So I Bought a Tri Bike
For a couple of years I've been content racing triathlons with my road bike (with clip-on aero bars and forward seat post). I knew that a tri bike would likely shave 5ish minutes off my bike split (on an Olympic distance course), and that it would help with my run (by not burning up my quads as much). But I put it off, wanting to work on my swim and run, which are by far my weaker sports. Even a few months ago I was convinced it would be at least another year before I bought one.
Over the past month, a couple of things changed. First, I've made big progress with my swimming. Second, on tempo rides with friends I couldn't keep up on my road bike when heading into the wind unless I drafted (which was annoying, because then we couldn't chat (hour-long steady-paced tempo rides can be a bit tedious without some socializing...)). Third, it was pointed out, "Brian, guys are beating you who shouldn't be." It might have been this last comment that mattered the most...
Is it Sleek and Sexy?
I did an amazingly little amount of research into bikes before I bought one--except for this: I knew that a proper fit is one of the most important factors in both being aero (going fast) and comfortable (able to stay aero the whole race). So before I even looked at bikes, I went to the local bike shop and paid to get measured on a "fit bike".
A fit bike is basically a spin bike with readily adjustable components that vary the seat height, arm rest height, arm rest reach, and position of the saddle fore & aft in relation to the pedals. Over the course of 3+ hours we experimented with a bunch of different positions to see what felt most comfortable. This bike is also hooked to a power meter, so it was easy to see if a position was causing me to lose power or not.
Through the fit process, I kept asking to be rotated forward (steeper seat angle) and down (flatter back, more aero). It was interesting to feel the difference in which leg muscles I was using as we progressed through positions. Starting back at what felt similar to a road bike positon, most of my power was coming from my quads. The steeper the seat angle, however, the more I was using my hamstrings and the less I was using my quads. In particular, I felt a huge relief in the vastus lateralis, which is the largest quad muscle and the one that makes the bump above your knee on the outer side of the leg. This "saving the quads" for the run is the second huge reason (in addition to being more aero) that a tri bike helps so much.
So after we took all of those measurements, we compared them to the available bikes. I was at a quite steep seat angle (80 degrees), which limited the choices (a lot of tri bike seem to max out at around 78 degrees). The Felt bikes fit me, and we figured out a package that met my needs (Ultegra drivetrain) and budget. I ended up with the Felt B-12, and call it the vitamin bike.
Which is all a very roundabout way of answering the question: Yes, it is sleek and sexy.
But is it Fast?
I had been warned against just jumping on and letting it rip--with such a radically different body position than I'm used to, I need to accustom my hamstrings to suddenly doing a lot more work. On my second ride I went for a zone 3 tempo spin around Fiesta Island. The island has a flat, 4-mile loop with minimal traffic and no stop signs--it's ideal for time trialing and holding a sustained effort. When I'm in Base Endurance training, a 50-70 minute tempo ride on Fiesta is a weekly occurrence, so I have a lot of data to compare to.
So I went out and rode two laps at a zone 3 tempo pace, and then came home and found a comparable ride from my road bike. Here's the comparison between the two: What this boils down to: at 220 watts on my road bike I averaged 20.5 mph; at 220 watts on the tri bike I averaged 22.2 mph. If those were race speeds on an Olympic distance course, that would be 1:13 minutes versus 1:07.5 minutes. In other words, over five minutes saved!
A Few Caveats
A few caveats are in order. First, these rides were done on different days. It's likely the wind conditions were different. On the Felt, the wind was a moderate breeze. On the road bike on May 28, I'm guessing the wind speeds were similar based on the average speed (on a very windy day on my road bike my average speeds are 20.0 at a tempo pace). Notice the minimum speeds though--15.8 for the road bike, 18.1 for the tri bike. These were obviously taken when heading into the wind--and this is where a tri bike will excel with its greater aero position. Note that the maximum speeds (with a tailwind) are not that much different.
A second caveat is that after 20 minutes my hamstrings were really tired! With the idea of easing into the bike, I called it a day. I'll gradually build up my tempo times on this bike to make it easy on those muscles.
A third caveat is that my heart rate was a bit high. I don't have great data from my road bike, but it seems that my heart rate was generally in the 158-162 range. On the tri bike, it averaged 165. Heart rates can vary a good bit from day to day, and are especially influenced by fatigue from prior days, the amount of sleep the night before, stress, etc. But I suspect it was high for two reasons. First, I'm using new muscles that need to get into shape. Just like my heart rate is elevated for a few weeks when resuming running after an extended break, I suspect it will be higher until I get used to this bike. Also, by also using my hamstrings, I'm using a larger muscle mass than just my quads--it's possible that's demanding more blood flow.
Yes, It's Fast!
I want to be clear that the speed I've gained is largely because I'm in a very aero position that allows me to generate good power. This is a result of the careful fit process, and finding a bike that fits my body's geometry. So this isn't inherently an endorsement of the Felt. Yes, it's a fine bike, and I'm very happy with it so far. But there are at least a half-dozen other bikes on the market that are just as nice, and would likely be just as fast for the people whose bodies/riding styles fit them.
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