Merida O.Nine 3000D review

Ultralight carbon hardtail

Our rating 
4.0 out of 5 star rating 4.0
GBP £2,999.99 RRP

Our review

The lightest production hardtail frame and butt-saving comfort in one sweet package
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Merida reckon the O.Nine is the most technically advanced carbon hardtail frame ever made. Such spiel is one thing, but it’s the seat-of-the-pants reality of riding a bike that really matters. We could name a stack of ‘best ever’ bikes from top brands that have turned out to be average once we’ve got them on the dirt.


So how does this effort fare? The O.Nine is a bike for dedicated but progressive thinking cross-country riders, or marathon racers looking for that magical combination of instant drive and a smattering of full suss-style comfort.

The frame is bloody light – just 935g – but the bike still handles the bumps well. We’d like to attribute this to the chassis, but it’s probably more down to the tuned flex of the seatpost, the comfy saddle and floaty tyres. We’d be happy to own a 3000D, because we know it’s a bike that’s working hard to let us play hard.

Ride & handling: Trail-smoothing cross-country rocket

Once we’d ditched the crazily long 110mm stem for a 90mm model, the O.Nine took off at a pace that would normally have us gasping. Admittedly, you’d expect a 935g frame to feel quick, but even kitted out with sensible spec Shimano Deore XT kit rather than high-end XTR bits, the bike accelerates like it really wants to impress. It’s got legs and it likes to stretch them.

It’s not the frame that really grabs your attention, though. It’s the carbon seatpost, which has been designed with a degree of fore/aft flex to improve comfort and seated control. We launched into the long gradual climb up a rocky unmade road that’s part of our regular cross-country test loop, and we appreciated the long top tube’s ability to flatten our back and generate a sense of power. But after picking up speed, we were able to remain seated and keep the taps full open while spinning happily as the bike soaked up the bumps.

This is the kind of terrain where any other carbon hardtail (save the Cannondale Flash we tested at the end of last year) would have had us butt clenching until a smoother surface appeared. We swapped the Merida seatpost for a regular alloy post known to have minimal deflection – repeating the same climb at the same speed while using the same tyres at the same pressure – and that resulted in us resorting to ‘the clench’ when trying to match the speeds we’d managed with the Merida post.

Just to further define our findings, we also used the flexing Merida post in another carbon hardtail that’s known to be a super-firm ride. And would you believe it, the bike suddenly developed a taste for bumps? To be fair, it’s not just the seatpost doing the magic here – the O.Nine frame does have a degree of vertical compliance in it too – but the post is at least three-quarters of the overall feel. What does this mean in real world? It means you can ride this hardtail harder and faster than nearly any other, with only Flash owners likely to worry you.

Frame & equipment: Cutting-edge chassis plus sturdy component spec

Well, for a start, the frame is light. The O.Nine is so called because its modest 935g weight is close to the company’s goal of a 0.9kg frame. To achieve that amazingly light weight, Merida use a tube-by-tube design to produce a ‘structure element’ construction, whereby each tube is given a specific set of goals. For instance, the top, head and about half of the down tube are made in one complete piece, because they sit in an area where joins aren’t ideal.

As well as making the O.Nine light, Merida have looked at making it as vertically compliant as possible. This is because an increasing number of pro cross-country racers are asking for race-ready hardtails that have a greater nod towards the levels of comfort they could expect from a short-travel full suss bike. Thus the pencil-thin flattened seatstays and square-to-round Flexstay chainstays are said to tune out some of the high-frequency buzz that keeps hardtail riders hovering over the saddle.

All that’s topped off by a rangy top tube mixed with beefy head and down tubes, which give the O.Nine a chunky and purposeful look. Parts wise, the XT transmission is nigh-on faultless, the Magura Louise brakes are strong if a little clunky looking, and the DT Swiss X1900 wheels are sensibly built with durability placed before gram dodging. The use of Schwalbe Rocket Ron 2.1in tyres provides a good blend of float, grip and low rolling resistance. A special mention must also go to the very comfortable ProLogo Scratch Pro Titanium saddle, which was perfect.


The fork is a Fox F32 RL 80mm-travel job, which must make Merida one of the last companies to spec an 80mm fork. That said, it’s a quality 80mm of travel and we bounded along some less than smooth trails without feeling we were undersprung. Even so, we’d have liked 100mm, just to provide insurance against the bump we never saw.

Merida o.nine 3000d: merida o.nine 3000d
Seb Rogers

Product Specifications


Name O.NINE 3000D (10)
Brand Merida

Brakes Louise 160 / 160mm
Cranks XT 44-32-22
Fork F32RL 80mm
Frame Material Merida O.Nine Carbon Nano Ultralite
Front Derailleur XT
Handlebar FSA XC 180OS Flat 620 bar
Head Angle 71
Rear Derailleur XT Shadow
Saddle ProLogo Scratch Pro T2.0
Shifters XT rapidfire
Stem FSA OS-XT 6° stem
Weight (kg) 10.1
Front Wheel DT Swiss X1900
Rear Wheel DT Swiss X1900