There are many new gravel bikes on the market that promises a great level of comfort. Among them is the GT Grade Carbon, which is said to offer ample comfort thanks to its floating seat stay design.
I tested the vibration levels of the GT Grade Carbon and then compared it to my benchmark bike to see just how comfortable it is.
Does it offer what it promises?
The GT Grade Carbon Expert
GT was among the pioneers of gravel-specific bikes, and the Grade is one of the best examples of what a gravel bike is all about.
The Grade’s unique flexing rear end combined with comfortable geometry makes it a very appealing package. From my perspective, the only thing holding the previous Grade from winning more awards was its limited tire clearance.
Fortunately, GT addressed that issue with the latest Grade – this time you can put in a 42mm tire (tested and confirmed). Add to this a new and improved flexing rear frame triangle and you, at least on paper – get the winning formula.
What’s So Special About This Bike?
The GT Grade’s trademark is its floating seat stay construction.
On the new GT Grade, we have the latest iteration of this approach – fiberglass seat stays covered with carbon skin that floats freely without any contact with the seat tube. Add to that the seat tube that’s flattened near the bottom bracket (allowing for even more flex) and you should get a very compliant rear frame triangle.
But GT’s innovative ideas did not stop there. They also made something interesting on the front of the bike.
The new GT Grade fork uses a special flip chip system that allows you to change the fork offset, and thus the bike’s handling. This means that when you are on a bikepacking adventure, you can make your steering more agile simply by increasing the standard 55mm offset up to 70mm.
One last thing that should be mentioned is the choice of the FSA Omega crankset. It has 46/30 tooth chainrings, which combined with a standard 11-34 tooth cassette offers a wide range of gears for both climbing and riding fast on the open road. During my testing, I never felt I needed higher or lower gear.
The rest of the bike is a rather standard package. Shimano 105 groupset. WTB ST i23 rims. WTB Riddler 700C x 37mm tires.
Do Floating Seat Stays Actually Work?
The floating seat stays were the thing that got me interested in the Grade in the first place, so I was very eager to see if they are a gimmick.
To my surprise, it took just a few hundred metres to realize that floating seat stays are definitely not a gimmick. This design is so effective at damping vibration that, on a fast gravel road, you do not need a fancy leaf-spring carbon seatpost or even a flexible saddle shell – the frame comfort is enough.
What’s more, my vibration readings showed only a very modest comfort improvement when I installed my Ergon Allroad Pro seatpost and Brooks C17 saddle (on the fast gravel road). These two products are known for their exceptional vibration-damping properties, so if they can’t achieve a big comfort improvement, the GT’s frame design must be something else.
The GT Grade Flip Chip Fork
A flip-chip fork is not a new idea for gravel bikes. Polish bike brand Rondo introduced a similar design a few years ago.
The main difference between Rondo and GT is that Rondo modifies the bike’s size by increasing the stack height and reducing the reach of the frame. On the other hand, GT is all about changing the steering characteristic of the bike.
Changing the flip-chip position has a perceptible effect on the bike’s handling. You can make the bike feel more stable or more agile.
But to be honest, we as human beings have a remarkable ability to adjust to changes very quickly – after five or ten minutes, you’ll likely find the handling difference disappear.
How Does The GT Grade Carbon Ride?
This bike feels fast! The stiff bottom bracket and thick downtube create a bike that feels like it can effectively transfer your pedal power into rapid forward movement.
This is especially noticeable when accelerating from a standstill – the difference between the GT Grade and my Jamis Renegade feels huge in this test. But when you are traveling at a steady speed like 30 km/h, the difference is not noticeable.
The biggest distinction between these two bikes comes from the ‘long reach’ geometry of the GT Grade. The GT makes me feel a little bit too stretched for my liking (reducing the stem length got me part of the way there).
How Comfortable Is The Bike To Ride?
The front end of the bike actually rides rather stiffly. But adding a Redshift ShockStop stem during the test helped a lot. And when I added a 42mm Soma Cazadero tire it improved the front-end comfort even more.
As for the rear end, the GT Grade Carbon is a hugely comfortable bike and I honestly think that you will have a very hard time finding something more comfortable (maybe the Cannondale Topstone, BMC URS, or Moots Routt YBB).
Unfortunately, I did not have the possibility to test a GT Grade with a Lauf Grit fork. But my feeling is that when equipped with a suspension fork like this, the GT Grade bike could easily be one of the most comfortable gravel bike money can buy. That’s even on its 37mm WTB Riddler tires, which were surprisingly good in terms of reducing vibrations (for their width).
Vibration Test Results
I am comparing the GT Grade Carbon to my Jamis Renegade Steel benchmark bike equipped with Soma Cazadero 700x42mm tires (30spi), a Redshift ShockStop stem, an Ergon Allroad Pro seatpost, and a Brooks C17 saddle.
You can see my vibration measurement procedure & outdoor test courses HERE.
Above you will find the front and rear comfort difference between the completely stock GT Grade Carbon compared to my benchmark bike.
While the GT Grade was miles behind when it came to front-end comfort, it was actually better than the rear of my benchmark bike on the fast gravel road. This is despite it having an inferior seatpost and saddle, speaking volumes about those floating seat stays.
But, as you may already know, I am after the most comfortable bike possible, so I fitted the GT Grade with all of the comfort components from my benchmark bike – that’s the stem, seatpost, saddle, and tires.
I’m calling this bike the “GT Grade Carbon Max”.
As you can see, the GT Grade Carbon Max was very close to my benchmark bike in terms of comfort. The GT’s fork and handlebar are perhaps a little less compliant, resulting in less vibration damping than my Jamis Renegade.
But on the fast gravel road, the rear-end comfort of the bike was even better than my benchmark bike. This is a true testament to the comfort of this frame.
Would I Buy The GT Grade Carbon?
Maybe, but I like steel for its springy ride feel.
Moreover, I am not after the stiffest and fastest-feeling frame possible. For my riding, a bike like my Jamis Renegade equipped with a Redshift ShockStop suspension stem, and Ergon Allroad Pro carbon seatpost is a great comfort choice.
But if you are looking for something similarly comfortable, but lighter and faster, then you will be very happy riding the GT Grade Carbon. Just put a Redshift ShockStop stem on it, and you will be ready for any gravel road ahead.
