Steamrolling trail machine.
Outfitted with the trail-smoothing ability of voluminous 2.8-inch tires, the Niner Air 9 27.5+ 1-Star NX Complete Mountain Bike provides unparalleled traction and bump compliance for a hardtail lacking the sophisticated suspension of its full-squish brethren. It's a great choice if you regularly encounter rocky trails and root-latticed forest networks that would normally buck you silly on older hardtails lacking plus-sized tires and a longer 120-millimeter fork. Ultimately, the Air 9 27.5+ is a solid upgrade if you're ditching your beat-up mountain bike from ten years prior or you're moving to more progressive trail geometry from a racier (i.e. stiffer and more uncomfortable) cross-country bike.
Niner starts this build with a hydroformed aluminum frame that creates a lightweight ride with excellent trail feel. Using a multi-staged hydroforming process, a straight tube is butted and mechanically formed in preparation of the hydroforming process. Up next is multi-stage hydroforming, which is a series of molds used in sequence to create complex shapes. Multiple steps might take Niner longer, but they're able to reduce weight and achieve a higher strength. Hydroforming uses molds and fluid pressures to form metal tubes into shapes ideally suited for certain locations along the bike frame, meaning Niner can dial in the bike's riding characteristics exactly how they'd like.
Besides using a hydroforming process to create a remarkably strong and relatively lightweight aluminum frame, the AIR 9 27.5+ comes with more progressive trail geometry that's a sigh of relief if you're transitioning from an overly stiff and twitchy handling cross-country bike. Considering its head tube angle of 68 degrees, it'll handle the rough stuff with greater composure and descend confidently without trying to chuck you over the bars. However, it's still highly efficient at pedaling back uphill and covering large swaths of terrain, seeing it's not as slack as many of the trail bikes on the market. Sub 17-inch chainstays (16.9 inches to be exact) breathe agility and cornering prowess into this trail bike, meaning you'll have a blast railing berms and finally clean those tricky uphill switchbacks.
This 1-Star NX build outfits the bike with 2.8-inch Maxxis Rekon+ tires that absolutely steamroll anything lying in their path, allowing you to ride over loose rocks, bumpy roots, and other impediments that would normally leave your wrists feeling like you're operating a jackhammer. Besides smoothing out the ride, plus-sized tires actually grip a lot better over loose soil and chunder, especially if you drop the tire pressure according to your body weight and local trail conditions.
Another notable features of this build includes a 120-millimeter RockShox Judy Gold Fork that offers more leeway for riding technical trails, especially if you're comparing it to hardtails with only 100-millimeters of front travel. Additionally, it's boasting a simplified SRAM NX 1x11 drivetrain, which provides plenty of usable gears with its larger cassette, even when you're pedaling up steep grades that would normally cause you to drop into your front granny ring.
- 27.5+ hardtail confidently rolls over anything on the trail
- Plus-sized tires smooth out rocks and provide gobs of traction
- Modern trail geometry is more relaxed and confident on descents
- Geometry remains efficient under power and nimble around corners
- Compatible with Niner Biocentric 30 for converting to singlespeed
- Internal dropper post routing makes it a solid platform for upgrades
- RockShox Judy Gold 120mm fork provides ample travel for rough trails
- SRAM NX 1x11 drivetrain ditches pesky front derailleurs for good