Carbon Wheel Aerodynamics

Wind Tunnel Investigation December 21st 2016

Objective

To compare and analyze (1) hie cycling wheel drag in relationship to other manufactures (2) Provide drag comparison to two bike manufactures (3) Provide drag information of two skin suit manufactures (4) Provide drag information of two TT/Triathlon helmets. Note: 2,3 & 4 are provided to give an idea that there are variations in shapes and material.

Wheel configuration, bike configuration, skin suit configuration, helmet configuration

Wheel Configuration: Two major wheel manufactures were used to compare the hie cycling LL60 clincher wheel. These manufactures were priced the same or significantly higher to the hie cycling LL60. Same tire and air pressure was used across all wheels. Multiple repeats and data points were taken throughout testing.

Bike Configuration: The Bottechia was compared to another major brand with similar configuration on the front end. The same wheels and tires were used to compare the two.  Multiple repeats and data points were taken throughout testing.

Skin Suit Configuration: Canari Skin Suit was tested against a major competitor using the same body, bike, and wheels. Body Position was checked multiple times making sure rider was maintaining positon.  Multiple repeats and data points were taken throughout testing.

Helmet Configuration: Tests analysis provided by Sh+ for information (not tested by Faster). To be provided shortly.

Wheel performance gains over competitors

The hie LL60mm wheel performance in the tunnel provided data showing that it is better than its competitors.  Competitor wheel A is priced very closely to the hie Cycling wheel. Whereas, competitor B is priced much higher. The power difference between the hie LL60 and comp A is 5 watts at 30mph on between 0 and 5 degrees. In addition, the hie LL60 was only 2 watts slower than the much higher priced competitor B. This is a significant result showing how well designed the hie LL60mm is.

Looking across the complete sweep from 0 degrees to 10 degrees the difference between hie LL60 and significantly higher priced competitor B is 0 watts. The hie LL60mm is a very competitive wheel.

PERFORMANCE BASED ON ROTATION (IN DEGREES)

0 degrees

hie Cycling – 29.175 | Competitor A – 30.28 | Competitor B – 28.07

5 degrees

hie Cycling – 27.33 | Competitor A – 28.44 | Competitor B – 26.96

10 degrees

hie Cycling – 24.005 | Competitor A – 22.16 | Competitor B – 22.53

Results comparing Bottecchia (bike) and another brand

The Bottecchia performed quite well having a significant time savings over Competitor A. On Average the Bottecchia is 16watts faster than the Competitor A bike. The Bottecchia did not increase or decrease throughout the sweep. Competitor A did change quite a bit. This is likely do to tube shapes and handle bar differences.

Results comparing Canari skin suit to Competitor A

The Canari Skin Suit was considerably quicker the Competitor A. On average the savings was 12 watts between the two skin suits. Whether looking at 0 to 10 degrees or 0 to 25 degrees the savings was still a significant 12 watts. Furthermore, taking into account an athlete’s equipment preferences, fit and body positions the results may change slightly. That change would likely be small considering the performance gap between Canari and Competitor A.

TUNNEL INFORMATION

Tunnel: Ride-Faster Wind Tunnel, Cycling specific testing facility.
Location: Phoenix, Arizona USA
Date: December 21st 2016

TUNNEL CONFIGURATION

Wind speed: 30mph
Wheel speed: 30mph
SATP: Standard conditions for temperature and pressure – in grams
Rider: Mathew Shackley (For bike & skin suit manufacture runs)
Table Angles: 5 degree increments: 0 to 25
Drag Force: Taken in wheel axis and bike axis (not wind axis)
But we still recorded data in Wind axis