GT has launched the third-generation Grade Carbon, with a new suspension-equipped X model that shows the most significant shift in the brand’s gravel bike design since debuting in 2014.
The new frame retains GT’s unique approach, with its floating triple triangle that blends high-modulus (and high-stiffness) carbon fibre for the head tube, bottom bracket and chainstays, with low-modulus (and comfort-enhancing) fibres for the seatstays, and mid-modulus everywhere else.
These combine with the leaf-spring like seat tube to create a claimed 30mm of travel, without resorting to pivots or suspensions like Cannondale’s Topstone or Specialized’s Diverge STR.
What has changed, however, is GT’s approach to gravel geometry. The original GT Grade, launched in 2014, was more akin to a classic endurance road bike. The Mk 2 Grade, from 2020, introduced bigger tyre clearances (42c) and a flip-chip front fork to alter the trail, making the Grade versatile as an all-road endurance bike or a full-out gravel bike.
The third-generation bike, however, sees a shift to geometry that’s more focused on technical off-road riding, while also offering compatibility with the latest gravel suspension forks.
On the same theme, tyre clearance has increased to 50c without mudguards and 45c with. The Grade Carbon still comes with a removable mudguard/fender bridge. The new Grade Carbon has moved to a threaded bottom bracket, too.
There are two models of the Grade Carbon at launch, including the Grade Carbon X, equipped with a suspension fork and dropper post, while GT has updated the aluminium frame, too.
Frame geometry updated
GT has adapted the Grade Carbon’s geometry with an eye on off-road handling, primarily pushing the head tube angle out and increasing the length of the top tube.
The head tube angle has been relaxed to 70 degrees (from 72.3 degrees), but it retains the sporty 73-degree seat angle.
GT says the change in head tube angle pushes it out to the point where it helps with control in fast, rough and technical gravel riding. However, it doesn’t make the steering sloppy when climbing.
The head tube length has also been reduced to 162mm from 187mm (size large). This is to allow for suspension fork compatibility – something the Mk 2 Grade didn’t offer, because it had a parallel 1-1/8in steerer. All current gravel suspension forks have a tapered steerer.
The bottom bracket drop has increased to 75mm from 70mm, to take into account larger tyre sizes, and the reach is stretched out to 425mm from 400mm. The stack has dropped 9mm to 603mm.
GT claims this move to a longer front-centre will help riders centre their weight distribution more evenly, improving control off-road and also enabling riders to tune the bike more to their personal preference with handlebar setups (which vary significantly in the gravel world).
The seat tube has also dropped in length because GT envisages plenty of riders opting to use a gravel dropper post on the Grade, and this allows for maximum clearance and drop.
| S | M | L | XL | |
|---|---|---|---|---|
| Wheel size | 700c | 700c | 700c | 700c |
| Seat tube length (mm) | 450 | 500 | 550 | 600 |
| Top tube, horizontal (mm) | 553 | 581 | 609 | 683 |
| Top tube, actual (mm) | 530 | 560 | 591 | 623 |
| Head tube angle (degrees) | 70 | 70 | 70 | 70 |
| Seat tube angle, effective (degrees) | 73 | 73 | 73 | 73 |
| Standover height (mm) | 730 | 753 | 792 | 816 |
| Head tube length (mm) | 106 | 134 | 162 | 191 |
| Wheelbase (mm) | 1,040 | 1,069 | 1,099 | 1,129 |
| Front centre (mm) | 621 | 650 | 680 | 710 |
| Chainstay length (mm) | 430 | 430 | 430 | 430 |
| Bottom bracket drop (mm) | 75 | 75 | 75 | 75 |
| Bottom bracket height (mm) | 284 | 284 | 284 | 284 |
| Fork rake (degrees) | 55 | 55 | 55 | 55 |
| Trail (mm) | 72 | 72 | 72 | 72 |
| Stack (mm) | 550 | 577 | 603 | 630 |
| Reach (mm) | 385 | 405 | 425 | 445 |
Goodbye Press-fit, hello BSA
Elsewhere, GT has shifted away from a press-fit bottom bracket in favour of a BSA threaded bottom bracket.
Sitting forward of the BB is a new integrated frame protector on the underside of the down tube, to protect the carbon frame from rock strikes and reinforcing GT’s more gnarly focus for the new Grade.
50c tyre clearance
Gravel bike tyres – both in their construction and sizing – have moved on since 2020 too, and to reflect that the new Grade’s tyre clearance has been upped to 45c with fenders/mudguards or a huge 50c without.
With suspension compatibility and big tyre clearance, GT sees its rivals for the new Grade being bikes such as YT’s radical Szepter, Norco’s Search, BMC’s URS and Cannondale’s Topstone.
GT Grade Carbon range
GT is launching the range with the new Grade Carbon X (£3,000 / $4,000) as the hero model.
This comes complete with a RockShox Rudy XPLR 40mm-travel fork, a TransX dropper post with 50mm of drop and SRAM’s new Apex 1 groupset. The drivetrain combines a 40-tooth chainring with an 11-42t cassette. The left-hand shift lever, redundant in a 1x configuration, operates the dropper post.
We’ll have our Carbon X test bike arriving within the next week and we’ll report back as soon as we can take it out into the rough stuff.
A second model, the Carbon Expert (£2,200/$2,500), completes the initial carbon fibre range, with a 1x Shimano GRX groupset.
GT expects the Grade Carbon range to expand later this year.
GT will also offer an aluminium version with geometry based on the Carbon model, with four bikes starting from £1100/$1300 and rising to £1,550/$1,300.
GT Grade Carbon X
- Frame: GT Grade Carbon
- Groupset: SRAM Apex (40t, 11-42t)
- Wheels: WTB ST Light i23 TCS 2.0
- Tyres: WTB Resolute TCS Light, 700x42c
- Fork: Rockshox Rudy XPLR
- Dropper post: TranzX
- Price: £3,000/$4,000
GT Grade Carbon Elite
- Frame: GT Grade Carbon
- Groupset: Shimano GRX 400 (46/30t, 11-34t)
- Wheels: WTB ST i23 TCS 2.0
- Tyres: WTB Vulpine TCS Light, 700x40c
- Price: £2,200/$2,500
