun. This bike really is everything I wanted it to be. At every step of the build, I just did what I thought would be cool; I figured the end result would have journalistic merit anyway, even if I wasn't specifically focused on what that merit was.

Here's a quick video showing off the bike in action:

So, what is this thing, anyway? Well, the original inspiration for the bike was this crazy little number that Trek built up for Chris Lieto back in 2010. Ever since I saw that bike, I'd wanted to make a dedicated road bike, built with an aero base bar and aero brake levers. The primary concept is to forego the traditional drop bars in favor of more aerodynamic ones, while still preserving road-specific geometry. Why? There are a few reasons. First, I rarely use my drops, and figured that swapping the typical ram horns for an aero base bar would yield a pretty huge aerodynamic improvement. Getting the body lower can be accomplished just by leaning down, no drops necessary. And I'm not a sprinter, so I don't have need of that particular position on the bike. The aero base bar would be the perfect starting point for this otherwise decidedly road-specific bike.
Refining the Concept

The first requirement for Liberty was a nude carbon bike. Some people find this look to be a bit weird, but to me it's the most beautiful finish possible. I just love getting to see the raw carbon construction. So we had a professional paint shop strip the bike down. The black Cervelo logo was actually painted on with a stencil, and then clearcoat applied to everything.
Okay, so step one was building a road bike with an aero base bar. After that, it surely follows that we'll want the rest of the bike to be reasonably aerodynamic as well. Let's go with a full aero road frame, aero wheels, the whole deal. Maybe those wheels will be aero but not too deep, because this will be a bike intended for all-conditions riding. Sure, if you wanted to race with this thing, you might pick a different wheelset depending on the course. But this bike is primarily going to be a daily rider, not a race-only purebred. So we'll be looking at something in the 30-45mm range, and there are a lot of great wheels in that category.

But, because I'm a bit of a weight weenie, I'll try to make this thing fiercely light. Despite the penalty that usually comes with aero parts, I'm determined, at the very least, to break the UCI weight barrier of 14.99 lbs (6.8 kg). Careful minimalism in component selection and a little help from my friends at Dash Cycles will help us get there. And because this is going to be MY bike, and I'm being utterly selfish in the direction of this project, I'm going to make sure that virtually everything on the bike is finished in naked carbon fiber. In my opinion, that's the most beautiful paint scheme there is. I especially love it when you can get a frame in nude carbon WITHOUT a cosmetic layer of fabric over the top of everything. I like to see the details, where one layup schedule comes in contact with another, where fabric changes from unidirectional to 3k, and where seams come together from different parts being bonded in. The best way to get this kind of detail is to start with a painted bike, and remove the paint. Manufacturers rarely bother to put a cosmetic layer of carbon on top of their frames if they're going to paint them anyway.

At the end of the day, this this bike is light, stiff, aero, and just a ton of FUN. I'd say the mission was accomplished.

Now, the idea of a road bike with an aero base bar was an easy one to conceptualize, but once you get there, you've got the problem of how to add shifters. On the Lieto bike, linked above, Trek opted to go for a single-speed without shifters. But I wanted a much more usable bike than that. So how do you add shifters to a bike that only accepts aero brake levers? The solution, of course, is Di2 (or Campagnolo EPS). That will let us get this bike shifting beautifully, without needing anything too weird or custom. But of course, this is an all-out build, so (spoiler alert) I ended up making the shifting hardware custom anyway!

I think that's sufficient for an overview of how I came up with the concept for the bike. Hit the jump for how it was all executed, and finally on page three, we'll go over the ride quality of the finished rig, and a review of the Cervelo S5 frame at the heart of the build.