Lots of news on the wheel front here in Germany at the Eurobike trade show. Naturally there are plenty of carbon rims stamped from the same mold, but a few jump out with original engineering and design.
Zipp’s position at the top of the leaderboard in the study of wheel aerodynamics is hard to dispute. Armed with some impressive drag data and computational fluid dynamics illustrations, head of engineering Josh Poertner proudly introduced Zipp’s new 808 rims.
The new rim features the company’s Firecrest profile, a rim shape that debuted with the 404 clincher earlier this season. It’s got wide, parallel walls and a fat, blunt inner rim wall (spoke bed). Zipp’s earlier designs placed a toroidal bulge behind the tire to reduce turbulence at the wheel’s leading edge, but Firecrest shifts the widest point of the rim inward towards the hub and tapers only slightly towards the tire. The blunt shape helps keep airflow attached to the wheel and laminar as it comes off the sidewalls and exits the wheel’s path. The new 808 also sports a wide tire bed that Zipp carefully shaped to match the profile of 23c tubular tires for better glue adhesion. And, the edges of the tire bed are now reinforced and profiled in the same way as the 303 rims, for better impact and pinch flat resistance.
In addition to the tubular 808, there’s a carbon clincher version. The rim shape and aerodynamics are exactly the same as the tubulars. Despite their upgraded aerodynamics, weights for Firecrest-based wheels remain quite light: 1278g for the 404 Tubular, 1557g for the 404 Carbon Clincher, 1519g for the 808 Tubular, and 1759g for the 808 Carbon Clincher. Suggested retail prices are $2300 for the 404 Tubular, $2700 for the 404 Carbon Clincher, $2500 for the 808 Tubular, and $2950 for the 808 Carbon Clincher. Clincher wheels with aluminum braking surfaces are still available for both the 404 (1658g, $2,300) and 808 (1912g, $2,500).
With a factory literally just a few kilometers from Messe Friedrichshafen where Eurobike convenes annually, local builder Lightweight’s display in the show hall is popular. The company showed off a new disc wheel with a claimed weight of just 780 grams. It’s built with tensioned carbon strands similar to their original, internally spoked disc.
Also new from the Germany company is a radical eight-spoke front wheel. Lightweight built it as an aerodynamic complement to the disc. Claimed weight is 650 grams with significant improvements to airflow and no reduction in stiffness.
We’ll have more details from Lightweight in the weeks to come.
Not to be outdone by Zipp’s 303, Hed introduces the Stinger 5. It’s built with a rim shape similar to the 46mm deep Stinger 4, but the tire bed and aerodynamics are engineered specifically for 25mm and larger tires. The Stinger 5 is Hed’s version of a cyclocross and classics-style wheelset. The rims are built for impact resistance and strength.
Hed also widens the aluminum tubular tire bed of the Ardennes series of wheels and brings carbon fiber front hubs to most of the entire wheel line. Finally, the rear wheels move to 2-cross lacing for added stiffness.
Aerodynamics and composites wizard Paul Lew showed off some of his designs in the Reynolds booth. Lew takes an approach opposite of that employed by Hed and Zipp, relying on extremely sharp edges and NACA aero profiles in his rims and spokes.
New in the line this year is the addition of a small lip or “trip” at the spoke bed on Reynolds’s entire road rim line. This “Swirl Lip Generator” debuted on the ultralight, sub-900 gram RZR wheelset last year and is meant to deliberately trick airflow into moving more smoothly across the rim. Also new is a different carbon material and high temperature resin in the brake track. Combined with new pads, Lew claims a 100-degree Fahrenheit reduction in brake pad and track surface temperature.
Finally, Lew’s moving forward with an updated version of the original RZR wheel. It turned heads last year as the lightest production wheelset ever built, but didn’t meet the needs of certain riders. So Lew and Reynolds added about 100 grams to the wheelset to improve stiffness and to pass the UCI’s crash-impact test. The new version of the RZR is still extremely light at just around 1000 grams for the pair, but should be quite a bit stiffer than the original.
Check the photo gallery for more details on these and additional wheel developments.