Easton EC 90 TT Tubular wheels; Easton has increased the deep rim profile from 56mm to 90mm for the new EC 90 TT. The Easton claims that the new narrow flange R4TT front hub, which reduces frontal, spoke area by 50%. The new EC90TT displays lower drag than the Zipp 808 at 0, 5, 10, 15 and 20 degree yaw angles.

The set weights 1440g, 30 grams lighter than the Zipp 808, and is still 9mm deeper in rim profile. Thanks to Easton Variable Nipple Bed (VNBTM) Technology. This process of internally tapering the rim bed eliminates excess carbon between spoke holes and allows for a sharper inner edge. There are two ways to make a wheel fast in the wind. One is to design the leading (forward) edge to help smooth the path of the air around the tire. Zipp bulged rim profile attempts to do this. The other way to design a fast wheel is to focus on sharpening the rim profile on the trailing edge to manage the air as it exits the rear edge of the wheel. You can not have it both ways. At Easton we feel you can design a faster wheel with a sharper, narrower profile like the EC90. And Easton wind tunnel data confirms this. Dimples work on blunt objects like golf balls, but they're irrelevant on bicycle wheels.

Now what about the Dimples; on a golf ball, the dimples reduce drag because they create turbulent flow. They diminish what is called pressure drag, caused by a relative void behind the ball. However on sharper, wing shaped objects like deep section rim; or F1 cars dimples do not work because the air is already flowing over a narrow, optimized shape that by design reduces pressure drag. Features:

• Wheel size 700C
• Hubs F-R4TT and R-R4SL
• Rims Easton Front 56mm and Rear 90mm carbon tubular
• Spokes Sapim bladed black, straight pull; 12F(90mm)/16F(56mm) radial and 16R radial NDS/2-cross DS
• Nipples Alloy black internal
• Bearings Custom Grade 3 ceramic bearings
• Weight 1440g (90mm Front/Rear)
• SwissStop pads included
• Shimano and Campagnolo specific sets