Zipp 303 Firecrest clincher tubeless disc Centerlock 650B wheel

303 Firecrest 650b Carbon Tubeless Disc-brake

The definition of “road cycling” now includes gravel and dirt as well as pavement. At the same time, bikes are evolving to meet the fit requirements of smaller riders. Meeting these two distinct needs was the driving force behind the Zipp 303 Firecrest 650b Tubeless Disc-brake wheelset. The smaller rim size provides room within frames and forks for larger tires, 28mm or wider, that deliver increased comfort, compliance, and cornering performance. With more tire between the rim and the ground, the overall wheel diameter including the tire is similar to a standard 700c wheel and road tire combination. Back on the pavement, the 650b is a better fitting wheel for smaller athletes riding compatible frames. For too long, many smaller cyclists have trained and raced on standard 700c wheels, losing out on the advantages of a proper fitting wheel such as improved handling and the elimination of front wheel-toe overlap. At the center of the 303 650b Firecrest Tubeless is a versatile and durable hubset, the German-engineered ZR1 DB.

• Zipp graphics and cosmetic identity that scream speed
• Versatile 45mm rim profile for increased speed and better cornering, control and comfort
• Tubeless design provides secure performance when ridden at lower tire pressures
• ZR1 DB hubset is engineered in Germany with better seal design for improved durability and quicker response with 66 points of engagement
• Built with Sapim CX Sprint J-bend spokes
• Center locking rotor interface. Lockring is included
• Ships with 12mm front and rear end caps
• XDR or SRAM/Shimano driver bodies
• Campagnolo driver body sold separately

Technologies

ABLC (Aerodynamic Boundary Layer Control)
Advanced Boundary Layer Control (ABLC) refers to the patented and instantly recognizable dimpled pattern found on all of our carbon rims. ABLC smoothes airflow across the rim's surface and is tailored to every model from the 202 to the Super-9 Disc. The third-generation of ABLC has up to four times more dimples than before.

AeroBalance
Zipp’s sole mission is to help you go faster. That's why our wheels are race-ready before they're camera-ready. For years, Zipp has used a combination of testing methods – wind tunnel, CFD computer simulations, pro athlete evaluations, on-road testing, and the RollingRoad ride simulator – to refine aero performance to new levels of excellence. Over the decades of innovation, our engineers have learned to look beyond just focusing on simply reducing aero drag. Instead, the goal now is to reduce aero drag while also minimizing the effects of crosswinds on handling. This optimizing of aero efficiency and crosswind stability became known internally at Zipp as AeroBalance. The approach began with Firecrest technology and has been advanced with the introduction of the NSW lineup, especially with the Sawtooth technology found in the 454 and 858 NSW. Sawtooth accomplishes this with a series of patented fin-shaped Hyperfoil nodes along the inner diameter of the rim that work together with our new HexFin ABLC dimples for improved airflow.

TSE Technology
Zipp’s TSE Technology (Total System Efficiency) was developed by our engineers in the Nest Advanced Development Lab in Indy. This approach to carbon-wheel manufacturing means the 303 Firecrest’s precise rim layup results in greater all-around efficiency for greater speed through reduced: Wind resistance, rolling resistance, gravity (weight + durability), vibration losses.

Specifications

• Size (wheels): 650B
• Rim construction: Carbon w/Hooks
• Tire compatibility: Clincher or Tubeless tires
• Brake compatibility: Disc (Center Lock)
• Driver body type: SRAM XDR, SRAM/Shimano Road
• Rim inside width: 21mm
• Rim finish: UD fiber, adhesive decals
• Rim profile: Symmetrical