GT Grade endurance bike launched

Don't call it a gravel bike, GT says

First things first: GT doesn't want you to call the GT Grade a gravel racer, as the carbon framed disc road bike is more versatile than that.

Compared to a standard road race machine, the Grade's geometry leans far more towards an endurance or sportive bike; it's a little taller at the front, a little longer in its wheelbase (as you'd expect from a disc bike), a little lower at the bottom bracket and a little shorter in terms of top tube and reach. Rounding out the geometry to assist with rough-road riding, the head angle is slightly slackened.

GT arrived at what the company calls 'all-day' geometry using GURU's fit system data, as GT and GURU share the same parent company, CSG.

GT has been away from the higher end of road for a while now, but the brand historically had a deep road legacy. From 1996's US Olympic bikes which pioneered  clever aerodynamics, to the sponsorship of Lotto with Ti Edge bikes to later US teams JellyBelly and Saturn.

The GT Grade bike has been in development for three years. Initially the team at GT had identified a trend away from traditional race machines with the shift to a more comfortable ride and a more comfortable position. The bike is designed for adventure, GT says. It was designed to be able to be raced at a gran fondo, yet ridden off the beaten track on dirt or gravel roads aided by the inclusion of large volume tire and disc brakes.

The kicked-up chainstays and pencil-thin fibreglass seatstays are designed for comfort

Patrick Kay (PK), product manager for GT Road, said there is a disconnect between most everyday riders and pro bikes, "with prices hitting $10,000 that's not accressible, and more of a race bike than most of us will ever need."

"In the US and Canada, gravel and adventure road riding is a movement, not a trend," PK said. "Gran fondo riding in the US and UK is strong and growing. In Australia we are seeing riders taking advantage of the vast network of outback dirt roads, and even in Italy we are seeing events inspired by the [gravel road] Strada Bianca." GT is aiming the Grade at all of these riders.

The GT signature triple-triangle frame is here, but not just for looks, PK said. "By moving the seatstays outboard not only do we reduce the size of the rear triangle but also add plenty of tire clearance," PK said. "The bonus also off shifting the stays further outboard is the increase in torsional stiffness this enables."

GT's signature triple triangle allow for bigger tyres as well as a small rear triangle

The carbon frame weighs a claimed 965g for a 56cm. The butted alloy frame tips the scales at 1,320-1,350g. The top-of-the-range carbom fork is 475g with the thru-axle dropouts. On the alloy model GT uses a carbon fork with an alloy steerer, which is a little heavier.

The top three frames feature thru-axle dropouts, while the other four models use traditional dropouts and quick-release skewers.

Carbon and glass in the Grade frame

"We wanted to design this bike like you would a high-performance motorcycle," said Andy Schmitt, the engineer behind the Grade who has designed bikes for Schwinn, Mongoose, GT and Cannondale. "We created a solid foundation with the tapered head tube flowing into a large oversized down tube. This meets the PF30 oversized bottom bracket, which makes for a great terminal for the down tube and the oversized chanistays."

"The main frame's more compliant features are a seat tube and seat stays that are designed to flex," Schmitt said. "By kicking up the chainstays and having the seatstays fitting forward of the axle, that enables movement too. Finally, the top tube is allowed to flex upwards."

Shimano ICE rotors on the higher-end bikes

GT used very stiff high-modulus carbon in areas where ultimate stiffness is needed, but Schimitt wanted a completely different performance for the seatstays. GT experimented with the lowest modulus carbon they had for the long, arched stays, but wanted more flex, so the company ended up testing and experimenting with fibreglass. Fibreglass is has a similar strength to carbon but with a far lower modulus, and it is much cheaper. The fibreglass stays are finished with a final carbon layer to add impact resistance.

GT said the frame has created more than 10mm of deflection when measured at the top of the seatpost when you remove the seatpost flex from the equation.

The seat tube has a bi-directional taper at the bottom bracket; this flattening shape means the tube acts more like a hinge allowing for more fore-aft movement whilst the massive down tube and oversized chainstays and BB ensure drievetrain stiffness. The final component of the "flexi-comfort" design is the top tube; the flat, broad shape restricts the amount of lateral movement, whilst the shallow depth is designed to allow the top tube to arch upwards in the same path as the seatstays.

Details on the GT Grade

GT designed the carbon fork to complement the comfort inherent at the rear. By reducing the length of the taper, making more of the steerer a standard 11/8in diameter makes for more comfort, GT claims, but retaining the oversized lower race means the steering response isn't compromised. The 15m thru-axle design has a leading axle, so whilst the 15mm combats braking forces and adds steering precision the increased offset to 45mm aids smoothness, GT claims.

The top-three bikes feature thru-axle forks

The Grade is full of neat touches, like discreet mudguard eyes and a clip-on bridgeless fender mount with o-rings. The PF30 bottom bracket uses the new Praxis Works adaptor, which saves any fuss and faff associated with press-fit. Something that will set bike mechanics' minds at rest is the full external cable routing. Both drivetrain and hydraulic lines are grouped together with a neat routing system under the down tube.

Stan's NoTubes new Grail disc road rim, on DTSwiss 240 hubs, tips the scales at a claimed 1,685g a pair. The new Stan's Grail rim uses a 24mm outside diameter rim, with a large internal diameter of just over 20mm. They are of course tueless compatible, though the Grade ships with a standard clincher set-up. The Stan's rim is rated far higher (110psi) than the company's mountain bike rims.

The seven GT Grade models

Grade Ultegra carbon — £2,999 / US$3,299

  • Drivetrain: Shimano Ultegra 11-speed with BR-R685 hydraulics
  • Gear range: 52/36 and 11-32
  • Rims/hubs: Stan's NoTubes Grail rims (460g) on DTSwiss 240
  • Tyres: Continental Ultra Race 28c
  • Handlear: GT Drop-Tube bar (14-degree outward flair on the drops) 2014 butted aluminium
  • Seatpost: FSA K-Force light carbon
  • Saddle: FiZik Aliante MG

Grade 105 Carbon — £2,299 / US$2,599

  • Drivetrain: Shimano 105 with BR-R685
  • Gear range: 52/36 and 11-32
  • Rims/hubs: Stan's NoTubes Grail rims (460g) on Formula centre-lock hubs
  • Tyres: Continental Ultra Race 28c
  • Handlebar: GT Drop-Tube bar (14-degree outward flair on the drops), 6061 butted aluminium
  • Seatpost: FSA SLK carbon
  • Saddle: Fi'z;ik Aliante MG

Grade Alloy X — £1,599 / US$1,7499

  • Drivetrain: Shimano 105 with BR-R685
  • Gear range: 52/36 and 11-32
  • Rims/hubs: Stan's NoTubes Grail rims (460g) on Formula centre-lock hubs
  • Tyres: Continental Ultra Race 28c
  • Handlebar: GT Drop-Tube bar (14-degree outward flair on the drops) 6061 butted aluminium
  • Seatpost: FSA SLK carbon
  • Saddle: Fi'z;ik Aliante MG

Grade Alloy 105 — £1,099 / US$1,299

  • Drivetrain: Shimano 105 with TRP HYRD brakes
  • Gear range: 52/36 and 11-32
  • Tyres: Continental Ultra Race 28c
  • Handlebar: GT Drop-Tube bar (14-degree outward flair on the drops) 6061 butted aluminium

Grade Alloy Tiagra — £899 / US$1099

  • Drivetrain: Tiagra with TRP Spyre brakes
  • Gear range: 50/34 and 12-28
  • Tyres: Continental Ultra Race 28c
  • Handlebar: GT Drop-Tube bar (14-degree outward flair on the drops) 6061 butted aluminium

Grade Alloy Sora — £799 / US$899

  • Drivetrain: Shimano Sora 9 with Bangle mechanical brakes
  • Gear range: 50/34 and 12-28
  • Tyres: Continental UltraSport 28c
  • Handlebar: GT Drop-Tube bar (14-degree outward flair on the drops) 6061 butted aluminium

Grade Alloy Claris — £TBC / US$799

  • Drivetrain: Shimano Claris with Tektro mechanical brakes
  • Tyres: Continental UltraSport 28c
  • Handlebar: GT Drop-Tube bar (14-degree outward flair on the drops) 6061 butted aluminium

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