It’s fairly enjoyable to be a gear tester within the age of gravel’s fast delivery and astronomical rise. Everybody’s received an opinion about what gravel is and what it must be. Maybe Shimano has an outsized say in that narrative. With the launch of the GRX drivetrain, Shimano despatched a loud message to the bike world: Gravel bikes deserve their very own drivetrain. No extra retrofitting.
An organization makes such claims when it acknowledges a sure sort of using isn’t going away. So drop-bar using on dust? Right here to remain. (Yep, you possibly can argue it by no means went away. I lived by way of the 90s and early 2000s too!)
Which means the GRX drivetrain deserves evaluation on its meant use, reasonably than towards drivetrains retrofitted from the MTB or highway world. And that’s what I’ve executed over the course of the final 12 months.
See it in motion in my video evaluate above, however hold studying for closeup images and some further particulars not included within the video.
The GRX drivetrain seems loads like another drivetrain, which shouldn’t come as an excessive amount of of a shock. Gravel seems an terrible lot like different sorts of using, no less than at first look. However as is the case with gravel using itself, the subtleties of the GRX drivetrain are what set it aside.
The controls exemplify the notion of subtlety properly. Outwardly, the form is way the identical as Shimano’s different STI Di2 controls. However on additional inspection, notable particulars stand out. The texturing on the brake hoods, for instance, is supposed that can assist you keep a optimistic grip on tough terrain. The brake levers themselves have a flatter, wider form so you possibly can as soon as once more get a optimistic grip when the terrain will get chattery.
And people brake levers additionally cheat extra inward towards the bars. That reduces the space your fingers must stretch to have interaction the levers. It additionally means you get higher leverage, and therefore extra braking management if you want it.
The hoods too have a unique form. However Shimano additionally properly contains shift buttons right here, as they do on highway groupsets. The form of the hood encourages your hand to ‘slot’ into place. It’s a cushty cradle and permits a agency grip over tough terrain.
When you’re the sort to spend so much of time on the bar flats, Shimano’s received you coated with specially-designed inline brake levers. These non-compulsory levers are small and provide one other braking choice when your fingers are away from the hoods.
The rear derailleur encompasses a clutch system. This basically provides stress to the derailleur cage, thereby growing the strain on the chain. This helps scale back dropped chains, which is a must have if you’re using off-road.
1×11 or 2×11
Since GRX sticks with an 11 velocity drivetrain, there are many gearing choices accessible in each 1X and 2X setups. Technically, there aren’t any “GRX particular” cassettes, so you possibly can select from 11 velocity Shimano Street or MTB cassettes. How huge you possibly can go is determined by the rear derailleur. The RD-RX810 will match as much as a 34t max low sprocket and is supposed for 2x drivetrains with highway cassettes, whereas the RD-RX812 will match as much as a 42t low sprocket, and is supposed for 1x drivetrains.
I selected a 1X setup with a 40T chainring and an 11-40 cassette.
Because the cassettes are current 11-speed MTB or Street cassettes, in addition they use the prevailing HG freehub spline which means you most likely received’t have to purchase a brand new freehub to run the group. Which is good.
Di2 wiring stays the identical as different Shimano digital groupsets, so no surprises right here.
What makes GRX cool?
The standout options of GRX Di2 are pretty refined. The texturing on the brake hoods is a good instance of a transparent benefit to a devoted off-road groupset. The lever form and hood form additional complement this, and also you’ll discover a rise in hand stability and the convenience with which you’re capable of keep grip on the bars.
GRX is flexible, too. It’s simply as at dwelling on a cyclocross bike as it’s on a gravel bike. I rode a good bit of pavement with it too. My solely grievance there’s that it was simple to spin out, but when I used to be going to spend extra time on pavement, I may make adjustments to my gearing selections.
And naturally, Shimano’s legendarily clean shifting and robust braking make GRX a transparent winner off-road. I even bashed the rear derailleur a good few occasions, and it nonetheless shifts like a dream.
What are the drawbacks?
Regardless of all of the superior stuff, GRX Di2 does have a disadvantage or two. The primary and most important is similar disadvantage of each Di2 drivetrain: The wiring.
Whereas the wires assist make for crisp shifts, they’re additionally a ache to route by way of your body. And there are many them, with junction bins interspersed all through. So preliminary setup takes a while and endurance. As soon as it’s executed, you possible received’t suppose an excessive amount of about it, and I don’t — besides after I look down at my head tube and see a wire dangling there. However for those who’re not organising the drivetrain your self, you possible received’t suppose a lot concerning the wires in any respect.
The opposite disadvantage isn’t actually a disadvantage. The brake levers on the flats are cool, however I can’t determine why I would want them. They really feel nice and provide a lot of braking energy, however after utilizing GRX Di2 for nearly a 12 months, I can depend on my left hand what number of occasions I’ve used these levers on the dust and nonetheless have loads of fingers left over. You might discover a helpful state of affairs for them, however I by no means did.
After all, now that they’re put in, it’s fairly concerned to take them off. So they continue to be on my cockpit, regardless that I by no means use them.
GRX on the dust
I’ve spent nearly the whole lot of my gravel rides within the final 12 months on GRX Di2. There’s loads of it to discover right here in Colorado, and fortuitously, I’m spoiled with all kinds of gravel circumstances. From flat, semi-groomed dust roads to chunkier singletrack I most likely shouldn’t have ridden on a gravel bike, we’ve received all of it right here. (Nicely, apart from tremendous muddy circumstances. East coasters, be at liberty to chime in along with your take within the muck.)
It’s secure to say that for those who’ve ridden another Di2 system from Shimano, you’ll know precisely what to anticipate from GRX Di2. It shifts simply as easily and shortly as its siblings, and battery life appears to go on and on. Shimano continues to be the king of the citadel with regards to the shifting expertise and battery life.
I want to see a single-button model of the shifters, although. In different phrases, an analogous system to SRAM’s eTap paddles could be advantageous right here. That’s largely as a result of it’s simpler to hit one paddle reasonably than choose between two smaller ones, particularly off-road and if you’re carrying full-finger gloves.
It’s not laborious to shift GRX Di2 with the variety of buttons at the moment supplied, but it surely may very well be easier. Plus, with a 1X setup, quite a lot of the buttons turn out to be extraneous anyway.
Do we’d like devoted gravel drivetrains?
Don’t ever let anybody let you know that it’s essential run out to purchase a gravel drivetrain. It’s not a necessity with regards to gravel bikes. But it surely certain is good to have it.
You’ll be able to completely make a highway drivetrain, or a highway/MTB hybrid drivetrain, work simply superb to your gravel wants. However there are two compelling causes to put money into a gravel drivetrain.
First, for those who’re going to purchase a gravel bike sooner or later, it’s possible that bike will include a gravel-specific drivetrain anyway. So that you’re opting in whether or not you prefer it or not.
Second, devoted gravel drivetrains like GRX Di2 might carry out the identical capabilities as a highway or hybrid highway/MTB drivetrain, but it surely does so with extra particulars honed particularly to gravel. In different phrases, you’ll most likely have a greater expertise with a devoted gravel drivetrain in your gravel bike.
As a bonus, GRX Di2 works splendidly as a cyclocross drivetrain, too. So if you would like a single drivetrain to do all of it, GRX is actually a workhorse in that regard.
The ultimate phrase on GRX
I’ve very a lot loved the final 12 months of using with GRX Di2. It does all the pieces I would like it to do, reliably each time. And I recognize the subtleties that Shimano has packed into the general group that make it dirt-worthy. I’m particularly a fan of the textured brake hoods and the form of the brake levers themselves.
That stated, I wouldn’t name GRX Di2, or another gravel-specific drivetrain, actually essential. You’ll be able to completely get away with utilizing a highway drivetrain, or a Frankenstein setup that mixes a highway and mountain bike setup. However for those who’re after one thing extra streamlined for gravel, one thing that was made particularly for this rising section, it’s laborious to beat GRX Di2. If you wish to simplify your setup, go for the mechanical drivetrain as a substitute. But when the smoothest shifting attainable is excessive in your record, GRX Di2 takes the cake.