Perched at the end of the tallest road in Slovenia, I let the bike roll to a stop to spy out over Italy’s Dolomites. Surrounding me are spires of jagged limestone jutting out from carpets of hyper-green alpine meadows. Above me, I watch the clouds fold over over Mangart’s summit.

For climbers, the summit is a beginners mountain. But for cyclists, climbing over 2,000 meters, Mangart road has gotta be one of the Alps great climbs. We spent 3 hours in the saddle get to the top (one of which was probably spent snapping photos of this amazing location). We’d spend 18 minutes on the descent.

The road to the top tucks around and through the mountain, doubling over itself as it climbs to the summit. At the top, we warm up over cabbage soup then wrestle into our jackets. All that was left to do was turn the bikes around, release the brakes and hold on tight as we took the carbon express back down into town.

This past fall Niner helped support a dream cycling trip to Slovenia. The people were kind, the food was fantastic, and the cycling … well, it was pretty fantastic too. While Tyler rode the highly anticipated MCR, which he reviews here, I swung a leg over their RLT 9 RDO. The RLT lineup (Road Less Traveled) has been around for a while; the RDO (their carbon steed) is the youngest in the pack. This year Niner updated the entire RLT family, releasing the suite with their new carbon fork, a bevy of mounting points (a whopping 26!), and wider tire clearance that can swallow up to 700x50mm or even a 650B x 2.0 tire.

The former Yugoslavian country of Slovenia served as an amazing backdrop to test the RDO. Castles, caves, toothpaste blue rivers … for a complete story on riding in Slovenia, roll on over to our Where To Ride story. In the mean time, here’s an overview of how the RDO tackled the gravel and pavement in beautiful Slovenia.

The Niner RLT 9 RDO overview

Niner originally introduced the alloy RLT 9 back in 2013. The RDO (Race Day Optimized) is their top-shelf carbon model in the RLT 9 lineup. Niner built the RDO for the rider who likes to ride fast and appreciates the ride quality of carbon. If you find yourself riding gravel centuries or ultras, the carbon will buff out the bumps over time in the saddle. And the bike feels really quick on the roads. But they also considered the average rider -someone like myself- who rarely races, but wants flexibility to bike pack, tour, or ride distances in comfort (and style).

Tech details & actual weight

The demo bike shipped running Shimano 105 2×11, with an 11-32 cassette in back. This is actually their middle of the line 2019 kit mounted to the 2020 frame. If you were to buy a comparable build with their latest groupset, it would be equipped with SRAM Rival 22 and would run you about $3,700. The top RDO build is kitted out with SRAM Force and carbon wheels for $6,600. But flexibility is what the RLT is all about. The RDO’s BioCentric bottom bracket shell can mount a 1x or even be set up as a single speed.

All RLT 9 frames are offered in 6 sizes: 47, 50, 53, 56, 59, and 62cm. I’m an average 5’10” guy with average reach and anatomy. The 56cm frame fit me fine and I appreciated 16˚ of flare on the the Easton EA50 AX handle bar.

It’s not as slack as Salsa’s Woodchipper (which flare out to 25˚) but feels very natural when toggling hand positions between climbs and descents. And descending we did. That ride down Mangart Saddle? We topped out over 40mph while whipping down the single lane military road. The bike felt stable and secure when tucked in the drops.

The RDO routes all cables internally, through the frame. I love the look of a clean frame, free of cables, and how internal routing reduces issues when strapping frame bags. But, internal routing makes my mechanic sweat. Fortunately on the RDO, internal guide sleeves feed cables cleanly through the frame so no more blindly fishing around for the cables. Your mechanic will thank you. And if you like to wrench on bikes at home, you should be pleased with how easy it is to maintain.

Furthermore, the internal routings can cleanly accommodate aftermarket mods like a dropper post and dynamo powered accessories (which runs internally through the fork). Which begs the question, would you benefit from a dropper post? Maybe, but for me, probably not. But that’s because they released the MCR, which encourages that kind of riding and a dropper post would certainly be a welcome addition to when taking it off piste.

Speaking of forks, one of the biggest updates in the 2020 lineup is Niners RDO carbon fork, available on all RLT 2020 models. Leveraging the latest Niner carbon layup, the fork comes equipped with two sets of four braze-ons that can fasten cargo cages to carry even more gear or water bottles into the backcountry.

In fact, a total of 26 braze-ons brandish the RDO, giving you mounting options for lights, cages, fenders, and racks. While we used Roswheel bags on the Slovenia ride -which strapped snug around the frame with thick rubber bands– if I was to buy this bike as my main bike, I would seriously consider ponying up for Niner’s new frame bag and bento bag. Both bolt directly to the frame’s braze-ons for a dialed fit that looks super clean.

The RDO ships with Stan’s NoTubes alloy rims paired with 100 and 142 12mm hubs.  The wheels were strapped with 700×40 Schwalbe G-one Evo SS tires. If you’re fat-curious, the stays can squeeze in up to a 50mm tire or a 2″ 650B mountain bike tire. The stock 700×40 tire felt quick on the tarmac but had plenty of traction for the forest roads we found in Slovenia.

An ideal set up would be to buy two wheel sets: a set strapped with 650b and another road ready with 700c. I run something similar at home and appreciate the ability to switch between the two.

At the core of the RDO, though, is their Optimized carbon. It’s Niner’s house-brand carbon fiber composite. Like most high end carbon bikes these days, they optimize the compaction to create a lightweight, stiff, yet compliant frame. It costs a little more than their alloy and steel versions, but you shed some weight and get a smoother overall ride. The RDO I tested, running tubeless, weighed in at 20.64 lbs (9.36kg) – sans pedals. Of course weight weenies could shed more weight with carbon bits.

Niner RLT 9 RDO ride review

If you you’ve ridden other gravel bikes, you may not notice longer wheel base. At 1030 mm (for a 56), it’s about 20 mm longer than the bike I ride at home, but fairly “normal” with a rear chainstay of 425 mm (horizontal). If crossing over to the RDO from the road (or ‘cross), this extra length will probably feel slow in the corners. But what it gives up in steering and nimbleness, it gives back in compliance, comfort and stability.

And this was all fine for me because Slovenia was about touring and exploring and exploring is a sandbox I feel most comfortable in. I was able to keep up with Tyler (mostly – see the Slovenia bloopers reel). But riding the rough sections, on broken limestone jeep roads, it was painfully nerve racking.

But that doesn’t mean it’s a slow bike. When I applied power to the crank, I felt that the bike surge – particularly on the hills – inspiring the rider to link turns through the climbs.

Bottom line? The RDO is a capable carbon bike that bridges casual bike packing to ‘pedal damn it’ centuries. In our opinion, it’s home run for those looking for a capable do-it-all bike.


  1. con on

    I contacted already Niner weeks ago, but got no answer…
    When mounting 700c x 50mm tires (on a 24i or 25i rim): whats the distance then between tire and seat tube, tire and chain stays/seat stays?

  2. Tyler Benedict on

    We definitely could have sized down one on the top tube-mounted frame bag. Unfortunately for this trip, we were basing the gear order on a geometry chart as the bikes didn’t show up until very shortly before we had to repack them for the flights…too late to call in new bags from Roswheel. But Roswheel does offer multiple sizes to fit most any frame. We’ll have a full review on those bags soon.

    • Dinger on

      If they’ve increased the clearances and added more mounts without increasing weight, it’s a win.

      I’m interested in Con’s question. With 425mm chain stays and what appears to be a round seat tube, there should be VERY little space between a 50c tire and the seat tube but the clearance looks pretty generous with what I assume is the 40c tire that is referenced in the article.


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