Look 765 Optimum Ultegra Di2

Look

765 OptimumUltegra Di2

FrameLOOK (model unspecified)LOOK (model unspecified)
GroupsetSHIMANO ULTEGRA Di2 R81…SHIMANO ULTEGRA R8100, 11…
WheelsLOOK R 38 D Carbon Tube…HUTCHINSON Fusion 5 Tubeles…
Tire clearance34 mm

The Look 765 Optimum is a dedicated endurance road platform redesigned from the ground up for the 2023 model year. Moving away from aggressive race postures, Look explicitly shaped this generation to prioritize long-distance comfort and straight-line stability over quick agility. The chassis is built around a threaded T47 bottom bracket and features Look's 3D Wave rear triangle, which uses flattened and scalloped tube profiles to increase compliance on rough pavement.

Practicality is a clear focus for the platform. The frame clears 700x34mm tires and includes recessed mounts for mudguards, making it a capable companion for varied weather and deteriorating backroads. A semi-integrated routing system keeps cables hidden while allowing riders to remove the handlebar and stem without disconnecting hydraulic hoses. It is a bike built for cyclists who want a reliable, smooth-riding machine for high-mileage days rather than explosive sprint finishes.

Look 765 Optimum
Build
Size
01 / Buy

Where to get it.

2 retailers · size S.

Size
2 retailers · Size S
02 / Specifications

Spec sheet.

Every component shipped with this build.

01Frameset
2 components
FrameLOOK (model unspecified)
ForkLOOK (model unspecified)
02Drivetrain & brakes
11 components
CranksetSHIMANO ULTEGRA (exact model/chainring size not specified)
Bottom bracketT47 V24 85.5 / Token
Front rotorSHIMANO RT-MT800, 160mm
Rear rotorSHIMANO RT-MT800, 140mm
03Wheels & tires
4 components
Front wheelLOOK R 38 D Carbon Tubeless
Rear wheelLOOK R 38 D Carbon Tubeless
Front tireHUTCHINSON Fusion 5 Tubeless Ready, 700x30
Rear tireHUTCHINSON Fusion 5 Tubeless Ready, 700x30
04Cockpit & contact
4 components
StemLOOK LS3 Alloy (XS 80 / S 90 / M 100 / L 110 / XL 120)
HandlebarsLOOK LS3 Alloy (XS 38 – S 40 / M – L 42 / XL 44)
SaddleLOOK by SAN MARCO Short Fit Dynamic Open Fit
SeatpostLOOK LS1 Carbon Super Light 27.2mm, 350mm
03 / Geometry

Geometry & fit.

5 sizes published.

The 765 Optimum utilizes a progressive geometry concept that pairs a relaxed front end with a relatively steep seat tube. Across all five sizes, the head tube angle sits at a slack 70.8 degrees, while the seat tube angle remains fixed at 74.0 degrees. This combination places the rider in an upright, efficient pedaling position over the bottom bracket while pushing the front wheel further out. The result is a highly stable steering feel that resists being deflected by potholes or crosswinds, though it requires more deliberate input to navigate tight corners.

Stack and reach figures reflect a classic endurance posture, ranging from 534mm and 358mm on the XS to 630mm and 399mm on the XL. This setup keeps the rider's weight comfortably distributed to reduce lower back and neck fatigue on extended rides. The 415mm chainstays provide enough length to accommodate 34mm tires and mudguards while contributing to the bike's steady, predictable tracking on fast descents.

Reach × Stack · size Smm

Where the handlebar sits relative to the bottom bracket — the single most important fit pair.

645599553506460STACK ↑335355375395415REACH →ENDURANCERACE / AEROSize S368 · 558
01Fit geometry6 values
Stack558 mm
Reach368 mm
Top tube528.7 mm
Headtube length142 mm
Standover height766 mm
Seat tube length490 mm
02Component geometry2 values
Handlebar width400 mm
Stem length90 mm
03Handling geometry7 values
Headtube angle70.8°
Seat tube angle74°
BB drop76 mm
Trail67 mm
Offset50 mm
Front center594 mm
Chainstay length415 mm

Which size should I buy?

Slide your height to see the recommended size. GearWise's fit algorithm works from the published stack, reach, and ETT — the brand's own recommendation may differ.

Your height
5'8"173 cm
5'0"5'5"5'10"6'3"6'7"
Recommended sizeSBased on stack, reach & ETT for your height · score 40/100.

Calculated from GearWise's own stack / reach / ETT algorithm — the brand's size chart may recommend a different size, and a proper bike fit beats any calculator.

04 / Other builds

The lineup.

3 builds, ranging $4,000 – $7,500.

The 765 Optimum lineup spans three builds, all utilizing Shimano 12-speed drivetrains and the same core carbon frameset. The entry point is the Shimano 105 mechanical build, which pairs a standard 105 R7100 groupset with an RS520 crankset and basic Shimano RS171 alloy wheels. This model uses an alloy Look seatpost and Hutchinson Challenger tube-type tires, keeping the price accessible while delivering reliable shifting.

Stepping up to the mid-tier 105 Di2 model introduces electronic shifting and upgrades the seatpost to Look's LS1 Carbon Super Light model, which helps maximize the frame's rear-end compliance. It retains the heavy Shimano RS171 alloy wheels but moves to tubeless-ready Hutchinson Fusion 5 tires.

The flagship Ultegra Di2 build represents a significant jump in both performance and price. It features a full Ultegra Di2 groupset and swaps the alloy hoops for Look's R 38 D carbon tubeless wheels. This wheel upgrade materially reduces rotational weight, addressing the sluggish acceleration noted on heavier builds, while the carbon rims and 30mm tubeless tires further refine the bike's premium ride quality. All builds feature compact 11-34T cassettes to support seated climbing.

01
Ultegra Di2 build
· Currently viewingUltegra Di2
$7,500On this page
02
105 Di2 build
105 Di2
$5,400
03
Shimano 105 build
Shimano 105
$4,000
05 / Reviews

From the press.

2 reviews from the cycling press.

Reviewers consistently characterize the Look 765 Optimum as a highly stable, smooth-riding machine that excels at maintaining momentum over long distances. The frame's vibration damping is a standout trait, with testers noting it easily "glides over rough surfaces" (Cyclonline) and effectively mutes road chatter. Rather than feeling like a demanding race bike, it behaves more like a "GT car" (YouTube) that allows riders to cruise comfortably for hours.

This emphasis on composure comes with a deliberate tradeoff in handling dynamics. The steering is predictable but not particularly sharp. Testers observe that the bike "definitely understeers" (YouTube) and requires a slower entry speed into tight corners. However, this same geometry makes it a "stable locomotive on rails" (Cyclonline) on fast descents and in heavy crosswinds, where it remains steadfast and secure.

When the road points uphill, the 765 Optimum is efficient but not explosive. Reviewers agree that the frame is stiff enough around the bottom bracket to transfer power cleanly during seated efforts, but it lacks the snappy acceleration needed for steep, out-of-the-saddle attacks. Ultimately, testers view these traits as a smart compromise, resulting in a highly capable platform for riders who value steady pacing and fatigue reduction over aggressive climbing speed.

06 / Compared to

Compared to.

Most-viewed comparisons.