1×13 Shifting with Rotor on the Merlin Bikes Sandstone Gravel Bike

Hydraulic shifting? 13 speeds? What in tarnation?

That’s what was going through my head when I first saw Rotor’s 13-speed drivetrain kit at Sea Otter last year. The 1×13 kit is a follow up to Rotor’s Uno 2x groupset from four years ago. Like the Uno, the 1×13 uses hydraulically-actuated shifting for a groundbreaking industry first. As you might imagine, this tech is pricey, and probably not for everyone, myself included, but over the past few months, I’ve enjoyed riding it on this beautiful titanium chassis by none other than Merlin Bikes. Check out a full review of Rotor’s 1×13 and the Merlin Sandstone Gravel bike below.

It’s safe to assume that, consumers have fatigue in cycling tech. Incompatible groupsets, proprietary hub drivers, electronic shifting, flat-mount brakes. It’s inundating and I’m there with you! Believe it or not, 12 speed is good enough for me on a mountain bike and a 1×11 Force group has been just fine over the years. Yet, here we are! Please don’t let this paint a bleak picture of this review because I legitimately enjoyed riding this bike for the past few months, I just don’t want you to think I’m going to spend the next thousand words momma-birding you marketing jargon. This is truly from the heart.

Why Hydraulic? Why 13?

“Why not?” Would be my answer to both of those questions. Rotor has been around for a while yet they always seemed to be operating in the background. Their kits are made in Spain (apart from the road disc calipers, which are made by Magura) and have a very industrial look to them, when compared to the Xeno-inspired look of Shimano, Sram, and Campy. Where those brands bevel, Rotor expresses those edges and CNC marks. I’ve been a fan of their work for some time but was so hooked on 1x that the Uno 2x group just kinda floated past my radar.

Rotor wanted to do something that would merit them a bit of time in the limelight. While Shimano and SRAM are dedicated to improving their electronic shifting, Rotor wanted to look into hydraulic shifting methods due to their potentially low maintenance. They call this their sealed shift system. In theory, this should require less maintenance than cable-actuated shifting and not require charging of batteries. Hey, if hydro lines work for disc brakes, why not? I have a set of Force levers from 2015 that have never been bled. I’d love a shifting group that would deliver the same reliability.

Another reason Rotor went with the hydraulic system is it’s really difficult to enter into the drivetrain world with so many patents out there. Going with a new platform would allow them to research and develop a system that is microcosmic in design and functionality. Let’s call this hydraulic freedom.

As for the 13-speeds, Rotor’s intent is to offer up a wider gear range, with fewer big jumps, and a more streamlined kit.

Ride Experience

Honestly, I’m intimidated by this group. Nothing I write here will do it justice in terms of the hours spent developing this system…

Hopping onto a Rotor 1×13-equipped bike for the first time feels very familiar if you’re coming from SRAM, which most of my bikes are. The shifting design Rotor adopted is very similar to SRAM’s DoubleTap. That’s where hydraulic freedom comes into play! I thought for sure I would have issues with this kit but I tried to set my preconceptions aside. The first shift felt direct without giving you a big “klunnnnnk.” In fact, it felt smooth. I almost thought I hadn’t shifted but my cadence increased and I realized this was going to be a very unique product review.

The hoods are comfortable and wide, the shifting is smooth, the paddles have great ergonomics. It’s all looking up from here. Even getting used to Rotor’s oval chainring felt like an easy to manage transition. I really can’t believe something that looks so futuristic, so mechanical, so techy is such a clean and pleasant experience. Another neat detail is the derailleur and cassette are even compatible with their MTB 1×13!

Magura’s modern brake calipers, paired with Rotors levers just disappear under your hands and I’m not talking brake fade! You just don’t have to worry about anything.

In the entire length of this review period, I had no hiccups or need to adjust anything. There’s something to be said about that. Now, is it worth the price point? That’s another discussion.

Made in Spain and Take-Away

Hopefully, I don’t need to discuss the merits – and financial burden – of making products domestically. Making cranks, brakes, even frames carry a hefty price tag. The kit I reviewed is called the “1×13 Groupset Kit” and retails for €3,499.00 with one exception: Rotor built these wheels with ENVE to coincide with the made in the USA theme with the Merlin. So why is it that expensive? A lot of it has to do with the size of the company, the fact that it’s made in Spain, and it is an industry first. Hydraulic hardware has to be more precise than cable-actuated hardware and honestly, if SRAM was making Eagle or Red in the USA, it wouldn’t be far off in terms of pricing. I’m not justifying this because it’s the elephant in the room here but I’m just offering some background. Paying people a real living wage is passed to the consumer in situations like this.

Rotor offers a deal where you pay a $500 deposit and tell them when you want your kit delivered. Be it for 48 hours or 6 months. When you’re ready to pay the remaining balance, you can.

For a reliable shifting platform, with an unprecedented look and feel, there is nothing on the market like Rotor’s 1×13 kit. The only downside is the price point and yes, it’s a big one. So who is this kit for? Well, obviously, someone with the capital or credit to be able to afford it. Or perhaps someone who wants to support domestic manufacturing and wants something different. At any rate, even with the low-maintenance of the shifting mechanism, chainrings, cassettes, brake pads, and rotors all wear out. No one has found a way to engineer around that.

Merlin Sandstone

Believe it or not, this review bike wasn’t supposed to be all about the drivetrain. Merlin and I had been talking for a while about reviewing the Sandstone, the brand’s flagship gravel bike when Rotor offered to come on board. I’m glad it worked out this way too, because it really made for an incredibly pleasant and surprising review experience.

The Sandstone is a semi-custom frame, meaning while it comes in stock sizes, things like brake type and bottom bracket spec can be customized for your order. Merlin also offers custom geo, free of charge! I reviewed the stock size XL, with a moderate-sized gravel tire, even though the frame will clear a size 48mm tire. The turquoise King Headset felt fitting due to our relocation to Santa Fe, and overall, the bike is as you’d expect from one of the longest-running titanium fabricators in the USA.

What makes the Sandstone so nice is its simplicity. The cold-worked 3/2.5 oversized tubing gives it a pronounced stance, yet there’s something familiar about the ride quality of the bike. It really feels like my Firefly, aside from differences in geometry. Titanium is like that though, especially with a simple 1x drivetrain and a modest finish. There’s a classiness to a bead-blasted titanium frame that you just can’t get from other materials.


Numbers, numbers, numbers. To be honest, the only number I looked at when determining my size to review was the top tube length. I didn’t want to dive into custom geo, because I wanted to see what Merlin thought the ideal geometry for “gravel” was. The XL has a 71.5º head angle and a 72.5º seat angle, with a BB drop of 68mm. Not nearly as low as other gravel bikes on the market and that’s part of the reason why this bike surprised me so much. While most of my riding was on straight-up dirt roads, they were super rutted out and unpredictable. We don’t really have nicely-graded gravel roads where I live but I found the geometry of the Sandstone to be well-suited for riding on rutted and loose roads. Could it be the bottom bracket height? For what it’s worth, some of my favorite “gravel” bikes have between 70-72mm of drop and while 2-4mm is hard to notice, when you combine with other geometric figures, you can really alter the stability of a bike by just nudging a few millimeters here and there. Yet, keep in mind, BB drop is only one part of the whole geometric equation.

One Tight Package

You really can’t find a flaw in this bike. It’s perfect and it was as much of a joy to ride as it was to document. While Merlins aren’t incredibly flashy or adorned with custom anodizing, their construction is impeccable, the tubing spec was perfect for my 200lb ass, and when you pair the Sandstone with a buttery-smooth shifting kit like the 1×13, you really can’t go wrong. Even the 27.2 seat post shimmed in the 31.6 mm dropper-ready seat tube on this bike offered flex where it was needed.

Look at those beautiful 438mm chainstays too!

All this, with plenty of options and financing available, starting at $2,800. It’s not often a USA-made titanium frame costs LESS than the drivetrain but hey, this is a really special package!

Don’t Take This Away!

I am honored to get to ride and review bikes like this, even if they aren’t for everyone, I love that they simply exist. For me, it’s great to see companies working together to really make a dreamy riding experience, without passive or active suspension. Titanium offers plenty of flex and vibrancy without unnecessary tech. Even with the steep price point of the build kit, Merlin’s Sandstone is priced very competitively and while it isn’t flashy, you could always add paint or Cerakote to really set it apart. Merlin has been making titanium longer than most builders and it shows.

I’d like to thank Rotor, ENVE, and Merlin for assembling this beaut for me to ride, I’ll be boxing it up this week and might even shed a tear or two!

Got questions? Concerns? Critiques? Drop them in the comments…