What's Cool In Road Cycling

LOOK 765 RS Gravel Project Bike Build & Review

I’ve been working on this latest project bike for some time, but it’s definitely been worth the wait.  Built around Look’s entry to the gravel riding scene –  their 765 RS carbon frameset, I added Corima 30.5 carbon allroad wheels, SRAM Force AXS electronic gruppo, ZIPP Service Course SL 70 XPLR handlebar, Zipp Service Course SLR carbon seatpost, Cadex saddle, Arundel Cages and saddle bag, Lizard Skins bar tape.

It’s been many years since we reviewed a Look bike – but I can tell you I’ve been a fan of the brand from way back.  France have deep roots in cycling (Even if Italian brands seem to have more cache).  LOOK have built a leading global cycling brand based on innovation (I can think of no better example than clipless pedals), design (the bikes have almost always had a certain distinction to them that says “European”) as well as keeping much of their production in house to better control quality (in times when even the most revered Italian brands sent it all off shore).

It’s easy to see the frame is designed with the best practice guidelines – based on what frame builders have learned in the last 20 years how to design and work with carbon fiber.  The massive downtube flows into an equally large bottom bracket (more pics below).  There’s also enough room in there for an e-bike motor, and Look uses the Fazua Evation motor design for the e-bike version of the RS gravel.

That large downtube is ideally designed to anchor the headtube-downtube-BB-chainstay quadrumvirate of drivetrain stability and control.  You can also see the other part of this equation – the tapered top tube, slightly curved & sloping, that transforms to the purpose-shaped chainstays – which is designed to allow enough flex to add some rider comfort to the mix.

Styling around the front end sets the tone for the rest of the frame – smooth, subtle and functional.  The cables disappear discreetly into the downtube and fork for outta sight internal routing that keeps the lines and silhouette clean looking, and on the practical side, eliminates a small possibility of a cable snags and paint scratches that could occur with externally routed cables.

The headset is a 1-1/8″ top bearing tapering out to a 1-1/2″ bottom bearing, providing maximum stability to anchor fork flex.  The smaller top upper bearing saves a few grams, and proves the Look engineers are paying attention to shaving weight wherever they can.

Down low and up close the bottom bracket junction is massive.  This is nothing new as it’s become standard issue on performance level bikes – it’s a logical evolution of carbon technology and frame design – bigger tubes for maximum strength, stability and efficiency, but with the light weight that carbon offers.

Both the front and rear dropouts are designed around Mavic’s Speed Release through axle, which allows you to remove either wheel without pulling the axle all the way out.  For this build – we stayed with a lean and sleek bolt-through mount (vs a levered axle), which requires just a 6mm allen key to unscrew the axle from the right side, allowing the axle to slide part way out of the drop – enough so the left side mount disengages, and the wheel simply drops out.

The axle stays in place in the hub, so you don’t have to worry about losing it during a trailside fix.  The rear axle unscrews from the non-drive side, which makes sense to keep the work zone away from the clutter of the drive-side.

Now back to the frame…

The rear stays are purpose shaped for tire clearance, stability, and comfort.  And that’s the beauty of carbon fibre frames today – shape really does matter when it comes to ride quality, and carbon fabrication allows for pretty much any shape the engineers wish for.

The seat stays are flattened right where you can read the “3D Wave” graphic on them which adds a small amount of vertical flex for a more comfortable ride.  The chainstays are also shaped to anchor the rear wheel within the drive-force dynamic – all while offering as much pedal / shoe clearance on the outside, and chainring & tire clearance for 650×2.1 tires.

The chain stays are also asymmetrically shaped.  The non-drive side is a straight line from the bottom bracket to the rear axle, but the drive side drops down just behind the chain ring to allow for better chain clearance in the smaller gear ratios.

And that cable we saw disappear into the frame at the headset…?  They emerge just where needed at the business end to connect to the rear disc brake – and there are channels on both the brake and derailleur sides if you prefer to run mechanical shifters.

WHEELS – CORIMA G30.5 Carbon Tubeless – US $2,200

The growth – and let’s even call it maturity – of adventure riding has drawn up the development of more specialized gear all around the bike – of course including wheels.

Finding a place somewhere between road and mtb wheels – all the major brands now offer hoops specific to all-terrain riding – with wheels built to new standards of lightness & strength.  Enter Corima’s semi-deep section 30.5 carbon wheels – built specifically for all-road type riding.

The Corima brand has been around for over 30 years now, you might remember their original 4-spoke carbon wheel design, and even seen their wheels rolling under road stars like Chris Boardman and Laurent Fignon.  They’ve fabricated in carbon for years, including full bikes, so they know what they’re doing.  And if geographic location means anything to you in terms of production preference, Corima wheels are made at their own factory in France.

On closer inspection, you’ll notice what appears to be a second valve placement in the rim.  In fact this is part of what Corima calls its “Over pressure protection system”.  It’s actually a release valve that allows excess air to escape the internal rim cavity if/when the rims have been over pressurized during inflation and if air leaks around the valve core or rim tape during initial setup.

The basic info on the G30.5 wheels are:

  • Rims are 30.5 mm width (internal width of 22mm)
  • Will take tire widths from 28mm up to 60mm
  • Rims use their Internal Foam Core Overpressure Protection System
  • 1560g weight for wheel set
  • 24 spokes front & rear
  • 5 bar max. tire pressure

The Pirelli Cinturato Gravel H tire looks great in their “classic” brown sidewall color.  The low tread pattern is well suited to a mix of hard pack and loose surfaces, and makes perfect sense when you hit the pavement for a stretch too.

Design & Construction
What stands out here is what you can’t see from the outside – and what adds strength to these wheels.  The internal cutaway below shows two things of note:

  1. The I-beam support structure that runs from side to side inside the rim, which adds both sidewall strength, and diametrical strength to prevent the wheel from collapsing as it rolls over bumps.
  2. That foam core you see – is super light, but actually adds structural strength and support from the inside.

Hubs and spokes are by DT Swiss – renowned specialists in building the center portions of the world’s best wheel sets.  Each wheel uses 24 spokes, which offers enough strength that you’ll really never have to worry about busting something out in the wild.  Even if you do there’s enough extra built in that getting home on 23 spokes should not be a worry.

Visually, the wheels look really cool – deep section 3K carbon weave – they stand up nicely shorn with a big variety of rubber – although Corima does offer its recommended tire choices on the website, based on who they consider is making the best tubeless rubber for adventure riding.

Once I start riding higher air volume tires, the plushness of the ride tends to hide the true value of the wheel stiffness.  I’ve been running these around 35-40 psi, which is enough pressure to roll fine of pavement and hardpack, but still offer some plushness on the trail.  The wheels themselves provide a solid, stiff platform to anchor the tires, so that the tires can do their job.  This is my first experience with Corima wheels, and after about a dozen rides, they have performed flawlessly.

Drivetrain
The gruppo is SRAM Force eTap AXS – drivetrain, shifters, derailleurs and brakes.

While SRAM offers a 1x option (which has been around for a few years now), I personally prefer the gear ratio options offered with a 2x chainring setup – I need the extra gears around here, and I also like how it offers a little bit straighter chain line over the range of gears I use.

Rear cassette is SRAM Force eTap AXS XG-1270 –  10-33t- (also comes in 10-28, and 10-36), which mated to the 43/30 from dual chainring setup makes for more than enough gears to climb just about anything I’m up for.

The Flat Top chain is designed to be a bit stronger, thanks to the physics of more material across the top line of the chain.

Overall drivetrain performance has been flawless.  Long gone are the days when SRAM first entered the market and we complained about their noisy cassettes.  Their drivetrains have been through multiple iterations, renovations, and permutations, to a point now where they perform at the top of the class, and these improvements carry all the way down from Red to Rival, eTap to mechanical.  Shifting on the backend is quick and precise.  The front end shifting (which used to be a split second slower than it should), also feels better, thanks largely to improvements in their chainring designs, and shift ramps.

Upon initial setup, I did have a tire clearance issue in the rear, where the 40mm Specialized Rhombus skins actually made contact with the brace-plate on the back of the rear derailleur.  Luckily the kit comes with 3 brace-plates of different sizes, so we just swapped in the “medium” sized version.

I’ve been riding long enough (and am fortunate enough) to remember back to the 1980’s and what lever design was like back then.  Remember those tiny brake hoods, barely enough to hold onto – early versions didn’t even consider the “tops” to be an actual place hang on.

Thankfully modern lever design has gone fully ergonomic – and I still recall seeing SRAM’s first iteration of hydraulic road levers and how much bigger the tops were they versus typical mechanical tops of the day.  Obviously they need to be a certain volume to hold the brake fluid reservoir in there, and when I first grabbed onto one I felt how much comfort – and better control – this larger size offers.

That big knob is really a great platform to drive the bike from.  There’s plenty of real estate to hold the hoods in a few hand placements, and enough to grab on to for solid control.  The rubber is grippy, and the perforated design on top helps the hands stick in place.

The levers are shaped for both comfort and purpose – the “S” curve shape allows for a powerful pull from both the tops using middle, ring and baby fingers, as well as from the drops using the first and middle fingers.  The reach is also adjustable to fit hands of all sizes.

Shifting is controlled by two small paddles hidden behind the levers. Tapping the right paddle inwards moves this chain on the rear cassette out and away from the wheel, to access a taller gear. Tapping the left paddle inwards moves the chain inwards when you want easier gears – like for climbing.  Tapping both paddles together shifts the front derailleur back and forth between the two chainrings.

Setting up the system is pretty easy, and done using the SRAM AXS app (which also connects Quarq and Rockshox products), and allows basic things like pairing levers to each derailleur, how many gears each shift will jump, setting multiple bike profiles, tracking ride data, and updating to the latest firmware to ensure best possible performance, and a bunch more features.

The whole system has been perfected and works like a charm.  Shifts at both the front and rear are precise, solid, and truly better than if I were doing my own shifting on a mechanical system.

The seat tube secures in from the top – clean and outta sight.

Handlebars are Zipp Service Course SL-70 XPLR model, designed for gravel riding with features like a shorter 70mm reach and shallower 115mm drop, making them easier to find the various holds – tops, hoods, drops, and more allowance for moving back on the bike – something we tend to do more of when riding off-road.

The tops offer a 3 degree bend back towards the rider, which felt great in my hands when gripping the tops.  The drops feature a nice outward bend that actually widens the bars from 42 cm C-C to the top, to about 47cm wide at the bar ends.  It makes ’em easier to find, and easier to control the bike from if you like riding the rough stuff from a low position.

Bar tape was a ‘natch from Lizard Skins,  but  gold / champagne is not the most widely offered color either.   I’ve used the Lizard Skins tapes before and they were a perfect fit for a high-end build like this.  They offer 3 different thicknesses of tapes – I went with the 2.5 mm version (also offer e a 1.8mm and 3.2mm versions).  Being a long time roadie, and given the decent girth of the Zipp bars, the 2.5 felt right for the size of my hands and still offers enough padding to absorb more of the rough trail stuff.

Lizard Skins tapes are two-ply design, with a spongey foam on the bottom to grip to the bars and absorb shock, bonded to a sticky top layer for good grip.  They recommend NOT stretching and pulling the tape as you wrap it, since this can cause the bonds to separate.

Quick sidebar about Lizard Skins…   Most of us remember Johnny Hoogerland’s horrific crash at the 2011 Tour de France when he and Juan Antonio Flecha were brought down when a car overtaking their five-man escape group swerved right to avoid a tree after executing an irresponsible overtaking manoeuvre on the grass verge.   He was such a good sportsman about the crash that fans started supporting the team’s sponsors – one of which was Lizard Skins – and all of sudden tape sale took off.

 

Moving to another all-important point of contact – I’m running the Cadex Boost saddle.  Cadex – in case you aren’t familiar with the the brand – is owned by Giant, but dedicated to bringing high-end, high performance gear to market.  So far they offer wheels, tires, this saddle and handlebars… all key touch points and upgrades that can dramatically alter the ride of any frame set.

The Boost saddle is a three piece construction, using Cadex’s very deep knowledge of carbon production to develop a saddle that combines flex in the rights places for comfort, with stiffness in the right places to ensure pedalling power is not lost or absorbed into the saddle, and instead is transferred down your legs to the drive train.

Ewan Campbell, Global Product Marketing for CADEX, explained to me: “that although the experience with carbon manufacturing certainly comes from the broader Giant Group, the willingness to push boundaries with the material is really what differentiates CADEX. In this particular case it would be using Advanced Forged Composite Technology, a technology first introduced on the robust rocker arms of Giant and Liv full-suspension mountain bikes, to cold-forge the base of the CADEX Boost saddle into a thin, complex and ultralight shape that no-one else had considered before.”

The rails and base are carbon fibre.  The rails (ovalized vertically to reduce flex) are shaped to connect with the base in a wider shape to disperse impacts, and placed where your sit bones aren’t – so you won’t get that jarring feeling going right “up yer arse” like other saddles can.

The rear of the saddle tips up slightly, forcing the rider forward into a more aggressive pedalling position.  Comfort is very good.  The padding under the sit bones area is dense enough to absorb bumps, and soft enough to be comfortable.  The open channel down the middle distributes rider weight away from the perineum, to aid in avoiding numbness on long rides.

cadex boost saddle cutaway showing eptu particlesAnd in case you’re wondering what “Particle Flow Technology” is – it’s basically a pocket of these tiny polymer particles located inside the seat-pad more or less where your sit-bones sit.  Think of tiny bean bags inside the saddle – when you sit on em they shape perfectly to you.  Then they rebound to the original shape when you leave the saddle, all the while adsorbing impacts and adding comfort.  My experience has been a good one – the saddle fits me well, and is comfortable.

There’s also a tiny mounting bolt at the back to add a variety of peripheral attachments – light, fenders, saddle bags etc.

Finally, it’s light too – around 140 grams, and will run you around US$300.

Accessory Mounts
All of my rides so far have been shorter out and back jaunts, 1-3 hours in length.  But for those who like to travel further, you gotta be able to take gear with you. The 765 has six different placements for add-on bottle and gear mounts around the frame – on the top tube just behind the headset, on the downtube – 1 under and 2 on top, the seat tube – 3 bosses in front.  Then you can add gear around the saddle, handlebars with after market bags if you still need to.

LOOK X-Track Race Carbon Pedals – $140

Look’s X-TRACK RACE CARBON pedal claims the “best power-to-weight ratio on the market today“, and what better pedal could I think of as part of this build?   That massive platform and it’s huge contact area allows more efficient transfer of power from you to your drive train.

I can attest to the big contact patch being easier to find when clipping in.  I also like the dimpled surface that adds grip for stability where shoe meets pedal – it works and there’s something confidence inspiring about a beefier looking pedal.

That bigger platform can also add comfort by reducing hotspots since pedal pressure is spread over a larger area.  That’s physics, and it works.

Look has been perfecting carbon for years now – allowing them to build a very strong pedal set that weighs in a 356 grams – and that’s light.  Tension  (+/-) is adjusted with an easy to reach 3mm allen screw.

The mechanics are top notch too with two sealed cartridges per side running steel bearings.

The X-Track pedals also come in 3 other flavors to suit your budget – the

RIDE IMPRESSIONS
As gravel / all road / adventure riding emerged (before it exploded) onto the scene, it grew out of a place for people to access cycling, or find new ways to ride their bikes from a bunch of different access points.  From my vantage point as an OG mountain biker (c. 1982), then evolving into a mostly- road rider (around 1986 when I bought a Pinarello Montello), I’ve always liked riding (of course did bmx as a kid).  So I was intrigued by the chance to enjoy a bike that could take me a lot more places than I’d go on a pure road bike.

In recent years, exploring all-road riding has included cycling into the wilderness at events like the Peter Sagan Gravel Fondo, or an epic 120km point to point adventure in Idaho at a product launch a few years back.  From pedalling through majestic scenery on an hours-long ride, to something much closer to home like a 45 minute “executive loop” around PEZ HQ connecting some of my favorite climbs with trail, dirt road or unpaved pathways on a bike that I don’t have to worry about breaking, I do like it all.


Cages and saddle bag by ArundelBike.com – their classic, and always working “Dave-O” cages.

There’s a noticeable difference to riding an “all-road” bike that’s inherently more fun than riding a dedicated “road” bike.  Sure, nothing beats the rush of speed on a road bike – but all-road offers up an unbeatable freedom to go anywhere, and not be penned in by road surface.

There’s the sense that this bike can take a lot more punishment.  I’m not as picky about my line through rough stuff now that I’m on a bike with bigger tires and sturdier wheels, disc brakes, and slightly more forgiving geometry.  It’s more fun to just hammer the rough stuff.

The slightly slacker front end (70 degrees on my size Small) of the 765 allows for more stability in the trails and rough stuff, and descending – better control than a steeper road geometry would.  While the steeper seat tube angle – 74 degrees on my tester, keeps the juice going into the drivetrain, and adds to a faster feel both accelerating and climbing.

Couple this with the lighter weight – my bike weighs just a hair over 20 lbs, with cages and pedals, and the possibilities for adventure expand yet again.  Fine tune the whole cockpit with handlebars with a slight flare out at the drops and my road-centric fixation with style and speed slips out of the picture to be replaced by the simple joy of bombing around on a bike.

I’ve set mine up with a slightly higher handlebar position than my road bikes, but nothing major.  I don’t really ride in an aggressive position anyway, so a couple of cm difference in the saddle to bar tops height isn’t noticable, but does make it slightly easier to reach the drops in the case that I’m grinding out a long flat section into the wind and just want to save as many watts as possible.

All the off-road riding around PEZ HQ features some pavement to get to / from where I’m going – so I like how this bike feels close enough to my road bikes that I still feel fast on the unpaved stuff, and it hustles along at speed without feeling like I’m pushing a tank.  The light weight is a bonus too – keeping the whole package close enough to my road setups that I still feel fast.

Living at the foot of Vancouver’s north shore mountains – I have instant access to some pretty good climbing.  One ride I’ve been doing lately involves 400m of climbing in a 15km/ 45 minute loop – good for an end of day “relaxer”.   4km of that is up a gravel pathway with pitches up around 15% in places – it’s a grinder.  But it’s also a great test track for key aspects like climbing and descending.  My fit on this size Small tester with its 52.4cm length top tube has my seat pushed back on the rails and a 110mm stem mounted to complete my fit.  That puts my weight well back over the rear wheel, coupled with the snug fit of the rear wheel close to the seatpost makes for some very nice climbing power and grip.

Look’s race bred geometry is evident in the 765, and for me, coming from the road side, I like the fast responsive feel of this bike overall.  It feels close enough to my road set up that this feels less like a different geometry and more like I’m riding my road bike off-road.

The SRAM eTap AXS Force 46/33 and 11-33t cogset has worked flawlessly.  Shifting is smooth and precise, and the gear ratios allow me to climb a 15% gravel grade (albeit grunting it out), and them dive bombing a 13% paved descent with enough top end that feels like it will take me faster than my comfort zone allows.

This has been a fun project build – but I suspect the real fun is still ahead as warmer days and bigger rides are just around the corner.

You can reach me with questions here:  manager at pezcyclingnews.com

 

Look 765 Gravel RS Project Build Specs

Weight as Tested: 20.6 lbs, with Look pedals, cages, small saddle bag and rear light
Frame: Look RS carbon fiber, dropped chainstay, 12mm thru-axle, flat mount disc
Fork: Carbon Fiber with carbon steerer: 1 ⅛” -1 ½”, 12mm thru-axle, flat mount disc
Shifter/Brake Levers: SRAM eTap AXS Force 2x , 12-speed
Brakes: SRAM Force 1 hydraulic, Centerline rotors 160mm front, 160mm rear
Crankset: SRAM Force
Chain Ring: SRAM etap AXS Force 46/33
Cassette: SRAM Powerglide PG-1170, 11-33t
Wheels: Corima G30.5 Carbon tubeless clinchers
Tires: Specialized Rombus & Pirelli Cinturato Gravel H
Stem: 110mm Look LDS aluminum stem,
Bars: 42cm Zipp Service Course SL-70 XPLR
Seatpost: Look LS2, carbon, 27.2mm diameter
Saddle: Cadex Boost
Pedals: Look X-Track Race Carbon
Warranty: Lifetime, frame and fork
Country of origin: Taiwan
More Info: lookcycle.com

 

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