Narrow is faster - Easton’s proprietary narrow-flange R4TT front hub reduces frontal spoke area by 50% for improved aerodynamics. Combined with a new wind tunnel-tuned 90mm rim, and the new EC90TT displays lower drag than the Zipp 808 at 0, 5, 10, 15 and 20 degree yaw angles. It even rivals the much deeper (and heavier) Zipp 1080 at 5 and 15 degrees.
Faster and lighter - At 1424 a set, the EC90 TT is a full 30 grams lighter than the Zipp 808, and still 9mm deeper in rim profile, thanks to Easton’s Variable Nipple Bed (VNB™) Technology. This process of internally tapering the rim bed eliminates excess carbon between spoke holes and allows for a sharper inner edge. Less weight, improved aerodynamics with no loss in strength.
Aerodynamics 101: leading edge vs. Trailing 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’s 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’t have it both ways. At Easton we feel you can design a faster wheel with a sharper, narrower profile like the EC90. And our wind tunnel data confirms this.
Dimples are for golf - Dimples work on blunt objects like golf balls, but they’re irrelevant on bicycle wheels. On a golf ball, they reduce drag because they create turbulent flow. They diminish what's called pressure drag, caused by a relative "void" behind the ball. However on sharper, wing-shaped objects like deep section wheels (or F1 cars) dimples don’t work because the air is already flowing over a narrow, optimized shape that by design reduces pressure drag.
Easton EC90 TT Road Front Wheel Features:
Wheel size: 700C
Weight: 1424 grams
Hubs: F-R4TT R-R4SL
Rims: Easton 90mm carbon tubular
Spokes: Sapim™ bladed black, straight pull
Nipples: Alloy black (internal)
Bearings: Custom Grade 3 ceramic bearings
*PLEASE NOTE – Shimano rear wheel is only compatible with 10 speed cassettes*
Buy Easton EC90 TT Road Front Wheel from Chain Reaction Cycles, the worlds largest online bicycle store.
Rated 5 out of 5 by Anonymous Great TT wheel
Used this wheel for the first time in a time trial this weekend and the feeling was great. This really gave my time trial (Cube Aerium hpc) bike a lift. Highly recomend it. :-)
15 April 2012