The 2019 Giant Defy offers improved comfort, novel integration and an in-house power meter

The world's biggest bike brand updates its most popular road bike

Giant’s Defy endurance machine gains Propel-like integration to the cockpit, increased comfort, plus mounts for guards, and even a power meter on range-topping bikes.

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The Defy is a performance machine, yes it’s aimed at the endurance sector but it’s still designed with the same goals as Giant’s pro-race TCR or aero optimised Propel. So low weight, stiffness and all of the characteristics Giant applies to pro-level bikes are key.

The Defy is also Giant’s bread-and-butter machine; it’s globally its best-selling road bike, so it’s perhaps the most important bike in its range in terms of development.

Nixon Huang, the principal engineer on Defy, says: “Our main objective was to beat the performance of the 2015 bike, this was the first bike range to be disc only. We were ahead of the market on this along with specific compliance components like the D-Fuse post. We set out three goals for the updated Defy.”

The new Defy Advanced Pro 0
Sterllng Lorence

Giant’s three goals

1. Engineered compliance

Giant has set out to improve the ride quality it incorporated with the D-Fuse seatpost — that’s the D-shaped post designed to flex, and found on the last generation Defy and TCX ‘cross bikes.

The big development is taking the D-Fuse concept to a handlebar, which is a tougher call because you don’t want overly flexing bars that will be detrimental to handling, but you want to have enough to smooth the vibrations.

The new D-Fuse carbon bar is designed to offer bump-nulling flex
Sterllng Lorence

The new Contact SLR (carbon) and SL (aluminium) D-Fuse handlebars have a similar D-shaped profile — the carbon cross-section is 19mm x 35mm, and the alloy is 17mm x 30mm. The shape is orientated so it complies when being ‘pushed’ from above when you hit a rut or pothole, and Giant claims 10 percent more compliance than the standard Contact SLR bar.

The design also ensures that the handlebar stays stiff when you “pull”, when sprinting or climbing hard out of the saddle. Here it claims an increase in stiffness of a huge 30 percent.

Giant claims that the bar, working in conjunction with the seatpost, provides more than enough compliant comfort without having to resort to complex pivots, inserts or suspension.

With the frame’s reshaping and the new fork profile, Giant has also made provision for bigger tyres, with the new Defy able to easily take a 32c tyre.

Giant has increased the tyre clearance significantly over the previous generation, and added proper fender/mudguard mounts too
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2. Total control

Bit of an obvious one, but the new Defy features, as you’d expect, 12mm thru-axles (100 x 12 front, 142 x 12 rear) and of course flat mount disc mounts. I guess we don’t need to go over the advantages of discs brakes for control and consistent braking in all weathers.

3. Versatility

The versatility comes from the wider range of tyre sizes that are now possible to fit. Stick with some slender 25s for a smooth road sportive, or switch up to 32s if you’re heading out to ride pavé.

The geometry has been tweaked slightly, but the important head angle, seat angle, stack and reach remain the same as the previous generation. Only the wheelbase has been elongated, and only by 3mm to incorporate bigger tyres, along with the bottom bracket drop (up 5mm to 70mm), again to allow for larger rubber.

Tyre clearance at the rear is increased too
Sterllng Lorence

It’s not just fixtures and fittings that have been upgraded, Huang tells us that: “We’ve also looked at the composites makeup and revised the lay-up schedule (the way in which the carbon plies are orientated in the mold) to decrease weight and increase vital areas of stiffness at the head tube and BB shell.”

Nixon continues: “We’re able to make improvements and changes like this more efficiently than most as we own and completely control all of our manufacturing.”

In-house power meter