Giant Defy Advanced 1 2023

Look up 'modern endurance bike' in the Big 21st Century Bicycle Encyclopedia and you'd likely find a picture of a Giant Defy Advanced 1. It's a steady, ride-all-day bike with dependable handling, perfect for long days out and versatile enough to tackle easier dirt roads and trails.

> Buy now: Giant Defy Advanced 1 for £2,599 from Dever Cycles 

Our best endurance road bikes buyer's guide and best road bikes buyer's guide cover our top tarmac-friendly bike choices.

The 2024 version of the Defy has actually just launched – which you can read about here – so that means there are some good discounts on this one, if you aren’t fussy about having the latest model. As we discovered, it’s still an excellent bike.

Ride & handling

If you're looking for a bike that can tackle just about anything British roads will throw at you, the Giant Defy Advanced 1 perfectly fits the bill, with steady handling at all speeds, wide gear range, excellent brakes, and the precision and tunability of the latest-generation Shimano Di2 electronic shifting.

It's the definitive modern sportive and endurance bike.

What makes the Defy Advanced 1 so good is its carefully balanced handling. It's composed and friendly whether you're tapping out a rhythm uphill at $SmallNumber miles per hour, or hooning down in a deep tuck with one eye on the road and the other on your speedo.

Its reassuring ride feel just encourages that kind of silly behaviour.

It's unflappable on bad roads thanks in part to its Giant Gavia Fondo 1 Tubeless tyres – nominally 32mm wide, they're actually 34mm so there's plenty of rubber on the road.

It handles dirt roads with aplomb, as you'd expect from those fat tyres, a size you only found on gravel bikes not very long ago.

Also keeping things steady is the combination of a 72.5° head angle and 50mm fork offset that yields 58mm of trail.

That's not so high it makes the handling too stable though. The Defy doesn't dive into corners like a crit bike, but still turns willingly and holds a line through a turn without fuss.

Frame

At the Defy Advanced 1's heart is a frame moulded from Giant's own High Performance Grade carbon fibre (top-end Giant frames, designated SL, use what Giant calls Professional Grade carbon).

Notable features include internal routing for the brake hoses and the wired portion of the Di2 system; a press-fit bottom bracket; mudguard mounts (with a dinky bolt-on seatstay bridge supplied); and clearance for a claimed maximum tyre width of 35mm.

You might squeeze in tyres a little bigger than that but I found that a 40mm tyre rubs the fork crown.

Our size ML test bike has a reach of 381mm and stack of 586mm. That's 12mm shorter and 24mm taller than Giant's TCR race bikes, which yields a more upright, cruisy riding position out of the box. Since I like a stretched position, I swapped out the stock 100mm stem for a 120mm.

Components

The new 105 Di2 shifting works flawlessly with very fast, clinically efficient shifts up and down the gears. Stu covered it in detail when it was launched so for all the details, go read that article.

I disagree with Stu on a couple of minor points. I don't see a pressing need for closer-ratio cassettes than the 11-34 and 11-36 on offer. You can always fit an Ultegra 11-30 if large sprockets really upset you, and I frequently found myself double-shifting when I was in the middle sprockets to get a sufficiently higher or lower gear. The world just doesn't very often present changes in gradient that let you shift smoothly one sprocket at a time.

Giant has fitted the 11-34 cassette but will use 11-36 next year to reduce the low gear a touch. Shimano listed the 11-36 option when 105 Di2 was launched but it wasn't actually available in time for the Defy to use it.

For a low-gear fan (or unfit fat git if you like) the 11-36 option is good to see. I'd really like Shimano to offer a 46/30 chainset at 105 level as well. I've been riding 46/30 with a 12-34 11-speed cassette and that gives a range that suits me perfectly. (The 12-34 is a regular 11-34 11-speed with a 12-tooth top sprocket instead of the 11 so you don't get a huge jump between the top two gears.)

The 12-speed 11-34 would duplicate that set-up but with an extra top gear for downhill zoomies, while the 11-36 provides a useful slightly lower bottom gear.

A criticism we've long levelled at Di2 is that it's hard to tell the buttons apart when you're wearing winter gloves. I found that was still a slight problem, along with retraining my reflexes to hit the right buttons.

Shimano's hydraulic disc brakes are universally well-regarded. Add me to the fan club. They're precise, easily modulated and have gobs of stopping power. Just don't get too enthusiastic and put yourself over the handlebar.

Like other Defy, Contend and Revolt models, the Defy Advanced 1 has Giant's D-Fuse seatpost with a D-shaped composite shaft that's supposed to provide a bit of comfort-enhancing flex. However, it seems to work better the more seatpost you have showing, and at my saddle height it just doesn't feel like it's moving much at all. (On paper I should ride a size M Defy, but it would then be on the short side and require a silly handlebar stem to get my right position.)

Giant offers several models of D-Fuse post, but there isn't the range of options you'd have if this was just a regular 27.2mm round post. Since Canyon has demonstrated that you can make a round flexible post, Giant's D-shape could be seen as unnecessary standards-dodging.

The Giant Approach saddle is firm and flat with a pressure-relieving cutaway to cosset your perineum.

I prefer saddles with more of a dip; the Approach was okay, but I'd fit something that better fit my bum.

Some Giant bikes use a steerer that's 1 1/4in diameter at the top. The Defy's is the far more common 1 1/8in so you can fit an easy-to-find stem if you need to adjust the position to suit you. The Defy almost fits me off-the-peg, except for the 100mm stem; I swapped in a 120mm.

I didn't get on with the own-brand handlebar Giant has fitted here. I wanted a little more drop – and anyone with bigger hands than mine will probably find the hooks really cramped – and the flattened top section just ends up narrow and awkward.

For comparison Decathlon's Triban RC 520 also uses a bar with a flattened top section, but that bar has a much fatter cross-section (it looks like it's 31.8mm before shaping; Giant's is 23.8mm) so you end up with a broad, comfortable, fist-filler of a top section.

Slightly disappointing to see that Giant has used the non-series FC-RS520 chainset instead of the 105 unit. The 105 chainset is lighter, by dint of being hollow, and in my opinion better looking, while the FC-RS520 appears to be a Tiagra chainset tweaked to work with 12-speed chainrings.

Too Tyred

In the 40 years I've been riding bikes I've watched road bike tyre sizes shrink and then swell. Back in the 1980s it was all touring bikes and 1 1/4in (32mm) or even 1 3/8in (35mm) tyres – the latter great for 'comfy commuting' as a riding buddy of mine put it. Then tyres got skinny, and measured in millimetres. They also got physically thinner than the markings on the sidewalls claimed as tyre makers vied to make the lightest 25mm and 23mm rubber; the easiest way to do that was to make them 24mm, 22mm and even smaller.

Eventually sanity prevailed and accurate markings returned to tyres. Then a bunch of factors came together to make tyres fatter: disc brakes freed bike designers from the constraints of wrapping a brake round the tyre; the development of gravel bikes made fat tyres on road bikes trendy; riders began to look for less-trafficked roads, which often meant very minor rural byways with trashed surfaces; and 'Actually it's a bit more complicated than that' replaced the previous orthodoxy that skinny tyres were faster.

Ten years ago nobody would have put 32mm tyres on even an endurance road bike like the Defy Advanced 1 and they would definitely not have gone for rubber like these Giant Gavia Fondo 1 Tubeless tyres that are actually 34mm across according to my trusty vernier callipers. It took me a while to get the tyres dialled in. I eventually ended up with 50-60psi in them for road riding, making them floaty, grippy and comfortable.

Props to Giant for setting the tyres up tubeless out of the box too. Most manufacturers slap in tubes even if they've supplied tubeless-compatible tyres and wheels, but Giant says it has sufficient confidence in the tolerances of their tyres and rims that it can ship bikes with the tyres installed ready for the dealer to put in sealant.

Giant UK's Dave Ward told me in an email: 'It's all about tolerances. We make all of our own rims and Maxxis makes all of our own-brand tubeless tyres and they were the only company that could guarantee the tolerances needed to go all-in tubeless to the level that we have.

'We fit the tubeless rim tape, valve and the tyre at the factory then the dealer just adds the sealant. The tyres are easy to fit by hand and 99 times out of a hundred can be fitted with a track pump.

'We don't put the sealant in the tyres in the factory due to its shelf life when it's in the tyre. We supply 2x60ml bottles of sealant with the bikes and the sealant we use is Stan's in a Giant bottle.'

Going Fully Synchro

One of your options in setting up the Shimano 105 Di2 gearing is to have it shift chainrings for you, when you reach a certain point on the sprockets. I've been intrigued by this idea, dubbed Synchronized Shift, ever since Shimano first introduced it on the XTR mountain bike groupset in 2014, but aside from passing mentions, no other road.cc reviewer seems to have looked at it in depth.

With Synchro Shift you can set up the shifting so that you only have to select a lower or a higher gear. Using Shimano's E-Tube Project app you choose the point at which the system shifts chainrings and you configure any of the buttons on the levers to do whatever you want.

Out of the box, the buttons on the right shifter move the rear derailleur. The front button moves to larger sprockets and the rear to smaller ones.

If you switch to Synchro Shift without changing anything else, that still happens but at a certain point the system does a double shift, changing both front and rear derailleurs to take you to the next gear.

Say you start in the big ring and smallest sprocket and repeatedly press the front button to shift to bigger sprockets. When the derailleur reaches, say, the 24-tooth sprocket, the next shift changes the chainring from 50 to 34 and the sprocket to the 19-toother.

If you've connected a Garmin device to your Di2 gears you get a warning when you reach 50/24 that the next shift will involve the chainrings. You need that warning, because the combination of a chainring shift and a two-sprocket shift at the back takes about a second during which you have to back off pedalling effort a little.

You probably wouldn't want to set Di2 up like this if you were racing; that shift might be a bit startling in the heat of battle. But for cruisy riding, it's great because you simply don't have to think about gears, you just press a button for easier gears and another for harder gears. I'm a big fan of anything that reduces my need to think while riding bike so I can just get on with enjoying the ride!

Since the buttons on your left lever now have nothing to do, you can program them to change screens on your Garmin, for example.

Or you can make the interface even more radical. I set up both right-hand buttons to shift to larger sprockets and both left-hand to change to smaller. That almost replicates the way my first-generation SRAM Red eTap system works, but with a twist – it's the opposite way round from Red eTap. I've never quite got my head around the way that pushing a v1.0 eTap right hand switch moves the derailleur from right to left; it feels to me like it should be the other way and if I could afford current eTap that's how I'd set it up.

The Missing Manual

The Di2 shifting system desperately needs a single, unified user manual covering installation, set-up and all aspects of use. At the moment this information is scattered among several Shimano documents online, and partly but not completely covered in the built-in documentation for the E-Tube app.

One piece of information I really struggled to find in official sources was how to change shifting modes between Manual, fully Synchronized and Semi-Synchronized. Props to Terry at BetterShifting for his 12-Speed Di2 New User Guide, which explains that you need to double-press the function button on the rear derailleur to cycle between modes.

The situation's not helped by the E-Tube app being full of references to capabilities that 12-speed road Di2 simply doesn't have. Fully automatic shifting? No, 105 Di2 can't do that. You probably wouldn't want it to, but it's distracting to keep finding it when you're looking for something else, and since the app knows exactly which components you have, it'd be trivial to restrict it to only covering the available functions.

Oh, and by the way, the charging cable for Di2 costs £45, so you'll want to put it somewhere safe. Or attach an Apple AirTag to it. Or both.

I do think it's a pity that Shimano didn't manage to make 105 Di2 cheaper. £3,000-ish bikes came with Ultegra Di2 not very long ago. Yes, the world's gone insane and everything has rocketed in price in recent years, but hitting the same price as SRAM Rival would have been quite a statement and made the (hopefully temporary) lack of mechanical 12-speed 105 easier to take.

Rivals

Despite my carping about the cost of 105 Di2, above, the Defy Advanced 1 turns out to be one of the cheaper endurance bikes you can buy with electronic shifting.

Stu Tested the Boardman SLR 9.6 Disc, which does get you Shimano Ultegra, but it's £3,950.

For the same price as the Giant, the 2024 Orro Gold STC 105 Di2 looks like an excellent update of a bike we've always liked.

If you want something a bit more slanted to off-road fun, you can currently grab Orro's Terra C 105 Di2 for just £2,399 or you could stay Tarmac-bound with the Merida Scultura Endurance 6000 at £3,300 – Stu liked an earlier version. At £3,499 Scott's Addict 10 is also worth a look as Stu found when he rode it.

It seems fair to look at 'all-road' bikes as Defy rivals too, given the Defy's ability to take tyres 35mm wide and a shade fatter. For £3,500, the Vitus Venon EVO-GR Rival AXS is a racy graveller that really impressed us.

Conclusions

The quintessential modern endurance bike, the Giant Defy Advanced 1 does everything you could reasonably expect from a three-grand bike and does it all very, very well.

Who should buy the Giant Defy Advanced 1?

If you love long days on the bike and especially if you're not averse to a bit of dirt road shenanigans, the Defy Advanced 1 could well be your perfect bike (assuming it fits you, of course).

Verdict

Excellent do-almost-everything endurance bike; practically the type specimen for the genre