How to Choose Your Next Tri Bike: An Engineer’s Guide (Step 2)

In Part 1 of this series on how to pick your next tri bike, I began a discussion of how to approach buying your “ultimate” bike. Just to review, the eight steps of our process are:

1. Define your goals
2. Assess your own performance
3. Narrow the choices by price and fit
4. Find the manufacturers’ white papers
5. Look for independent research and reviews
6. Get a test ride and weight measurement
7. Compare aerodyamic data
8. Weigh the intangibles and make a final decision

In Step 1, we covered goal setting and the self-assessment. So let’s continue with Step 2.

Narrow the choices by price and fit

Now we get to the fun part– looking at new bikes! You’re certain to have your eye on a few. Everyone has their dream ride. Go ahead and get a good fit at your local bike shop, preferably with a Retul or F.I.S.T. certified staff. Also check ahead of time to see what bikes you’re most interested in and familiarize yourself with their fitting ranges. It will be helpful to know what standard of measurement they use. Most manufacturers use stack and reach. Dan Empfield, the founder of Quintana Roo and the website also is the expert who invented the “FIST” bike fit method. He  wrote a good educational piece on bike fit that also shows some brand-specific comparisons here. It may be a little technical for those who haven’t studied up on how bike fit methods work, but the graphical comparison and discussion demonstrate that not all bikes are built the same. Bike manufacturers disagree not just on design for the best ride, but also they even disagree on how bikes should fit riders. That’s why this is such an important component of the decision process.

Photo courtesy trib

It’s pretty easy to eliminate candidate bikes based on how they fit. As you check your fit on potential bikes, ask these questions:

  • How long are the crank arms?
  • What about the aerobars?
  • Is the saddle already on it the one you want to ride?
  • Are you thinking about upgrading wheels at the same time as the bike?

The bike on the floor is most likely not the bike you want. It will require adjustments to make it your own, and those adjustments will add to the price. Perhaps you’ll take some parts off your current ride to make it more comfortable for yourself (an especially good idea, since “parting out” a bike often gets you more money than selling a complete bike on sites like E-Bay). If your fit tells you that the current cranks you’re riding are less than ideal for your optimal position, you may be going a few hundred dollars into the hole for new ones. And unless you’re an avid do-it-yourselfer, there’s a shop fee for making the exchange. Know what the whole bike will cost before you pull out your credit card. If the whole cost is outside your price range, cut that bike from your list of contenders.

Find the manufacturers’ white papers

Now we get to the real homework. It’s a standard practice these days for manufacturers to publish white papers touting the technological specifications of their bikes. Of course, each paper says their bike is the best, so it’s a little difficult to tell who is presenting the most accurate data. The key to using white papers to inform your purchasing decision is to avoid relying on just one paper. To make the best use of them, you should take advantage of the comparative aspect of these papers. Most manufacturers tend to throw their bike in the wind tunnel and compare it to others. Because wind tunnel time is expensive, they don’t always compare the same bikes. But depending on who they believe their top competitors are and whose bikes are selling well, most manufacturers tend to test against the same models. This is where you benefit.

Let’s say you’ve narrowed your choice down to bikes “A” and “B.” A’s white paper claims that it’s more aerodynamic than B and vice versa. Who can you trust? Why not consult the white papers for C, D, E, and F? Look for enough reports, and you’ll find a few that test A, a few that test B, and maybe even one that runs a comparison between A and B. Again, each of them will say their bike is better, but based on your other criteria you’ve already narrowed your interest to A and B.

What you want to look for in those papers isn’t better numbers, but consistent numbers. Manufacturers are often quick to point out that wind tunnel tests are not comparable, and that is somewhat true. Tunnels come in different sizes and shapes and use different methods to measure drag. Also, due to their different geographic locations, the atmospheric conditions can influence results. However, these differences are often exaggerated. After all, if wind tunnel test results were so different they couldn’t be considered reliable then bike manufacturers wouldn’t use them to develop their bikes in the first place. So, despite the small differences that may exist, you can still make your “best guess” better by checking various tests on the same bike. If a certain set of numbers looks pretty consistent and another white paper claims that the bike performed particularly better or worse, you can probably throw out the outlier and feel more confident in the “majority vote.” We’ll discuss how to conduct your assessment of those numbers in Part 3.

Look for independent reviews and research

Ride reviews that discuss a bike’s “stiffness” and “handling” are only of marginal value. They probably tell you more about the reviewer’s personal tastes in bikes than the bike itself. However, there are some good points to look out for. A savvy cycling  tech writer will look carefully at a bike’s construction and quickly spot nuances you may or may not discover until after you’ve owned it for a while. This can be especially helpful regarding new triathlon bike designs due to innovations in brake placement and integration of the fork and head set. Are you going to need tweezers to change your brake pads? Does the seat tube cutout for the rear wheel prevent you from using your preferred tire size? Will it take your local mechanic a week to replace a snapped brake cable due to the crazy internal routing? These are all considerations that a good reviewer will pick up on. Additionally, a few European publications invest the money in conducting lab tests on select bikes, to include stress tests on frame strength and even wind tunnel assessments of aerodynamic performance. Tour, published in Germany, is especially thorough in their tests (they even examine wheels from time to time). The results are difficult to get in English, but with a little creative internet searching and online translation you might be able to get some interesting data. Tour typically focuses on road bikes, but it’s worth paying attention in case. Both Velo and Bicycling magazines have also independently tested bikes in the wind tunnel. Again, they remain focused on road bikes, but for those athletes looking for an ITU-legal bike, this can still be valuable.

Research is just like training. Staying determined and refusing to quit when you don’t get the results you’re looking for on the first try are the keys to success. Keep at it, be creative in your online search terms, and you may be surprised at just how much information is out there.

In the next installment, we’ll talk about how to read wind tunnel data.

If you’re interested in getting faster, you’ll be fascinated by FASTER: Demystifying the Science of Triathlon Speed. In Faster, astronautical engineer and triathlon journalist Jim Gourley explores the science of triathlon to see what truly makes you faster—and busts the myths and doublespeak that waste your money and slow down your racing. With this knowledge on your side, you can make simple changes that add up to free speed and faster racing.