Giant TCR Advanced Pro 1 Disc 2021

Giant's TCR Advanced Pro 1 Disc is a lively and efficient road bike that boasts most of the aero features the new, top-level TCR Advanced SL gained earlier this year. The Shimano Ultegra-based parts package is impressive too.

Giant has given its lightweight TCR range an aero makeover for 2021. If you've not read our review of the top-level Giant TCR Advanced SL 0 Disc 2021, I urge you to take a look. Drama, intrigue, plot twists... you'll love it. More to the point, it's relevant to the Giant TCR Advanced Pro 1 Disc because a lot of the tech is carried over.

> Buy now: Giant TCR Advanced Pro 1 Disc 2021 from Winstanleys Bikes for £4199.00

The TCR Advanced Pro 1 Disc's frame is made from Toray T700 carbon fibre, whereas the TCR Advanced SL is 30% Toray T800 and the remaining 70% is a new, higher modulus filament that's said to be stiffer and lighter. The production methods are different too, but in many ways the two models are very similar.

You immediately notice the Advanced Pro Disc's tube shapes are mostly identical to those of the SL, for example. The head tube, down tube and fork all feature the same new tube profiles – truncated aerofoils that are designed, Giant says, to reduce drag at a wide range of yaw angles.

The trailing edge of each tube is cut off square to reduce weight, avoid handling issues in crosswinds, and stay within race equipment rules.

The down tube is designed to work aerodynamically with a water bottle in place, the majority of us riding with a bottle most of the time, after all. We've measured that tube at a whopping 65mm across at the widest point, which is about as wide as it's possible to go without interfering with the drivetrain.

The fork and seat stays sit well wide of the wheel and tyre, the idea being to improve airflow efficiency as well as increasing tyre clearance.

Nevertheless, there are noticeable differences between the tubes of the TCR Advanced Pro and the Advanced SL.

Most obviously, the Advanced Pro has a seatpost that slots into the seat tube, whereas the Advanced SL has an integrated seatpost (the extended seat tube is topped by a seatmast, negating the need for a post), while the seat stay yoke is slightly lower on the Advanced Pro.

Even here, though, the Advanced Pro's seat tube and Variant composite seatpost feature truncated aerofoil tube shaping.

These relatively minor differences mean Giant's aero claims Giant for the Advanced SL don't apply to the Advanced Pro. The Advanced Pro's performance in the wind tunnel is unlikely to be vastly different, but we can't put figures on it.

(For what it's worth, Giant said the TCR Advanced SL Disc was marginally more efficient than the Specialized S-Works Tarmac Disc and the Cervelo R5 Disc, and significantly more aero than the Trek Emonda SLR Disc, although both the Specialized and the Trek have been updated recently; find out about Giant's claims here).

You can't feel aero improvements either, but you can feel the TCR Advanced Pro 1 Disc is a lively performer that responds well as you increase the power. It isn't quite as stiff as the Advanced SL, but it's pretty close.

According to Giant's own figures, the Advanced Pro's pedalling stiffness (at the bottom bracket) is 88% that of the Advanced SL's. The torsional stiffness is 92%, and the lateral stiffness at the fork is 79%.

Would you notice the difference? If you sprinted on them back-to-back you might. Otherwise, probably not. Although the Advanced Pro lags a little behind the Advanced SL in terms of rigidity, we're comparing it with one of the stiffest race bikes out there.

You certainly aren't left feeling the Advanced Pro is in any way flexy. Far from it. It feels solid and offers rapid acceleration.

The TCR Advanced Pro 1 Disc is built to exactly the same geometry as the TCR Advanced SL 0 Disc, so in terms of fit it's like getting back on a familiar bike.

I rode the L version with a 580mm top tube, 530mm seat tube (short because of Giant's compact frame design) and 185mm head tube. This size has 73° head tube and seat tube angles, a stack of 581mm and a reach of 402mm, giving a stack/reach of 1.45.

Giant has tweaked the geometry of the TCR with this latest incarnation, but only slightly. The bottom bracket drop (the vertical distance the BB sits below a line between the hubs – see more here) has been increased by 2mm to take account of larger tyres; these lift you slightly higher off the ground, so increasing the BB drop moves you earthward again.

The disc brake TCRs have room for 700C x 32mm now, although 25mm tyres are fitted as standard. Various other measurements have been revised so that stack and reach, measured from the bottom bracket, remain unaltered. Giant has changed things to keep them the same, if you know what I mean.

Oh, there is one other significant change, but that's to the sizing. Whereas the ML model was previously closer to the L size than to the M, it now splits the difference between the two.

As you'd expect, the TCR's geometry is race focused, but it's not unusually aggressive. My L-sized bike was fitted with a 110mm stem and a Giant Contact SL handlebar with a 44cm width (measured centre to centre) and I could easily get into a flat-backed 'attack' position that felt efficient.

As usual, you can play around with headset spacers to get the front-end height right, and you could swap the stem, although your options are limited because Giant uses its Overdrive 2 system here with a fork steerer diameter that tapers from 1 1/2in at the bottom to 1 1/4in at the top.

Giant uses the same sizing on the TCR Advanced SL bikes to increase stiffness, although the more affordable TCR Advanced bikes have a more common 1 1/4in to 1 1/8in design.

I can't say that aftermarket stem compatibility bothers me hugely. Giant offers the aluminium Contact SL stem in a flipflop design with +/-10° rise and lengths from 70mm to 130mm. That should cater for nearly everyone. If you have unusual requirements or you wanted to swap to a particular model from another brand, though, you could struggle.

Components

I won't go into massive depth on the Shimano Ultegra groupset because we've reviewed it separately, but it's excellent kit with hydraulic disc brakes providing loads of one-finger control.

Giant specs a 52/36-tooth chainset with an 11-30-tooth cassette, which is a great choice for a bike of this kind, allowing you to mix it with your fastest mates when sprinting for signs, and still drag yourself up the toughest gradients when your legs are about to pack up for the day.

One major feature that's not immediately obvious is the Giant PowerPro power meter integrated with the chainset. It's a double-sided device – it measures power from both legs – that adds just 32g and has a claimed power range of up to 3,000 watts. That's way higher than any of us will ever hit. Giant claims +/-2 % accuracy at 150W/80rpm.

Bought separately, a Power Pro Ultegra R8000 power meter costs £799.99, compared to an RRP of £254.99 for a standard Ultegra chainset. Stay tuned for a separate review on road.cc soon.

If you don't feel the need for a power meter, or you already own one, the TCR Advanced Pro 2 Disc comes without for £3,199, although you step down a groupset level to Shimano 105. Paying £600 more for this TCR Advanced Pro 1 Disc looks the better deal.

Wheels

The Giant SLR-1 42 Carbon Disc wheels demand attention because, although pretty understated, they perform extremely well.

You might see they're in-house wheels and assume that means they're cheap and cheerful placeholders. Nuh-uh! This is a seriously good wheelset that has been updated for 2021.

You get 42mm-deep hookless carbon rims with an inner width that’s now 19.4mm, and an outer width of 23mm. Giant says that its Finite Element Analysis (FEA) has allowed it to put material only where it is needed, making the structure robust while minimising weight.

Giant also says that the hub internals have been precision machined to eliminate excessive bearing load and reduce wasted power.

The wheels offer loads of lateral stiffness that you notice when sprinting, and they’re well over 100g lighter than previously at just 1,452g. For comparison, Bontrager’s 30mm-deep Aeolus Pro 3 TLR wheels are 1,600g.

They come with 700C x 25mm Giant Gavia Course 1 tyres fitted, set up tubeless and ready to rock. The tyres use a carbon and Kevlar bead rather than a Kevlar-only bead, the idea being that it won’t stretch under heavy loads and so reliably keep air inside and hold the tyre on the rim.

The tyres roll fast, grip hard in the corners, and come with a Kevlar Race Shield puncture protection layer to help you keep rolling (sealant inside the tyres will hopefully deal with most punctures).

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Some brands spec relatively low grade wheels and tyres on bikes of this price, figuring you're likely to take them off and fit your favourites anyway. Giant hasn't done that, going with a really impressive setup that helps the bike deliver a responsive performance from the off.

Other stuff

As mentioned way back, Giant's updated Variant composite seatpost is designed to reduce drag, and it's topped by a Giant Fleet SL saddle. Liam is reviewing this saddle separately for road.cc.

Like the Fleet SLR on the TCR Advanced SL 0 Disc, this is a short saddle – 248mm from nose to tail – with a large central hole, and it uses Giant's Particle Flow Technology.

This means that separate pockets within the saddle contain 'high-elastic, free-flowing particles' that are designed to distribute pressure across a large contact area. It works. At least, it works for me and – spoiler alert! – it works for Liam too.

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The difference between the Fleet SL (£69.99) and the Fleet SLR (£129.99) is the material used for the rails: stainless steel rather than carbon, which increases weight by around 40g to 220g.

I've had no comfort issues whatsoever with the Giant TCR Advanced Pro 1 Disc, finding it easy to stay seated for long periods and not getting rattled on fast, sketchy descents. If you ever did feel the need from more cosseting, you could easily switch to 28mm tyres (or even wider) and run lower pressures.

Of the recent bikes we've reviewed on road.cc, one of the closest for price is Merida'a Scultura Endurance 7000-E at £3,500. Like the Giant, the Merida is equipped with a Shimano Ultegra groupset, but it's the considerably more expensive Di2 version (with electronic rather than mechanical shifting). On the flip side, the Giant has a power meter and better wheels, so it comes down to what you value most.

Trek's new Emonda SL 6 Pro (£3,350) is another interesting rival, coming with a Shimano Ultegra (mechanical) groupset and Bontrager's very good Aeolus Elite 35 wheels. Trek does spec power meters on some models in the range, but not on this one, so that might be an important factor for you.

Conclusion

The Giant TCR Advanced Pro 1 Disc is an excellent road bike that performs with aplomb and a bit of a flourish. It's zippy and efficient while offering well-balanced handling. Add in a high quality build, excellent wheels and a power meter, and you have a seriously strong contender.

Verdict

Exceptional all-round performance and well worth the money