Springing for a tri-specific bike? Here are some guidelines

By Jay Prasuhn and Dave Bittenburg Triathlete magazine

It's time to get off that old nag, the hand-me-down road bike from the late '80s and get onto a slammed forward, take-no-prisoners tri-specific bike. Grrr! But do you know what to look for?

Tri-specific bike models have been built by numerous makers. Shops that carry triathlon-specific bikes (not all bike shops do, so look around) might stock models by Cannondale, Quintana Roo, Litespeed, Kestrel, Trek, Softride, Cervelo, Aegis, and/or many others.

What material do you want to ride on? And what's the difference between Ultegra and Dura-Ace anyway? Fear not, we answer the questions you're apt to ask when perusing the newest tri bikes at your local shop.

Following are seven of the most commonly asked questions posed in a tri bike shop:

1. What's the importance of a steep seat tube angle?

It is a generally accepted fact that the seat tube (the main tube your seat post sets into) on a triathlon bike should be placed more upright and forward than a road bike's relatively slack positioning.

The reason is that the forward position places the rider over the cranks further and puts him/her in an aerodynamically sleek position. The position also saves key muscles for running. Road bike seat tube geometry is geared toward making efficient use of all leg muscles, especially the hamstrings, which is an important muscle to save for the run. Tri-geometry makes more use of the quads to generate power.

2. My friend said material X makes the best bike frame material. What's the difference?

The bike-frame material to lean toward depends on what distance events you plan on doing, how heavy you are and how much you plan to ride. First, let's break down each of the industry's main materials: aluminum, steel, carbon fiber, and titanium.

Aluminum: It's what most of the bikes out there are made from. Why? It's light and stiff, inherently the stiffest bike frame material on the market. As such, guys who love to sprint out of corners worship it, as the frame doesn't flex much in the bottom bracket area under the torque applied by gear mashing. All applied power is transferred to the wheel for forward motion. The drawback is that the stiffness will wear down on long rides, particularly on pitted roads. Heavier (175+ pounds) cyclists love it, but lightweights are often shaken to tears on long rides on bad roads. It's a great sprint or Olympic distance steed, and is still quite nice on smooth, newly paved roads, like the Queen K.

Steel: The trusty standard of the '50s is still seen by many as the best frame material. And in many ways it is. The advantages: It offers a frame shock absorbency that makes it a comfortable material for the long rides of Ironman distance, and it's lively out of the saddle. Disadvantages: It's still regarded as heavy (by only a pound or two in most cases), especially against aluminum and carbon fiber.

Carbon fiber: This is the comfort special, a Godsend for guys with bad backs. As the "softest" material out there, it has the best shock absorbency and makes for a great long-distance event bike. The negative to it is the flex that saves your body fatigue always tends to take power away when you get out of the saddle. It's still stiff, but it's certainly not steel, titanium or aluminum. It's a great bike for lightweight riders and athletes with aches and pains.

Titanium: Ti is a highly regarded material, and some of today's titanium bikes are destined to be heirlooms. It offers a ride quality very much that of steel, but at less weight. It's absorbent on chattery roads, but conversely is very stiff out of the saddle. It's also super durable. The best of all worlds, and guys of any weight can glean its benefits. The disadvantage? Cost. It's not called unobtanium for nothing. Titanium is not what makes it expensive, but rather the processing of the metal.

Beam bikes: Two companies, Softride and Titanflex, hold court in this unique category. Their aluminum bikes are built under a carbon fiber or aluminum beam (and titanium in Titanflex's case) that flexes, absorbing road shock. As such, it's stiff out of the saddle and comfy in it. These bikes are another favorite of athletes with bad backs.

3. What is a group and why is it important?

The group is the package of components that accompanies a bike, consisting of shifters, brakes, derailleurs _ all the shiny stuff that hangs off the frame. Two companies have the market cornered here, Shimano and Campagnolo. Both are established and very reliable. Each company has put together a hierarchy of component groups that get lighter and perform cleaner as you go up the price chart. Campy (as it's affectively known), a classic Italian manufacturer, has five groups (top-of-the-line Record, Chorus, Daytona, Veloce and Mirage), but tri-bikes typically feature only the top two, Record and Chorus. Their stuff is known for being very durable. In the past, it has been known to be a bit heavy, but that is rapidly changing.

You'll find Shimano, however, on 90 percent of the bikes out there. Their hierarchical breakdown, from race-specific to entry level, reads: Dura-Ace, Ultegra, 105, Tiagra, and Sora, with the top four being found on tri bikes.

4. What's up with that fat, strange-shaped tubing?

For the most part, unless you average 28 mph, the bladed down tubes serve only to make the bike stiffer, not to provide a huge aero advantage. There is a decrease in wind resistance at speeds of 21 mph or so, but the benefits are very minimal. You can cut most of your time with the proper aero position on your bike and by investing in deep-dish aero wheels.

5. How important is the fork?

Critical. You'll find most are carbon fiber (the softest, most shock absorbent material), which is what you want when a lot of your time on the bike is spent over the bike's front end in the aerobars. If you look down while riding on a pitted section of the road, you can see the fork blades actually flexing, deflecting the focus of the shock forward on the tire and wheel instead of up into the bike and the rider.

6. What's the difference between a 650c and a 700c wheel?

Not much. Proponents on both sides have said that either creates less rolling resistance, and 650c lovers contend that the wheels have less frontal wind-catching area. Debatable, still. All told, the big boys (6 foot and up) are more stable on 700c wheels, and smaller guys and women are often set up nicely on 650c wheels.

7. Do they have these bikes at Costco?

Not a chance. Tri bikes are somewhat of a specialty item, so pick up the phone book and go to as many bike shops in your area as you can. Check out the shop. See how many tri bikes, accessories and clothes they deal and stock. Ask questions. See if they have a triathlete working who can answer tri bike questions. In most reputable shops, when you buy a bike, you've also purchased the service and experience of the sales staff. If they don't show immediate interest in talking to you and ask specifics about what you're looking for, move along.

Alright, you have the basics. Remember that all of the major players have a Web site. Check them out to get more information on how their bikes are made, the company's philosophy and reputation. Don't forget to take catalogues of the bikes you're interested in home and pore over them, comparing frame design, kit options and prices.