In the past, a road bike being lightweight was a racer's primary concern. Such was the obsession that in cult book The Rider, Tim Krabbé recounts being told by another cyclist that, "Anquetil always moved his water bottle to his back pocket during climbs, so his bike would be lighter."
But the contemporary fashion for 'aero is everything' might, at first glance, make lightweight bikes seem like a bit of an anachronism, but there are actually still a number of sound reasons why you should consider one as your next bike.
On the limit
With the UCI weight limit seemingly stuck at 6.8kg, 'lightweight' has been largely defined at that point, and brands have been able to focus their attention on improving other areas of the bike, instead of simply chasing grams in a race to the bottom (although, naturally, that is still a thing).
Where aero bikes often have to make compromises on things like handling, ride quality, fit and user-friendliness in pursuit of all-out speed, lightweight road bikes have tended to become the all-rounders of road cycling, with development focused more on these important, but often undervalued, characteristics.
Such are the improvements in these areas that many WorldTour pros still choose to ride lightweight bikes over their sponsors' aero-bike offerings, despite the apparent penalty in aerodynamic efficiency.
Where it counts
The data tells us that aerodynamic bikes are faster on flat and rolling courses, but let's be honest – the hills are still where it really counts. The important Strava segments are, generally, not boring sections of flat or rolling road, they’re hills, and, on the proper hills, lower weight still beats aerodynamics.
One relatively recent development is the appearance of disc brakes on lightweight climbing bikes. Rim brakes have long been favoured because of the difference in weight, but the gap has narrowed considerably, and it's worth considering that what goes up must also come down.
You might appreciate the improved power, consistency and modulation of hydraulic disc brakes when you're coming back down that 20 per cent hill, with your heart rate pushing off the scale after a full-gas KOM attempt.
Perhaps more crucially, lightweight bikes still retain the power to impress your friends or family members, because weight is tangible. Show them an incredibly expensive aero bike and the first thing they'll do is pick it up and complain that, "It's quite heavy… How much did you say this cost?"
By the time you've started explaining that "over a typical 40km rolling course, performance modelling shows that this bike is 45 seconds faster at 50kph than an equivalent lightweight bike…" they'll likely have lost interest and wandered off, thinking that you got royally ripped off.
A lightweight bike provides an obvious tangible difference, and, sometimes, that provides a greater psychological benefit than the few intangible seconds offered by manufacturers.
Unsurprisingly, carbon fibre dominates the scene for lightweight road bikes. Its unique, tunable characteristics make it the perfect material for making light and stiff bikes that excel when pointed uphill. The downside is that these lightweight frames and components tend to come at an exorbitant cost.
As the great Keith Bontrager once said: "Strong, light, cheap. Pick two." That said, If the UCI limit is what you're looking at, you don't necessarily need to buy the top-of-the-range model these days, which will often actually be lighter than the UCI's minimum weight limit. Some brands are even able to offer builds with Shimano Ultegra that can still hit the 6.8kg benchmark; just don't expect them to be particularly cheap.
Read on for Cyclingnews' round up of the best lightweight road race bikes available to buy this year.
BMC Teammachine SLR01 Disc
Tour de France winning bike design that seems to have inspired almost every other brand in 2019
Price: £12,500 | Weight: 7.06kg | Brake: Disc | Frame: Carbon | Sizes: XXS-XXL
Dropping the seat stays for improved comfort and aerodynamics has been a 2019 bike-design must-have, but the BMC commitment to progressive bicycle design is such that they debuted this feature back in 2010 on the Teammachine.
The combination of massive pedalling stiffness from the oversized down tube and bottom bracket area, combined with the comfort gained from thin, dropped seat stays, made this design a winner from the start. Cadel Evans promptly rode to victory in the Tour de France only a year later, in 2011, and it continues to be the bike of choice for most riders at Dimension Data, thanks to its blend of efficiency, comfort and perfectly balanced handling.
With the addition of hydraulic disc brakes, a semi-integrated cockpit system (that still retains adjustability for both fit and maintenance) and updated cable management, the 2019 Teammachine is more evolution than revolution, but this just shows how advanced the original design was at the time. There's little about this bike that looks out of date.
We'd perhaps like to see a nod towards more aerodynamic tube shapes on future models, but the only real downside is that you'll need extremely deep pockets to get hold of one.
Boardman SLR 9.8
Excellent value road racing package from the household British name
Price: £5,700 | Weight: 6.8kg | Brake: Rim | Frame: Carbon | Sizes: XXS-XL
Ever since his iconic Individual Pursuit triumph at the 1992 Barcelona Olympics, aboard the Lotus 108, Chris Boardman has been synonymous with progressive bicycle design. You might not be aware, however, that Mr Boardman was also a four-time British National Hill Climb Champion (he had an unbeaten run from 1988-1991), so he also knows a thing or two about climbing bikes.
The Boardman SLR 9.8 is the eponymous brand's flagship model, using their highest grade of carbon fibre to deliver a stiff, lightweight frame. Dropped seat stays and room for 28mm tyres also mean you get impressive comfort for a super-stiff climbing bike, while its truncated aerofoil tube shapes promise efficiency across all terrains.
Whilst the frameset might not be WorldTour-proven, you do get a quality set of branded components (a rare thing in these days of integration and in-house brands), including Zipp 202 Firecrest clincher wheels paired with Vittoria Corsa G+ tan-wall tyres, Zipp Service Course SL finishing kit, SRAM Red eTap and a Fizik Antares R3 saddle with carbon rails.
All of this adds up to a bike that can rival anything on the WorldTour, but the true ace up its sleeve is its price. Whilst not cheap by any measure, it does represent great value for money compared to most of its peers.View Deal
Cannondale SuperSix Evo Hi-Mod Disc
Progressive aero update to one of the most acclaimed WorldTour climbing bikes
Price: £9,500 | Weight: 7.49kg | Brake: Disc | Frame: Carbon | Sizes: XS-XXL
With its renowned blend of low weight and enormous stiffness, the Cannondale SuperSix has long been considered one of the best bikes for climbing, but its round-tubed design was admittedly getting a little long in the tooth.
The SuperSix 2020 brings a complete design overhaul, with truncated aerofoil tubing, a sleek integrated cockpit and system designed wheels. The SuperSix maintains the glorious pedalling efficiency, low weight and razor-sharp handling, but dropped seat stays increase comfort and hydraulic disc brakes bring improved braking control and tyre clearance.
Now arguably more of an all-rounder than just a pure climbing bike, the Cannondale SuperSix does sit a few hundred grams over the UCI weight limit, but the aerodynamic gains will likely offset this on less steep climbs.
The only let-down is the activation fee for the Power2Max integrated power meter. It's brilliant that the bike comes with one of the market's best power meters already installed, but considering how much this bike costs, it's a little annoying that you have to pay an extra $490/€490 to access its full potential.
Canyon Ultimate WMN CF SLX Disc 9.0 Team CSR
Great value, super-efficient climbing bike with women specific geometry and components from the German online behemoth
Price: £5,449 | Weight: 7.2kg | Brake: Disc | Frame: Carbon | Sizes: XXXS-M
The women's specific version of Canyon's Ultimate, this is the same bike that Canyon-SRAM use.
Changes to components and geometry are the primary differences between the men and women's framesets, but Canyon also claims the women's frameset is lighter and more aerodynamic than the men's version.
An Ergon SR1 Sport saddle, developed in partnership with the multi-discipline World Champion, Pauline Ferrand-Prévot, tops the eye-catching Canyon S14 VCLS seat post (which features a split-tube, carbon leaf spring design that offers up to 20mm of travel), for brilliant comfort through the most important contact point.
Thanks to the partnership with Canyon-SRAM, the paint job is a little more exciting, but again, there's unfortunately not much choice.
Still, the Canyon Ultimate WMN CF SLX Disc offers fantastic value for money, offering top of the range performance and kit at a price far below what most other brands can provide at this price point.View Deal
Cervelo R5 Red eTap AXS
A no-compromise climbing bike that hides its performance credentials behind classic looks
Price: £7,299 | Weight: 6.9kg | Brake: Disc | Frame: Carbon | Sizes: XS-XXL
The bike of choice for former Giro d'Italia champion Tom Dumoulin, the Cervelo R5 is a bit of a wolf in sheep’s clothing. It would be easy to look at the traditional frame shape and assume it’s a vestige of a by-gone era (especially compared to wild aero design of the Cervelo S5 Disc), but you’d be far from the truth.
The Cervelo R5 is built from Cervelo's Squoval™ Max aerodynamic tubing, tuned to balance phenomenal levels of stiffness with low weight, whilst a stable yet racy geometry and hydraulic disc brakes offer confidence-inspiring handling. It also has clearance for 30mm tyres, so if you want more volume for grip and comfort on rough roads, this bike can handle it.
Up front, Cervelo specs its own carbon stem and handlebars. There are nods to aerodynamics here, but Cervelo hasn't yet gone down the route of full S5-style cockpit integration with the R5.
This invariably means a small aerodynamic penalty, but it does also mean you can easily change the stem length or handlebar width to suit your personal fit requirements – something that might not be possible with a fully integrated system.View Deal
Giant TCR Advanced SL 1
An evolution of the original compact road frame design – if it ain't broke, don't fix it
Price: £4,990 | Weight: 6.8kg | Brake: Rim | Frame: Carbon | Sizes: S-L
It was legendary bicycle engineer Mike Burrows (designer of the Lotus 108 and 110 bikes) who created the Giant TCR's compact frame design, in the mid-90s. Back then, among a sea of bikes with horizontal top tubes, it represented a radical departure from the norm, but it proved to be a winning design and spawned countless copies.
The 2019 TCR encompasses over 20 years of refinements on the original design, but the fundamentals remain the same; the compact frame triangles make for an impressively stiff and lightweight frameset. Tubes are shaped to maximise stiffness to weight, rather than aerodynamics, meaning this is a true climbers bike. The frameset is so lightweight that even a build with Shimano Ultegra R8050 Di2, Giant Power Pro integrated power meter and 42mm SLR-1 Giant carbon wheels can hit the UCI weight limit of 6.8kg.
The OverDrive 2 oversized fork and massive Contact SLR carbon stem make for remarkable steering stiffness, which translates into wonderfully precise handling out on the road. Giant retains a separate handlebar and stem setup on the TCR, which trades off the aerodynamic efficiency of an integrated design (such as that found on the Giant Propel), for the adjustability and user friendliness that a traditional setup offers.
The only minor niggle is that the integrated aero seat post can make the frame a bit of a faff to travel with, and potentially limits the frames resale value, as you can have to cut it down to match your own specific saddle height, and there's only a limited range of adjustability from there.
Liv Langma Advanced Pro 0
A Giant TCR redesigned from the ground up for the needs of women racers
Price: £4,299 | Weight: 6.8kg | Brake: Rim | Frame: Carbon | Sizes: XS-M
Liv is a subsidiary of Giant, so the Langma naturally shares much of its DNA with the TCR. The bike of choice for riders like Marianne Vos and Ashleigh Moolman Pasio of CCC-Liv, it carries across both the compact frame design, that offers an amazing blend of stiffness and low weight, and the OverDrive2 fork plus Contact SLR Flux carbon stem combination that provides massive steering stiffness for precise handling.
Where the Langma departs from the TCR is in its more progressive tube shapes - whilst the TCR still has boxy tube shapes, the Langma sees the introduction of aerodynamically tuned down tube and seat tube shapes, bolstering its allrounder potential.
Like the Giant TCR, the Liv Langma frameset is so light that even the Advanced Pro frameset, which comes with a standard aero seatpost (rather than the integrated seat post found on the Advanced SL models), can be built up to hit the UCI weight limit with Shimano Ultegra R8050 Di2, a Giant Power Pro integrated power meter and 30mm SLR-1 Giant carbon wheels.
Unfortunately, the Liv Langma is only available in three sizes (XS-M), so if you're particularly tall, you might need to look elsewhere (Giant recommends its size M is suitable for riders up to 5'11" tall, with a 31" inside leg length).
Specialized S-Works Tarmac Disc
Hugely popular, multiple Grand Tour winning climbing bike, now more aerodynamic, more comfortable and with disc brakes
Price: £9,500 | Weight: 6.8kg | Brake: Disc | Frame: Carbon | Sizes: XS-XXL
The latest version of Specialized hugely popular Tarmac retains the fantastic efficiency and handling we've come to expect, but goes and slows faster than ever before.
Time in the Specialized Win Tunnel has led to dropped seatstays and redesigned tube shapes, that Specialized claims make the new Tarmac as aerodynamic as the original Specialized Venge, even with the addition of hydraulic disc brakes.
It's pricey, but you do arguably get a lot for your money. Specialized specs its own components and wheels, but in every case these arguably rival or surpass offerings from dedicated component brands. You get a set of Specialized's S-Works Power cranks, a carbon railed S-Works Toupé saddle, carbon handlebars and the Roval CLX 50 Disc carbon wheels come tubeless ready, with CeramicSpeed bearings and Specialized Turbo Cotton tyres.
Specialized makes a big deal about the fact that each frame and fork size in the range is built with their Rider-First Engineering design, which means each size gets specific carbon layups and fork tapers, so that ride quality is maintained across the board.
Unlike some other brands, however, Specialized has decided that gender-specific geometries aren't actually necessary, and instead specs different contact point components and crank lengths on it's women's specific builds. It's hard for this writer to say whether that's the right approach, but it seems to work just fine for the riders of the Boels Dolmans Cyclingteam.
Trek Emonda SLR 8 Disc
A superbike designed in conjunction with legendary climber Alberto Contador, that’s now just as quick going down hills as it is at going up them
Price: £5,850 | Weight: 6.92kg | Brake: Disc | Frame: Carbon | Sizes: XXS-XXXL
Once a pure climbing machine, built to give Alberto Contador an ideal platform on which to unleash his infamous out of the saddle attacks, the addition of hydraulic disc brakes and clearance for up to 30mm tyres widens its potential remit considerably.
Coming with mechanical rather than electronic Dura-Ace 9100, and Bontrager’s mid-range Bontrager Aeolus Pro 3 Disc carbon wheels, the Trek Emonda SLR 8 Disc might not be the top of the range model, but it nevertheless only gives away 120g to the UCI weight limit. This is thanks largely to its superlight frame which is, rather incredibly, claimed to weigh just 665g.
If the Emonda gets an update for 2020, we could see tube shapes that are better shaped for aerodynamic efficiency (much like with the recently announced 2020 Trek Domane), rather than solely being optimised for the best stiffness to weight ratio, as this is the only area where it currently lags behind the competition.
Available in a wide range of sizes and finished with impressive components from Bontrager, all of Trek's bikes can be customised through their Project One programme. The options are extensive – from paint jobs through to practically every major component on the bike (though naturally, any upgrades will increase the overall cost) – so if the stock Radioactive Yellow/Trek Black paint job isn't to your taste, for example, you should still be able to find something to suit.
Wilier Zero SLR Disc
Thoroughly modern climbing bike from one of the oldest racing bike manufacturers in the world
Price: €11,100 | Weight: 6.8kg | Brake: Disc | Frame: Carbon | Sizes: XS-XXL
Despite their illustrious histories, Italian manufacturers are generally not renowned for being on the cutting edge of bicycle design. We tend to think of Italian racing bikes as beautiful, classic, perhaps even old fashioned – but the reality is that, with Wilier at least, this couldn't be further from the truth.
The Zero SLR Disc is the latest lightweight bike from Wilier. Borrowing design cues from their Centro10 Pro aero bike, it's a thoroughly modern climbing machine. It ticks all the boxes; a super lightweight carbon frame with truncated aerofoil tube shapes, integrated handlebars with fully hidden cables, hydraulic disc brakes, carbon wheels and clearance for 28mm tyres.
Its tried and tested geometry, and stiff frame and fork mean handling is great, and its clean lines and complete cable integration make it a real looker. Wilier is kind enough to offer some very nice paint jobs as well – matte black with white detailing, matte velvet red and a glossy admiral blue. The matte black frameset is slightly lighter, but go for the red or blue for that essential touch of Italian flair.
There's no denying that this is a pretty expensive bike – Wilier retains that classic Italian bike characteristic – but you're buying in to a European brand with over 100 years of experience in making bikes, and all of the racing heritage that comes with that.
As of yet, there doesn't appear to be any women's specific versions available, but, hopefully, that’s something Wilier will offer in the near future.View Deal
What do you think is the best UCI legal climbing bike currently on the market? Are lightweight bikes even still relevant in the era of 'aero is everything'? Let us know what you think in the comments below.
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