Shimano Ultegra R8000 Crankset 165mm 50-34T Compact Road Bike Chainset

Shimano Ultegra Hollowtech II Crankset (IFCR9100AX04)
Engineered for precision and performance, this double-chainring system (50/34T) combines featherlight construction at 674g with military-grade durability through its forged chromoly crank arms. Designed exclusively for road cyclists prioritizing speed efficiency and long-term reliability, the Hollowtech II spindle interface delivers 20% greater torsional rigidity than standard square taper designs—critical for maintaining cadence stability during sprints or climbs.

Key Innovations
– Asymmetric Chainring Geometry: Reduces chain deflection by 15% compared to symmetrical models, ensuring smoother shifts under heavy load
– Wider Gear Pitch Clearance: Expands chain-to-teeth spacing by 2mm compared to prior generations, preventing derailment in muddy or wet conditions
– 130/135mm Hub Compatibility: Works seamlessly with both traditional road frames (130 BCD) and modern disc-equipped road bikes (135/142mm spacing)

Performance Metrics
– 165mm crank arm length optimized for cyclists aged 170-185cm
– -15°/+15° chainring offset improves power transfer efficiency by 8% on steep gradients
– Black anodized finish withstands urban brake dust exposure without requiring frequent cleaning

Road-Specific Advantages
Ideal for competitive road cyclists tackling criterium circuits or gran fondosos requiring consistent power delivery through variable terrain. The proprietary hollow forging process reduces rotational inertia by 12%, enabling quicker acceleration from standing starts—a key benefit for criterium racers and breakaway specialists.

Technical Comparison
| Feature | Ultegra Hollowtech II | Competitor Model X |
|———————–|———————–|——————–|
| Weight | 674g | 712g |
| Spindle Interface | Hollowtech II | Square Taper |
| Chainring Asymmetry | Yes | No |
| Q-Factor | 144mm | 148mm |

Built without integrated bottom bracket (sold separately), this system pairs perfectly with Shimano Ultegra groupsets (11-speed) for riders seeking a balanced upgrade between entry-level alloy cranks and premium carbon fiber options.