A carbon road bike made for the miles you want to keep riding. The LOOK 765 Optimum Shimano 105 / RS171 balances efficient road performance with a more accommodating position, predictable handling and the versatility of up to 34 mm tire clearance.
The Proteam Black Glossy finish gives this everyday endurance bike the unmistakable LOOK identity. Underneath: a purpose-built carbon chassis, mechanical Shimano 105 12-speed shifting, Shimano RS171 wheels and a LOOK LS1 carbon seatpost.
The 765 Optimum is made for riders who want a responsive carbon road bike but do not want every ride to feel like a race-day position. LOOK pairs a shorter reach and taller head tube with a carbon layup engineered to balance stiffness and compliance.
The endurance geometry offers a less extreme posture for century rides, long climbs, training blocks and busy roads.
Up to 34 mm tire clearance creates room for wider road tires, improving setup flexibility for rougher pavement.
A carbon frameset, 12-speed 105 gearing and hydraulic discs keep this firmly in the performance-road category.
Rather than treating comfort as an accessory, LOOK developed the 765 Optimum around an endurance-specific blend of carbon fibers, frame shaping and geometry. The aim is a planted, precise road bike that remains comfortable when the surface deteriorates or the ride stretches past the usual distance.
The 765 Optimum platform is also described by LOOK with its 3D Wave rear-stay comfort concept. This is an endurance-specific design intended to help absorb road vibration; it is not a suspension system.
Shimano 105 mechanical 2x12 gives riders crisp indexed shifting and familiar serviceability without adding the cost or charging routine of electronic shifting. With a listed 11–34T cassette and dealer-reported compact 50/34 chainrings, the setup is well suited to varied terrain, training and long climbs.
The Shimano RS171 wheels give this build a dependable alloy starting point. For riders planning future upgrades, changing wheels and tires is a straightforward way to tune the ride without replacing the underlying endurance chassis.
Mechanical shifting and the close control of a modern 12-speed double road drivetrain.
Everyday road wheelset, leaving upgrade flexibility for later carbon-wheel ambitions.
A useful premium touch on a bike designed around maintaining comfort over distance.
There is no universal best road bike. The useful comparison is what each platform asks of the rider and which details matter over a full season. For riders comparing the mechanical 765 Optimum against electronic endurance builds or the aerodynamic Blade RS family, the differences are straightforward.
| Decision point | 765 Optimum 105 (this bike) | 765 Optimum 105 Di2 | 795 Blade RS |
|---|---|---|---|
| Primary purpose | Everyday speed, long-distance comfort, endurance events | The same endurance-road platform with electronic shifting | Purpose-built aerodynamic road racing |
| Riding position | Shorter reach and taller front end, tuned for longer time in the saddle | Same underlying endurance geometry | Lower, more aggressive race-oriented fit |
| Shifting | Shimano 105 mechanical 2x12 | Shimano 105 Di2 electronic 2x12 | Race-build-dependent: SRAM / Shimano / Campagnolo electronic groups |
| Standard wheels | Shimano RS171 alloy | Shimano RS171 alloy in the referenced LOOK trim | Carbon race wheels on premium builds |
| Tire accommodation | Up to 34 mm | Up to 34 mm on the 765 platform | Road-race tire clearance depends on exact Blade RS generation |
| Best choice if | You want serviceable, reliable mechanical shifting and endurance comfort | You value push-button electronic shifting over the simplest configuration | Aerodynamics and high-speed racing outweigh endurance comfort |
All-day training, fondos, centuries and back-to-back road rides, with a less aggressive position than a race-focused Blade RS.
A substantial endurance-road frame with modern Shimano 105, hydraulic disc braking and upgrade potential.
From smooth roads to imperfect secondary roads, the 34 mm maximum tire clearance makes practical tire choices possible.
The table below follows LOOK's current 765 Optimum 105 / RS171 product listing. Where LOOK has not specified an exact OEM part, that omission is flagged instead of filling it with a guessed component. A separate dealer reference supplies the compact chainring and hydraulic-disc information.
| Model | LOOK 765 Optimum 105 / Shimano RS-171 |
| Category | Carbon endurance road bike |
| Finish | Proteam Black Glossy |
| Frame | LOOK 765 Optimum endurance carbon frame, multiple-fiber layup |
| Fork | LOOK 765 Optimum carbon fork |
| Drivetrain | Shimano 105 mechanical, 2x12-speed |
| Shifters | Shimano 105 mechanical 12-speed |
| Front / rear derailleurs | Shimano 105 12-speed |
| Crankset | Shimano 105, 50/34T (dealer-listed; confirm final OE specification) |
| Cassette | Shimano CS-R7101, 11-34T |
| Chain | 12-speed chain (exact OEM model not confirmed on current LOOK listing) |
| Brakes | Shimano 105 hydraulic disc (dealer-listed) |
| Bottom bracket | Token T47 |
| Wheels | Shimano WH-RS171 |
| Tires | Manufacturer product page does not identify exact tire model; maximum frame clearance 34 mm |
| Handlebar | LOOK LS3 Alloy |
| Stem | LOOK LS3 Alloy |
| Seatpost | LOOK LS1 Carbon Superlight, 27.2 mm x 350 mm |
| Saddle | LOOK by San Marco Short Fit Dynamic Open Fit |
| Weight | 7.9 kg claimed for size M on LOOK product page; not a weight for every size |
| Sizes | XS, S, M, L, XL |
| U.S. listed price | $3,600 |
Manufacturer specifications and availability may change. Verify tire model, brake rotor sizes and any equipment substitutions with Brimstone Bicycles before purchase.
The endurance fit begins with stack and reach, then the full geometry refines your riding position. All linear dimensions below are in millimeters unless stated otherwise. Geometry comes from LOOK's official XS–XL chart.
| Measurement | XS | S | M | L | XL |
|---|---|---|---|---|---|
| Stack (mm) | 534 | 558 | 582 | 606 | 630 |
| Reach (mm) | 358 | 368 | 379 | 389 | 399 |
| Head tube angle (degrees) | 70.8 | 70.8 | 70.8 | 70.8 | 70.8 |
| Seat tube angle (degrees) | 74 | 74 | 74 | 74 | 74 |
| Seat tube (mm) | 470 | 490 | 510 | 535 | 560 |
| Effective top tube (mm) | 511.8 | 528.7 | 545.5 | 562.4 | 579.3 |
| Front center (mm) | 576 | 594 | 613 | 631 | 650 |
| Trail (mm) | 67 | 67 | 67 | 67 | 67 |
| Fork offset (mm) | 50 | 50 | 50 | 50 | 50 |
| Chainstays (mm) | 415 | 415 | 415 | 415 | 415 |
| Head tube length (mm) | 117 | 142 | 170 | 195.3 | 223.4 |
| Fork length (mm) | 385.5 | 385.5 | 385.5 | 385.5 | 385.5 |
| BB drop / HAV (mm) | 76 | 76 | 73.5 | 73.5 | 71 |
| Standover (mm) | 742 | 766 | 790 | 814 | 838 |
A geometry table supports sizing, but does not replace an individualized bike fit. Contact Brimstone Bicycles to discuss fit, stem length and tire setup.
It is a performance-focused endurance road bike. Its taller front end and shorter reach are designed for spending longer hours comfortably in a road riding position while retaining responsive handling.
This specific LOOK 765 Optimum Shimano RS171 uses mechanical Shimano 105 12-speed shifting, not 105 Di2. LOOK sells separate electronic-shifting versions.
LOOK specifies frame clearance up to 34 mm. Actual installed tire clearance depends on the rim and tire combination; confirm clearance after installation.
Both are endurance-oriented 765 Optimum bikes. The primary distinction is the shifting system: mechanical Shimano 105 versus electronic Shimano 105 Di2. Confirm the exact wheels and included components on any individual build.
The 765 Optimum prioritizes all-day comfort and a more accommodating position. The 795 Blade RS is the sharper aerodynamic race-bike option for riders prioritizing aggressive road-race performance.
Yes. LOOK lists the LS1 Carbon Superlight 27.2 mm seatpost on this Shimano 105 / RS171 configuration.
XS, S, M, L and XL. The full manufacturer geometry table is included above. For fit help, contact Brimstone Bicycles before ordering.
No. LOOK publishes 7.9 kg for size M. Complete-bike weight varies with frame size and can vary with final equipment.
For a rider who wants a carbon endurance road bike with reliable mechanical shifting and room to personalize fit and tires, the 765 Optimum Shimano 105 / RS171 is a considered choice. It brings the LOOK carbon-road experience into a package meant to be ridden often, not saved for perfect conditions.
Questions about frame sizing, component availability or the best setup for your local roads? Contact Brimstone Bicycles. We can help compare the 765 Optimum against LOOK's electronic endurance and Blade RS race models before you decide.
Ready to ship in 2 days.
Our regular policy applies, please check our return policy for more details.
Your cart is currently empty.
Start Shopping
