The Razorback was originally destined to be K2’s first hardtail, then, with the suspended push shock linkage design licensed from Turner, it evolved into a full bounce bike. With K2 now developing their Noleen shocks and forks, the Razorback loses the leading link fork and coilover rear shock, along with a fair bit of weight, and gains Easton main tubes, telescopic air forks and an air- sprung rear push shock.
|Frame||Butted 7005 T6 Easton|
|Fork||Noleen Mega Air|
|Stop||Avid 25 V’s and XT STI levers|
|Go||XTR rear mech, XT elsewhere|
|Wheels||32-hole XT hubs, Sun O Lite rims and
Panaracer Fire XC Pro tyres
|Stuff||Easton EA70 seatpost and handlebar, Titec
stem and grips, SDG Bel Air saddle, and K2 clipless pedals
|From||Ultrasport 0115 9731001|
But nowhere is componentry compromised to save weight; you won’t find 1.7in tyres or harsh saddles here. All this weight saving brings the Razorback into the league of the XC racer as well as the all-day trail rider.
The butted 7005 T6 back end pivots above, and behind, the bottom bracket and plugs into the Noleen Mega Air shock which is anchored halfway up the seat-tube. The Easton Ultralite downtube is ovalised horizontally and vertically at the bottom bracket and headtube respectively. The headtube is ring-reinforced, and the seat-tube reduces in section to accommodate the 27.2mm Easton post. Disc mounts are included on the fork and the universal mount above the rear drop-out, which is part of the chainstay beam, so no Horst link as that would need another licence. The production version will feature hydraulic cable guides and metallic paint on the rear end.
The ride is very smooth and stable; the rear quarters remain stiff under acceleration thanks to square section seatstays and a cast pivot-yoke. Seatstays start round in section at the drop-out and taper into a square section up by the shock mount – a fine piece of tube profiling that adds lateral rigidity to the rear end and reduces sideways shearing forces on the shock body. Rear travel feels tight at first, but dial in a generous amount of sag and it will happily work mid-travel over most terrain. Rebound is best set about half to three quarters of a turn from slowest to prevent aggressive top-out. Perhaps the best feeling we experienced from the K2 was that of landing mid-sized drop-offs at speed onto broken ground where the bike stayed level and touched down smoothly with a good balance between front and rear suspension. Lock out the Razorback with the bar-mounted thumbshifter and it behaves like a stiff hardtail rather than a lump of locked up suspension bike, but the shock is still ready to give a little under the hardest of hits. It’s a good idea to check the cable for stretch after hard use to makes sure that you’re getting full lock-out.
Noleen’s telescopic Mega Air fork sits up front holding the front wheel effectively on course with the help of a wide crown and large diameter legs. The absence of a negative spring means there’s a little stiction, but the forks were overshadowed by the smoother rear end. Otherwise, they performed well, adding to the overall solid feel of the bike. A minor niggle we had was with the recessed top caps which tended to collect water and dirt, not good around uncapped Schrader valves.
Looking closer into the componentry package it’s easy to see where weight has been saved – Easton provide seatpost, bars and titanium bottom bracket (a great deal lighter than steel-axled units but needs regular checking and tightening to stop it creaking). Sun O lite rims on XT hubs make the wheel package light and strong. The groupset is XT, so no complaints there, broken up by XTR rear mech, and Avid 25 V’s offer yet more gram shaving.
A solidly built bike with a thoughtful mix of durable ‘rider’s choice’ components
and weight savers. Air shocks might not suit those used to the plush linear rates
of coil springs, but still deserve a good thrashing and will please with floaty,
smooth moments. Paint job is attractive and well coordinated, and fine detail is
only let down by the tinny bolt on seatstay bridge.