BIKE TEST: GIANT FULL-E+ 0 SX
First U.S. electric mountain bike for Giant
Doug Barnett tests the IP56 rating in a rare stream caused by all the rain in Southern California. The bike plowed through everything we rode it on without hesitation.
Giant has had electric mountain bikes in Europe for quite a few years. Europe has embraced electric bikes fully, and in places like Germany, one in three mountain bikes sold now is electric.
Giant’s Full-E line of mountain bikes has been available in Europe for a while, but it is just now available in the U.S. We actually were loaned one of the very first ones that arrived at Giant’s U.S. offices. We picked it up and took it on its maiden ride with a group of riders from Giant to get a first impression, and since then, the more we ride it, the more we like it.
THE BIKE
The Full-E+ 0 SX is the current U.S. flagship bike. The “0” designation means it’s the top of the line. Their nomenclature is akin to a golf score. The lower the number, the better the bike. The Full-E+ 1 is over $2000 less expensive, at $5299, with lesser (but still good) components like a Shimano drivetrain and Fox Float shock versus the 0 level’s SRAM EX1, RockShox Lyric fork and SuperDeluxe RCT3 rear shock.

Giant controls every aspect of bicycle building, including smelting their own specific aluminum at their own plant in Taiwan. It’s branded ALUXX. Their Maestro suspension platform for the bike includes a top linkage made of carbon fiber, a piece that they could have made of another material, but they chose carbon to stiffen the rear end and shave some weight. That one piece is incredibly hard to make out of carbon fiber because of the intricate shape. Other little details, like the chainguide in front, are also made from carbon fiber.

The motor they’ve chosen is the Yamaha PW, one of our favorites. Giant puts in their own custom tuning and brands the motor as their SyncDrive Sport. They’ve paired it with the SRAM EX1 cassette and derailleur, and a custom-forged Praxis 38T front sprocket. Why not use the SRAM EX1 version? Because that version is made from aluminum, and Giant found that they wore out too quickly. They employed Praxis Works to make the steel gear for much longer wear and durability.

For 2017 Yamaha and Bosch have increased their batteries from 400 to 500 watt-hours. Giant semi-integrates theirs into the frame, and it’s a different form factor than a stock Yamaha battery.

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The handlebars are Giant’s own Contact DH, which are great for control, but apparently can cause trouble in Australia. Down Under, due to a 1979 law, bicycles used on public thoroughfares cannot be wider than 700mm. Giant had to recall 28,000 bikes sold in Australia because they hadn’t included a sticker that says the bikes can only be used for “off-road, competition use only.” If you buy one here in the U.S., it will still come with one of those stickers.
THE RIDE
The SyncDrive motor has some definite performance tweaks. Most Yamaha motors we ride cut the power when cadence goes above 89–90 rpm, but we saw 95+ before this motor cut, making it a much more natural machine for experienced mountain bikers who prefer spinning over mashing.
There’s plenty of torque at 80 N/m, and typical of most Yamaha configurations, it starts in at nearly 0 rpm. It’s a really easy bike to climb hills on, even when you get stuck behind a slower rider on a non-motorized bike. Low cadence is no sweat, literally.
Giant has definitely found the sweet spot for steering. Turning is sharp and crisp enough while still having a slack0enough angle to stay safe on fast descents. Chainstays are long enough at 46.3cm (in all frame sizes) to keep you confident on steep climbs, but not so long it feels like a container ship while cornering.

Giant has put years of experience to work on the suspension too. We learned to just trust it to carry us over sections we’d normally hold way back on. The head tube angle and forks are great for general trails and in combination with the slightly plus-sized tires; it keeps you out of trouble on rutted trails. The 140mm of travel (160 in the front) is great for bombing down rocky or rutted trails with roots, and the solid Nobby Nic tread bites well to make the bike feel planted anywhere. Those tires are tubeless ready, should you decide to go that way.
There are three levels of power: Eco, Normal and Power. Many riders liked just using Eco and selecting the power level on a controller that is bulletproof (possibly the only metal one we’ve ever seen); it was very easy to find with your thumb, even while wearing gloves.
All that power, mixed with the SRAM e-bike-specific eight-speed cassette and derailleur, made for a perfect combination. When much of mountain biking is going to 1×11, this 1×8 setup is fantastic.
“It’s a really easy bike to climb hills on, even when you get stuck behind a slower rider on a non-motorized bike.”
The drivetrain is sturdy enough to handle the intense power of rider plus motor and cover such a wide range of gearing. It clunks into each gear. There’s a big step between them, but you don’t feel that much of a difference on your legs at each shift. We never ran out of gears while climbing, and only on steep descents did we not have enough gears to avoid spinning out. That’s okay, we’ll just coast!
If you do find yourself on a steep-enough hill to need to walk up, there’s a walk-assist function to let the bike power itself up the hill a little so you’re not pushing a 50-plus-pound bike and yourself up the climb.

Controlling that power is SRAM Guide RSC disc brakes with 200mm rotors front and rear. They’re a perfect choice for this bike; the level of modulation and control is incredible and confidence-inspiring.
The dropper seatpost, a Giant Contact SL Switch Trail, was a mandatory and welcome control. The Giant Contact SL saddle is comfortable enough on short rides, but after a couple of hours, it starts feeling like it’s made of wood. Your mileage may vary, because a properly fitted saddle makes all the difference. This one wasn’t our personal fit.
Giant has been working on an app to allow customers the option of custom-tuning the system to some degree. That would be interesting to see the effect on performance, if it makes it into this current bike.
THE VERDICT
This is Giant’s current flagship full-suspension mountain bike—the best of the best. It’s an overall great performer for any type of riding and for very experienced riders with a generous budget and a top-of-the-line need. It’s not a downhiller, but it should be at home on any XC, or even enduro, rides. The bike’s battery life is as good as other bikes we’ve ridden with Yamaha motors, even with the performance tuning Giant has done. The performance of this bike is almost pro-level, certainly more than capable for most riders we know, but it’s better to have something above your level. Overall, we enjoyed the ride.
SPECS
2017 GIANT FULL-E+ 0 SX
MSRP: $7699 Motor: Giant SyncDrive Sport, powered by Yamaha
Battery: Giant EnergyPak500, 36V, 13.8Ah
Charge time: 4.5 hours
Top speed: 20 mph (with assist)
Range: 25–40 miles (tested)
Drive: Praxis Works Custom Forged, 38T and SRAM EX-1 e-MTB-specific 11-48T, 8-speed
Brakes: SRAM Guide RSC, 200mm discs
Controls: Giant PedalPlus 4-sensor technology
Fork: RockShox Lyrik RCT3, 15mm thru-axle, overdrive, 150mm
Frame: ALUXX SL-grade aluminum
Tires: Schwalbe Nobby Nic 27.5×2.6
Weight: 51 lb.
Color choices: Black/bright red/blue
Sizes: S, M, L, XL
GIANT FULL E+ 0 SX PRO
It’s funny how things work out sometimes. Before Giant handed us a 2017 Full-E+ 0 SX to review, they invited us to Corsica, France, to preview the 2018 version. We were the only American magazine invited for the preview.
Truly the bike from the future, it will be available in Europe in early 2018, but won’t even make its way to the States until the middle of next year. It’s virtually the same bike as the 2017, but with one major change—the 2018 Full-E+ will be equipped with Giant’s new SyncDrive Pro, a renamed Yamaha PW-X motor with Giant’s own custom tuning on the software.
The new motor is actually available in Europe this year but not in the U.S., and it adds more power and torque to compete with the Bosch Performance CX. It’s also 13 percent smaller and 380 grams lighter this year.
They’ve not only made the motor smaller and lighter, but a new ISIS-spline axle mated with a clutch with tighter pawls allows a three-times-quicker mechanical response from rider input at the crank. Part of Giant’s performance tweaks make the electronic response three times quicker (to >190 milliseconds) as well.
The Q factor (distance between the outside of the crank arms) has been reduced to 168mm from 186 for a more stable stance on the pedals.
THE RIDE
On the trails it’s quite a machine. The bike is built for a wide audience, meaning that it can be used for enduro rides, cross-country, all-mountain—a little of everything.
Our first ride was an enduro-style ride through the rocky, muddy, cow-poop-riddled Corsican mountains. It was breathtaking and brisk, with the starting temperatures at just above freezing. We set the sag on the suspension at 30 percent, and that seemed pretty good on this bike. The back end of the bike is reasonably long, which is really important on steep climbs with an electric bike, especially a powerful one. Shorter rear ends loop out easily.
The front end feels a bit short, and though the 66.5-degree head angle is great for being able to throw the bike around, on technical or fast descents, it doesn’t inspire all the confidence in the world. We had a few instances of feeling like we might easily go over the bars on some downhill sections with large rocks.
One of the things we love about Yamaha motors is the power and torque from the start of the pedal stroke. Giant has tuned the motor to always provide this torque instantly when you start pedaling. They’ve also tweaked the top end on every power level to allow for up to 120 rpm, a vast improvement over the previous motor that cuts out at about 90 rpm.
Their performance tuning on the motor is impressive, all 80 N/m of torque at all levels—from just over 0 rpm all the way up to 120. This is the first bike we’ve ever ridden that can break the back tire loose from a dead start on a steep hill.
Giant worked with Yamaha to make their own PW-X system have five levels—Eco, Tour, Active, Sport and Power. Power provides 360 percent assist via a torque sensor, so if you put in 100 watts of power, overall output of you plus the motor equals 460 watts. It comes with a new display that’s small, blends in with the bike, and is bright and easy to read. You can also adjust the brightness to your own preference.
The bike comes spec’d with Maxxis Rekon tires that are 2.6 inches in diameter. This is on the cusp of being a plus-sized tire and sits in a true sweet spot. It’s narrow enough to knife through about anything, but with a little lower pressure, it rolls right over sand with a stability that you only get from larger tires. Our bikes came with a possibly better tire, the Maxxis Minion DHF. The massive knobs on these tires grab everything. We’re not sure if the Rekons are a better choice, as we loved the Minions on just about every surface.
The Yamaha PW system we’re used to has substantial range, and that’s with the 400-watt-hour batteries. The new batteries are 500 watt-hours, even on the current PW system, theoretically offering 25 percent more range. But, on our first ride, we wouldn’t have made it the full 25 kilometers (15 miles) on rugged terrain. Granted, we weren’t riding in Eco, but we don’t normally anyway. For steep hills we used Power and Sport just to get a feel for how much they can apparently flatten a hill. Downhill we were usually on Eco. We spent a fair amount of time in Active and a tiny bit in Tour as well. We wonder if the performance tweaks Giant has applied affect this, but it is notable.
Giant has been working on an app to allow customers the option of custom-tuning the system to some degree. That would be interesting to see the effect on performance.
SPECS
2018 GIANT FULL-E+ 0 SX PRO
MSRP: $7700
Motor: Yamaha PW-X, custom tuned
Battery: Yamaha, 500Wh
Charge time: 4.5 hours
Top speed: 20 mph (with assist)
Range: 20–30 miles (tested)
Drive: SRAM EX-1 e-MTB-specific 11-48T, 8-speed
Brakes: SRAM Guide RSC, 200mm discs
Controls: Yamaha
Fork: RockShox Lyrik RCT3, 15mm thru-axle, overdrive, 150mm
Frame: ALUXX SL-grade aluminum
Weight: 51 lb
Color choices: Gray