The All New Norco Aurum HSP DH Bike

When Norco released the original Aurum in 2012, it brought a new direction in both aesthetics and design. Norco's lineup of trail bikes slowly took on cues from the DH bike and with it, a reinvigorated brand was unleashed. The progression resulted in improved geometry, suspension design, and even graphics. 

Now Norco has released one of their most radical designs to date. The Horst Link suspension of the previous Aurum has been replaced with a High Single Pivot. It's a race-bred machine, built with close attention to the needs of Norco's World Cup team. Raced and tested by the team for a full year, the 27.5” wheel version has been well sorted. Team riders are also posting some great results on their 29-inch wheels this year. The final production-ready bike seen here is the culmination of their experience and feedback.

Features

• Full carbon frame 
  
• Gravity Tune: Ensures optimal body position and ideal weight distribution for riders of all sizes. 
  
• A.R.T Suspension (Advanced Ride Technology)
  
• Adjustable Front Centre: Quick and easy setup and fit tuning with an adjustable headset cap system
  
• 650b or 29-inch wheels: 29er only available in the M/L and L/XL sizes
  
• 200mm of travel front and rear, in each wheel size
  
  

Model Range

The Aurum HSP is available in three options. I'm testing what is essentially the World Cup replica and it features everything that the Norco Factory Race team runs with the exception of the wheels.* It’s literally a dream build with everything from the World Cup Boxxer and SRAM’s X01 DH-specific drivetrain to the Deity components run by the team. The bike comes with a price tag at the upper end of the scale; 7,999 USD (9,499 CAD).

Aurum HSP1 Specifications

• RockShox Boxxer WC (Boost 20x110)
  
• RockShox Super Deluxe RC Coil Shock
  
• SRAM X01 DH Drivetrain
  
• SRAM Code RSC Brakes
  
• DT EX511 Rims
  
• DT 350 Hubs
  
• Schwalbe Magic Mary DH (Addix Ultra-Soft)
  
• MSRP: 7,999 USD (9,499 CAD) / Frame: 3,299 USD (4,299 CAD)

*The factory team uses Novatec wheels. The stock build is fitted with DT EX511 rims built to DT’s 350 hubs. 

The HSP2 comes with savings between 2.5K and 3K, depending on your region. It retails for 5,499 USD (6,499 CAD) and fetches an impressive build with the same, full carbon frame. Suspension duties are taken care of with the same rear shock while a Boxxer RC takes care of the impacts at the front wheel. The brakes are stepped down to the Code R, gearing is taken care of by the GX DH specific drivetrain, and the wheels are a mix of Novatec and SRAM hubs laced to WTB i29 rims with DT Competition spokes. Race Face takes care of most of the touch points. 

Retail for the frame only option is 3,299 USD (4,299 CAD) including a RockShox Super Deluxe RC coil rear shock, a headset, reach adjust inserts, and a Syntace X-12 rear axle. 

Frame Design

The earliest rideable versions of most new frames are made of aluminum. These 'mules' are tested and tweaked in various iterations to make sure everything is perfect before the expensive process of opening tooling for the final carbon frame. In contrast the Aurum HSP went straight from concept to carbon which, Norco tells us, was necessary because of the combination of leverage ratio, geometry, and frame design. 

Working closely with Norco Factory team riders including Sam Blenkinsop and the factory mechanics, Norco established the must-haves early on. A race-bred machine, the HSP was designed with mechanics top of mind. It includes a locking main pivot, full external routing fixed with small bolts and alloy clips rather than zap straps, and has optimized space for race plates.

Norco's "Gravity Tune" philosophy continues with the expansion of size specific frames and tuning. The Aurum HSP features a rear-centre (chainstay length) that grows with each size increase, something Norco has been doing since the first Aurum was released. Frame compliance varies between sizes, with construction focused on delivering optimal ride feel across the range. This is rather than perfecting it for say, the size medium and using the same dimensions for other sizes. To do this tubing profiles vary across the range. 

Norco realized that riders may want to adjust sizing for different tracks or rider size. With this in mind, the Aurum HSP is built with an elongated cavity in the head tube. The use of two different chipsets allows the bike to run at the stock reach measurement (shortest option), or +3.55/+7.1mm with the use of the second supplied set.  

Suspension Design

High single pivot bikes generally result in a rearward wheel path, allowing the wheel to more easily move out of the way of impacts. The design often results in a bike that maintains momentum in rough terrain but these bikes haven't been overly successful with consumers. One downside is the rearward wheel path generates a lot of chain growth and significant pedal feedback. The use of an idler pulley above the pivot minimizes the effects of the chain on the rider. Its placement is important and as some may have noticed, current World Cup points leader Amaury Perrion has had the idler on his Commencal moved from race to race. Each change affects the amount of anti-squat in his bike's rear suspension. 

Combining Norco’s A.R.T. suspension with the HSP has resulted in what is being referred to as the "most extreme iteration of the A.R.T. Suspension philosophy.” The idler pulley's placement reduces pedal feedback while providing the most grip and support possible. 

Geometry

Faster tracks produce higher speeds. Add the world’s fastest racers pushing for more and the importance of geometry is absolutely key. The Aurum HSP features a relatively aggressive geometry and between wheel sizes, nothing in terms of head angle or length changes much. My L/XL 29-inch Aurum HSP test bike is a few millimetres shorter than the equivalent 27.5-inch wheeled bike. 

Head tube angle measures an aggressive 62.5 degrees and on the L/XL, reach is 461mm for the 29-inch version, 4mm shorter than the 27.5. Clearance is impressive and the L/XL standover measures 787mm. The head tube on the 29-inch models are tiny, measuring 100mm – the same as the XS/S 27.5. This keeps the stack in check when jumping to the bigger wheels, and it measures 617mm; just 5mm taller than the L/XL 27.5 bike, with room to move.

Norco's size-specific geometry continues to evolve and the rear-centre of the Aurum HSP bikes grows 10mm between each wheel size. The L/XL test bike has a 430mm chainstay. It’s still relatively short, especially for a DH 29er with 200mm of travel. Throughout it's travel the Aurum HSP's rear-centre grows between 35 and 38mm on the L/XL. At full travel, this equates to a 465mm rear-centre on the 29er (468mm on the 27.5).

Initial Riding Impressions

Off the bat, the rear suspension on the HSP felt incredible. “Commuting" from the Whistler Bike Park’s Creekside Gondola down Expressway toward the top of Fitz chair, the point was proven instantly. The eyeball rattling chatter of the road was virtually absent. The comfort meant speeds got higher and while clocking ~60km/hr around a bend toward Too Tight, the bike remained calm and composed. 

Dropping into Too Tight my impressions remained positive. Despite the big wheels, the bike danced through the twists and turns with only my own mistakes to blame for any loss of speed. Popping out of the trail, I headed straight to Garbo chair for more. 

Across the upper section of Freight Train, the HSP saw its first shot of air. It was stable and soaked up a lot of the lip during lift-off, something that some park-rats may not enjoy, but is easily tuned for with either a bump up in spring-rate or some adjustments to the damper. Personally, I enjoy a bikes ability to remain composed in the chop and the HSP was doing this in spades. Original Sin was smooth as ever, as was the rest of the run. Traction is excellent in all situations, instilling confidence on any trail feature encountered. 

As of writing, the only real downside to the bike is its size. Reach numbers and wheelbase feel a little short for the biggest frame-size. My 191cm of lank feels cramped, even with the extension installed in the head tube. A number of competitors in this category are hitting the 480–500mm reach range and getting close, or even touching the 1,300mm wheelbase. I'm left to imagine how that may feel with this bike…  

The majority of adjustments during the initial ride were made at the front, with the Boxxer not equaling the performance of the rear. High-speed compressions were harsh, sending adequate feedback through the hands. Since that first ride the Boxxer has been opened up and the two tokens that were fitted stock, removed. It’s a move I’ve found myself doing more lately, with the larger negative air springs allowing for it. It’s also a recommendation in Norco’s tuning setup guide, based on my body-type, weight, etc. Damper settings remain similar to the initial setup and pressure has been adjusted for a hair more than 18% sag. Hopefully the fork will better match the amazing bump eating of the rear for the next outing. 

Head to the Norco website for more information on the new Aurum HSP. Check back to the site for a full review soon.