In time trialing, the most important aspect of aerodynamics is rider position, not the aero qualities of the bike. Teardrop-shaped down tubes and seatposts make a difference, but it isn’t significant compared to your furiously pumping legs and wind-catching chest.
As a result, a road bike fitted with aero bars and set up so the rider is in an optimum position is nearly as good as a dedicated time trial machine.
Time trial bikes do have one advantage: They’re designed to make getting an aero position easier. They usually have steeper seat-tube angles and a handlebar much lower than the saddle. But if you move the saddle forward on your road bike and use a stem that allows you to lower the bar, you can come pretty close.
We started this 2-part series last week and will finish today with more tips on maximizing your road bike – and your ability to ride it – as a TT machine.
Consider aerodynamic wheels. Every wheel manufacturer, and plenty of magazine articles, will tell you how many seconds a specific set of wheels can save in a 40K time trial. Take all these numbers with a large grain of salt. But there’s no question that aero wheels can save substantial time compared to conventional wheels.
On flat courses I use a Mavic disk rear wheel that I received as part of our 1996 Race Across America sponsorship. It’s especially good in crosswinds. The theory is that its lenticular shape acts like a sail and allows the wind coming from the side to push the bike forward. I don’t know if that’s valid physics, but it seems to work that way when I’m riding the wheel.
The disk is heavier than a spoked wheel, so on hilly courses I use the other sponsorship rear wheel, a Mavic Cosmic with a carbon rim and 16 bladed spokes. Regardless of which rear wheel I use, I run a Mavic Cosmic with 16 radially laced spokes on the front.
Of course, there are plenty of other good wheel choices available. But I have an emotional attachment to these wheels because I rode them across the U.S. when our RAAM team set the senior 50+ record of 5 days, 11 hours, 21 minutes. I also used the disk/Cosmic combination to win the Colorado Masters TT and get a bronze medal at Masters Nationals.
Use an aero helmet. You have plenty of choices nowadays other than the old-school teardrop models. Many normal road helmets come with snap-on plastic covers to effectively make them aero lids. Others have full-time aero properties. Because there are so many choices, it really makes it easy to find one that works well for you.
Take offbottle cages. It’s hard to drink from a bottle during a race, so remove the cages. Their wind resistance is negligible but the bike looks faster without them and that’s worth a few seconds in psychological boost — if nothing else.
Use an appropriate cassette. I often time trial with an 11-21 cassette. Does that mean I can push a 53×11-tooth gear on the flat? Nope — not even close. But on downhill sections or with the sort of tailwind we often get in Colorado — when small cows are likely to be blown over — the 11 lets me coax a bit more speed. Of course, many of us ride compacts these days, so you may be better able to spin up that 11-tooth cog with your 50-tooth ring.
Think about your low gear, too. If the course is flat to rolling, you don’t need a 25-tooth big cog. Some riders like to run an 11-23 on rolling courses because they can stay in the big ring on gradual uphills using the 53×21. (If you ride a compact crank, you’ll simply need to align your gearing accordingly.) Because shifting the front derailleur is more time-consuming and potentially problematic, they’d rather carry the larger rear cog to be able to use the big ring exclusively during the race.
Consider a skin suit. Snug-fitting, one-piece time trialing suits are significantly more aerodynamic than shorts and a jersey. They don’t have the wind-catching wrinkles, folds of material and pockets that jerseys do.
Crumple your number. When you get your race number, crumple it into a ball, then flatten it and pin it on. The crumpling takes the stiffness out of the material and helps the number conform to your body. Uncrumpled numbers tend to flap, rattle and catch more wind, slowing you down.
You might also choose spray glue that some riders prefer. In that case, the crumpling would probably do more harm than good.