NS Bikes has expanded its Define range with a new mullet option.

Although the mixed wheel size is popular on e-bikes and in the downhill racing scene, there aren’t too many standard single-crown fork frames offering it.

Sensing the opportunity to deliver something on-trend for its customers, NS Bikes has launched the Define AL 170. Built around the brand’s 170mm Define frame, it uses the latest 38mm stanchion single-crown forks up front, housing 29er wheels, to deliver terrain rollover, whilst the 27.5” rear wheel amplifies agility.

Read more: best enduro bikes 

With this new Define variant targeted at adventurous bike park riders, NS Bikes chose all-aluminium construction, in the interest of impact survivability. Geometry numbers are what one would expect for a long-travel enduro bike with bike park capability.

The Define AL sits at a 64° head angle, with a choice of Fox 38 or RockShox ZEB forks, all at 180mm of travel. On a size large, there is 480mm of reach and all frame sizes have the same 438mm chainstays.

You can adjust the geometry even more

For those enduro and bike park riders who wish to customize or experiment with their geometry, the Define AL has a flip-chip, which slackens the bike by half a degree, drops the bottom bracket height by 5mm and trims 4mm off the reach.

Standards and industrial design details on the Define AL tally a durable threaded bottom bracket, ISCG tabs, an integrated 1.5” tapered headset and sealed MAX bearing pivots, which should better absorb large lateral forces over time.

Although most of the cable routing is external, it runs in a neatly grouped channel on the downtube, with a lower frame protector covering. The  Define AL’s rear triangle is spaced to roll 27.5×3” tyres without any mud clearance issues.

The Define AL 170 coil suspension option – is cheaper

There are two build options available. The AL 1 170  enduro+ is equipped with a Fox 38 Performance fork and X2 air shock. It decelerated via SRAM Guide RE brakes, actuating 200mm rotors, and the drivetrain is GX Eagle.

If you prefer a coil at the rear the Define AL 170 2 runs a RockShox ZEB up front, with X-Fusion’s Vector R coil between the rocker link and bottom bracket. Shimano provides a Deore drivetrain and MT420 brakes for this value enduro mullet build.

The weight difference between these two extreme enduro bikes is negligible, with the Define AL 1 at 15.5kg and the much cheaper Define AL 2, at 15.8kg. Respective prices are €4500 and €3400.