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2009 Updates for HED and Zipp Wheels.
By Tom Demerly.
Read this first about our reviews

2009 Updates for HED and Zipp Wheels. 2009 Updates for HED and Zipp Wheels.


HED's ultra-high speed combination: The H3C Deep front and Jet Disk rear. The new Jet Disk uses a lenticular shape and rim bulge for optimized aerodynamics. The profile of the most recent versions of the HED's disks have been optimized for use with new aero bike rear ends such as Cervelo's P3. It will provide optimal clearance on some, but not all, newer aero frames. This rear disk uses the new, wider rim width: 22 mm wide at the center of the brake track. This wider profile lowers tire rolling resistance and improves low speed aerodynamics. A few bikes have narrow enough chainstays that a new HED disk won't fit, among them Cervelo's vaunted P4 for '09.

2009 Updates for HED and Zipp Wheels.

HED's H3C Deep was a custom one-off wheel made for the pros, and is now available to us. The H3C Deep uses a carbon fiber fairing affixed to a standard H3C molded in Spain for HED. This is an excellent rear wheel especially on windy courses. The H3C and new H3C Deep are only available in the narrower, 19 mm rim width.

2009 Updates for HED and Zipp Wheels.

A close look at the fairing between the HED 3C Deep rim and the strut with the fairing affixed by HED over the standard depth HED 3. So basically, this is an enhanced HED 3 from HED's speed shop. Early prototypes of this wheel were seen on time trial bikes used in the Tour de France by Viatcheslav Ekimov, George Hincapie and Lance Armstrong. This wheel is an excellent rear at normal race speeds (20-24 M.P.H. average speeds) and a good front wheel choice for extremely fast time trialists that can maintain average speeds in excess of 25 M.P.H. For us mortals between 20 and 23 M.P.H. average speed during our bike split the standard depth HED 3C is a better choice in the front. A standard HED 3C in the front with a HED 3C Deep in the rear would also be an excellent combination for the rank n' file age grouper.

2009 Updates for HED and Zipp Wheels.

The complex shape of the new HED Jet disk is optimized for low speed aerodynamics (20-35 M.P.H.) with the new wider rim, rim bulge and lenticular profile. This is one of the newer disks for use with many narrow chainstay fit bikes such as the Cervelo P3. For very wide chainstays such as the P4 a flat disk will have adequate clearance.

2009 Updates for HED and Zipp Wheels.

Can you see the difference in width between old and new? The new, wider 22 mm rim track is on the left, the traditional 19 mm wide rim track on the right. This new, wider configuration enhances speed, aerodyanmics and ride comfort while lowering rolling resistance. All new HED wheels (except H3C) have the new, wider configuration.

2009 Updates for HED and Zipp Wheels.

The clincher versions with the new, wider profile on the left and the previous version on the right. Particularly for clincher tire riders the new, wider HED rims offer significant benefits in speed, ride quality and flat resistance.

2009 Updates for HED and Zipp Wheels.

Zipp has completely redesigned their hubs with a small, locking dust cap for setting bearing preload and for better protection of the bearings themselves. The new hubs are beautifully and precisely machined. This is a big improvement over the previous carbon fiber dust caps.


2009 Updates for HED and Zipp Wheels.

The dimpled surface of the Zipp rim has been improved for a better cosmetic presentation. Older dimpled Zipp wheels often had a series of small lines extending outward from the dimples. While this was cosmetic, some consumers mistook these for small cracks. Zipp's new molding and lay up processes have removed this cosmetic concern for a better overall look. Even the inflation holes have less carbon flashing around them.

2009 Updates for HED and Zipp Wheels.

Zipp has also moved to a wider rim profile for improved aerodynamics and lower rolling resistance. This new, wider profile enables lower tire pressures and better ride quality which actually result in higher speeds. The ability of a tire to deform around irregularities in road surfaces is what lowers the rolling resistance.

2009 Updates for HED and Zipp Wheels.

A close look at the excellent molding of the dimples on the new Zipp 404's. Zipp has also changed the brake surface of the rim to be perfectly parallel or flat sided. This enables the brake pad to contact the rim more precisely for better stopping power, espeically in wet conditions. Notice the complex, constantly changing radii of the rim surface comprised of seven different changes in radius. This evolution is the result of constant re-evaluation of Zipp's rim designs. The newest version of the Zipp 404 is actually in its sixth generation of design updates making it the most sophisticated version to date.
2009 Updates for HED and Zipp Wheels.

With the new hub, improved rim and optimized width the Zipp deep section wheels in all models have been significantly updated. The new hub with alloy dust cap looks nicer along with better cosmetics on the rim.

 

2009 Updates for HED and Zipp Wheels.
A close look at Zipp's new, beautifully machined hub and bolt-on dust cap. Compared to the previous carbon fiber dust cap retained by an "O" ring this is a much nicer design: More durable, keeps the bearings cleaner and looks nicer.

2009 Updates for HED and Zipp Wheels.
Zipp uses a solid pawl freehub with wider deployment springs for better freehub ratcheting. The springs are the thin brass colored flaps under the silver pawls that press them upward. These wider pawls provide good power transfer.

2009 Updates for HED and Zipp Wheels.

Ease of maintenance on the Zipp hubs has always been excellent. With the new hubs however, it is improved but the need for maintenance, because of better hub seals, is almost eliminated. Notice the three silver coloed ratcheting "pawls" on the red free hub body with the thin leaf springs under them. This is what controls your rear wheel's ratcheting action: It engages when you pedal and coasts (or "freewheels") when you stop pedalling allowing your bike to coast.

2009 Updates for HED and Zipp Wheels.

The simple, elegant dissection of Zipp's excellent new hub. The blue precision bearing is seated precisely in the hub shell resulting in bearing performance that is better than some aftermarket ceramic bearings. Preload on the bearings is set by the locking dust cap that now tightens using an allen wrench, maintaining constant adjustment. Previous versions relied heavily on the force of the quick release skewer to maintain good adjustment. This new seal system is also more weather proof.

 

© Tom Demerly, Bikesport Inc.


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