Swiss Gravel: Thömus Sliker X Review

Thömus Bicycles may be a new logo in the United States, but the Swiss brand has been manufacturing bikes since the 1990’s. Now, almost 30 years later, we’re seeing them in the USA. With a subset of their full lineup, Thömus USA will count on the Sliker X gravel bike as a gateway for the brand to gain popularity in the States. In for a limited test, this racy gravel bike has been a zippy change of pace from the Salsa Journeyer I’ve been riding.

Thömus Slicker X Features:

• Compatible with 1x or 2x drivetrains
• Comfortable endurance/gravel geometry
• Internal routing for a clean look
• Massive 50c tire clearance
• Race-focused with minimal mounting points
• Integrated axle inserts
• Weight: 19.8 lbs (large, as shown)
• MSRP: $5150 – $6799 (SRAM Rival XPLR or Force 1x)

Build specs and setup

Admittedly, until a few weeks prior to getting the Thömus Sliker X, I had no clue that the brand even existed. As one of the millions within that camp, I didn’t know what to expect, but after a few weeks aboard this racy gravel bike, I now know that speed and responsiveness are core to the brand and its bicycles.

On paper, the Sliker X has quite a long reach and tall stack height in the size 56cm. And, that shallow 71-deg head angle would seem to add to the relaxed nature of the geometry — at least on paper. A proper fit required removing all the spacers and switching to a different saddle on the zero-setback 31.8mm seatpost. Even that didn’t get me all the way to my preferred position (15mm lower stack would be needed), but it was close enough and proved to be helpful in the long run.

As tested, the Sliker X came equipped with a full Shimano Ultegra Di2 groupset with compact 50-34t chainrings 11-34t cassette. HED Emporia alloy wheels and Schwalbe G-One R tires can be found on the stock Rival XPLR kit in place of the racy Schwalbe G-One RS tires on this test build. Further, the awesome Thömus carbon handlebars on this bike remain an elusive mystery (which I’ll attempt to solve). You’ll find stock builds will come with FSA cockpits and, as mentioned start at a reasonable $5150 from the US headquarters in Santa Monica, California.

Due to the short turnaround with the bike, I kept the tubes in place and didn’t convert to tubeless. The combination of the heavier wheels and tubes did yield a disappointing 19.8 lb bike weight. Digging into that, the stated frame weight is 1180 grams, so it’s not going to compete with lightweight 880 gram Open UPPER frameset, and it’s 140 grams heavier than the comparable Open WI.DE. frameset. As I found, the Sliker X carries that extra weight well and (mostly) only comes into play on the scale.

Sliker X is a wolf in sheep’s clothing

Once ready to ride, I took the Sliker X on a quick test lap around the park. My immediate impression was that in spite of the forgiving geometry on paper, this bike feels very racy. The short, 90mm stem and fast-rolling Schwalbe G-One RS tires give the bike a zippy feel, but how would that translate on the gravel?

As I ventured into my normal gravel terrain, the zippiness I felt on the road immediately came into play. On rolling, smooth gravel, I was flying. Since the frame doesn’t have any notable aerodynamic queues, I can only attribute that speed to the fast-rolling tires, the geometry, and the efficient power transfer to the wheels. Subsequent rides did show that this bike, as configured is pretty fast. While I didn’t nab any PR’s, most of the segments where I intentionally stepped on the gas did hover among my top times. This was in spite of running higher tire pressures than I would prefer.

With 50c tire clearance, you can outfit the Sliker X to tackle aggressive terrain. But, even with the 40c tires running 43/41 psi., I was impressed with the comfort of the Sliker X. And, that impressive comfort is also in spite of a large-diameter 31.8 seatpost as well. With lower tire pressures of a tubeless setup, I would expect even more speed, comfort, and an added dose of traction — which the racy G-One RS treads desperately needed.

Not only did I ride the Sliker X on smooth gravel, I took it into a variety of singletrack trails that are typically ridden on a mountain bike. On more aggressive terrain with loose rocks and challenging obstacles, the tires did limit how aggressively I could ride and climb. While I didn’t notice the quick handling as much on smooth gravel, it became a distraction on technical trails and required me to slow down and tackle them more conservatively. Like a fine race bike, the Sliker X requires an adept handler because that front wheel responds much faster than your typical gravel bike. You only have to think about turning and it’s responding. That responsiveness does make the bike feel more playful and lively when hitting small drops or berms though.

I appreciated plenty of toe clearance on tight turns on the trail and road. And, the bike feels balanced for hands-free affairs on the road. But, on switchbacks, I did feel like I was fighting the front-end just a little because of its eagerness to bite into the turn faster than intended.

When it comes to climbing, I was concerned that the fast handling could translate into a wandering front-end on the steepest climbs. To combat this, I was able to easily move my weight forward on the Ergon SR Comp saddle to maintain the proper balance. In addition, the 1:1 gearing required that I maintain more speed on those climbs, which helps too. On more normal grades, I found the Sliker X to be a great climber that allowed me to pedal in the saddle at a smooth cadence. Though standing climbs did reveal the lack of traction provided by the G-One RS tires.

On the road, the Sliker X feels like a proper road bike. It handles adeptly and responds in kind. When racing down winding descents, you need to stay on top of it because that responsiveness shines through in a big way. Very little steering input is required to angulate and rocket through any turn. If you’re coming from a road background, it’s a blast, but keep an eye on that oversteer. A 100 or 110mm stem could help slow that down a little.

I was surprised how well the Shimano Ultegra Di2 groupset performed on gravel. While you won’t necessarily outfit one that way, it can hold its own. Still, if I was going to opt for a Shimano build, I’d go with GRX because the levers are gravel-optimized and chain retention is better. If you ride gravel on occasion, but want a versatile endurance bike, Ultegra Di2 could be considered. And, I would definitely opt for a 160mm rear rotor for added braking power because the 140mm rear left me wanting more bite.

I can’t wrap up the review without mentioning the house-brand Thömus carbon drop bars on this bike. Sadly, I don’t know anything about them other than what I can see. Google searches are yielding nothing and I’m awaiting more details from Thömus, but the shape is spot-on. I love the ovalized tops with added backsweep and the extreme angle that they make towards the hoods (much like the ENVE SES AR drop bars). In addition, the compact drops have just the right amount of flare for added control. I measured them at 42cm wide, but they feel wider than that (I typically ride 44cm).

Fit: at 5’11”, I have been testing the size “Large – 56” Sliker X, and, after some finagling, I think it’s a good fit overall. I would prefer about 15mm lower stack height and a 100mm stem if I had this bike long-term.

The Good:

• Responsive and fast gravel racer
• Very comfortable — in spite of still running tubes at higher pressures
• Forgiving geometry offers a more upright body position
• Looks awesome (my kids have all commented on the red color)
• Sleek, integrated axle threads
• FSA stem offers clean cable routing that affords some adjustment
• Unique brand that stands out from the crowd
• Thömus-branded carbon drop bars are awesome (and should come stock)
• Great for endurance road use
• Massive tire clearance

The Bad:

• Handling is very racy — stay on top of it
• Tight turns can feel like you’re fighting the bike a little
• Hard to get the right stack height with the included spacers
• Not many mounting points for adventure-riders

The Bottom Line: Thömus Sliker X

As one of the key bikes that Thömus is counting on here in the USA, the Sliker X will find a home among gravel all-road riders who appreciate road-like handling in their gravel bikes. With plenty of comfort as-is, going tubeless and/or opting for larger tires will both add to that comfort and make it even more capable. This is a fun, racy gravel bike that responds like a champ when pushed hard on the gravel or road.

Buy One: Visit Thomus.com