There are many types of nice wheels on the market. This article is not going to touch on those types. Instead, I am only going to cover a few of the great & more popular models. So if I just happen to leave your particular favorite out, Don't worry, this is not intended to be a review. I simply picked a few of the top manufacturers and I will discuss some the fundamental basics of aerodynamics in each. Every model wheel here is appropriate for triathlon. So if your in the market for an upgrade..... then check these out! First, let's cover some of the technical basics. Aerodynamics is the study of how a solid body moves through the air which surrounds it. So when I compare this definition to the sport of cycling, it's about how a rider and bike together overcome the air resistance created by forward motion. In rotational motion, the moment of inertia is directly affected by the amount of mass or weight. Inertia is the natural tendancy of an object to remain at rest or in motion at a constant speed in a straight line or axis. Lowering the moment of inertia and the wheels rotational weight means less resistance to forward motion. This translates to faster acceleration and better performance. Next, The speed you can achieve on your bike is determined by two factors. The first is how much power you are able to produce, measured in watts. The second is the wind resistance this creates, commonly referred to as "drag" in wind tunnel testing. The faster you go, the more of this drag there is to overcome. This is why a rider with a technical advantage is often able to defeat one with a greater power output. So that said, Take advantage of every second you can get because they all add up. Here are a few more technical facts about you and your machine. Approximately 80% of an average rider's output is used to overcome the effects of frame & rider drag when cycling on flat terrain. Any reduction in this percentage will therefore result in either an increase in speed or a decrease in the effort required to maintain it. Wheel drag can account for over 10% of your energy on the bike split alone. A front aero wheel can save over one minute in a 40k bike leg. Steve Hed of HED Cycle Wheels said: "It's a relatively simple matter to correctly design an aero wheel capable of producing a low drag factor against a direct headwind. However, we understand that a true headwind is virtually unknown in nature as it relates to cycling aerodynamics. All it takes is a 5mm lateral shift by the rider and the headwind becomes a side wind in relation to the front wheel. Designing a wheel that performs correctly in such a situation is therefore paramount. This is why all of our wheels are designed and tested using wind angles from 5 to 20 degrees. By carefully regulating the size and shape of the side section of our wheels, we can achieve optimum wheel performance no matter what the wind conditions happen to be. So when we go faster in the wind tunnel, you go faster out on the road." The Wheels.......... 1) Corima wheels are hand fabricated with the same attention to detail as their frames. One of Corima's technical breakthroughs is the use of a structural foam to reinforce their structures. This allows the opposite carbon walls to work together, improving the distribution of stresses and obtaining a more rigid product at a lower weight than their competitors. Corima wheels also use large diameter ball bearings with water repellant grease and non-friction seals for very low rolling resistance. -12 spoke tubular carbon front or rear with aero bladed stainless steel spokes and hidden nipples for improved aerodynamics. 650c Tubular front 635g, 700c Tubular front 675g. 24 spoke rear is extremely stiff with excellent power transfer and same bladed spokes and hidden nipples. 650c Tubular rear 816g, 700c Tubular rear 856g. Rim depth 40mm on 650, and 45mm on 700. (Tubular 650c pair 1451g, Tubular 700c pair 1531g.) Offered in both clincher and tubular versions. Front clincher: $563.00, front tubular: $475.00, rear clincher: $626.00, rear tubular: $549.00 -4 spoke tubular carbon front or rear with 4 aerodynamically shaped carbon fiber blades. Incredible lateral rigidity. Carbon Rim itself only weighs 240g. So well balanced that it will spin independantly in the front/side eliminating the "egg beater" effect found in other wheels. Rim depth 36mm on 650 and 700c. I recommend using the 12 spoke front and 4 spoke carbon rear combiation more all ideal race day conditions. 650c front 822g , rear 968g (pair=1790g), 700c front 762g, rear 908g (pair=1670g). Note: Use Corima special ceramic brake pads for increased stopping power. Front clincher: $719.00, front tubular: $599.00, rear clincher: $819.00, rear tubular: $699.00, Rear clincher disc: $819.00, rear tubular disc: $719.00 2) HED wheels. I really like their range of choices, you get variety and the ability to mix and match. Common technical design features in all HED wheels, include radially laced aero bladed spokes on front wheels, and non-drive side rear wheels to improve aerodynamics and reduce weight. All wheels have aluminum braking surfaces (clincher & tubular). The hub used in all our HED wheels, is the aerodynamic Sonic hub designed by Hed. -HED 3 spoke carbon has similar aerodynamic efficiency the Deep, but the advantage is that its handling properties are closer to the CX. Suitable for a wide variety of uses including road race, time trial, and triathlon. Three airfoil carbon blades and 55 mm deep rim. Aluminum rim for braking. I recommend this for the rear wheel with a Jet 2000 frontset up, or can be used front and rear on 650c triathlon bikes. Front clincher & tubular: $370.00, rear clincher & tubular: $430.00 -Jet 2000 DEEP features aerodynamic Sonic hubs and a super deep 90mm carbon rim. Almost as efficient as a disc wheel in head winds. (Note: Legal for Hawaii Ironman.) 650c has 18 front spokes, 24 rear. 700c has 24 front spokes, 28 rear. Front clincher & tubular: $318.00, rear clincher: $410.00, rear tubular: $388.00 -Jet 2000 CX with structural carbon fiber, offers great value but now has a 20% lighter aluminum rim. Custom full length spokes have hidden nipples. Aero Sonic hubs. Smooth carbon fairing increases hoop strength by up to 300%. I recommend this used for the front with a Jet 2000 Deep at the rear, or front and rear for both 650c & 700c triathlon bikes. Front clincher & tubular: $300.00, rear clincher & tubular: $360.00 3) Spinergy wheels have long been a popular choice for triathletes due to their style, affordability and durability. Its tri tension design reduces vibration and shock, thus, reducing your fatigue and permitting you to ride longer and faster. Is'nt that what we all want. -Spinergy SPOX R1 wheel uses lightweight, vectran carbon fiber spokes that have 5 times the tensile strength of steel with more vibration damping, less weight and a longer fatigue life. Also, this wheelset has an incredible low moment of inertia design, with the weight centered at the oversized carbon hub. Rember the tech stuff from above? This translates into a wheel with a very low rotating weight giving faster accelerations and help in those tough climbs. The SPOX are available with black or blue rims, and black and yellow spokes. R1: $675.00/pair, R2: $459.00/pair -Spinergy REV-X features 8 flat bladed carbon fiber spokes with an aluminum braking surface and an intergral aluminum hub featuring pressed in sealed bearing cartridges. 700c front tubular 860g, 700c rear tubular 1040g. Rim depth 47mm (700c pair 1900g). $649.00/pair 4) Zipp carbon fiber aerospace technology is legendary. The end result are wheels perfect for both short coarse and long coarse triathlons. Their assortment of different wheels equally dampen harsh road shock and exhibit great strength, climbing and acceleration characteristics. -Zipp 404's deep carbon fiber rim features a new lay up design to increase the wheels lateral stiffness with newly styled straight pull hubs and ovalized stainless steel or titanium spokes to handle very high tension. With a 58mm cross section and gentle convex wall curvature the aerodynamic performance and ride quality is unsurpasssed. $999.00/pair -Zipp 909's are even deeper with the same features as the 404's above make these wheels a very light and aerodynamically efficient combination. The front 650c wheels are 16 spoke, while the 700c wheels are 18 spoke, with deep 68mm carbon rims. Use these as a perfect matching set or pair up the deep section front 909 with a Zipp full carbon Disc on the rear for a super fast combonation. (Note: I don't recommend this setup in high cross wind race conditions.) $1249.99/pair. Rear disc: $ See Dealer... So there you have it....Choose your aerodynamic weapons carefully. If your going to buy just one one wheel, Purchase the front wheel first! It offers the most time savings because it contacts undisturbed clean air. ê