The 2019 Norco Aurum HSP carbon downhill mountain bike gets its acronym from the new High Single Pivot design. This puts the chain path along the seatstay to prevent the massive chain growth that would otherwise occur with such a design, but there’s more to this bike than just a unique drivetrain layout.
The carbon frames proved tough enough for their pro athletes, who ran the same frames from start to finish throughout the 2017 season. Cables run externally to make parts swaps and repairs easier. Even the cable path was considered, angling out of the way of race number plates so you don’t have to cut them to lay flat.
Up front is an adjustable headset cup system, but it changes the front center (and wheelbase), not the head angle.
Called Gravity Tune, the HSP design creates a rearward wheel path that lengthens the wheelbase under deep compression. They say this keeps the rider centered on the bike and improves control and handling. The idler pulley at the top of the system creates a parallelogram chain shape, which is what keeps it from affecting suspension movement.
The long chain path is kept away from the carbon with a rubber frame guard.
The linkage system gives them control over the leverage ratio throughout the travel. Proper setup is key, so they include a detailed suspension setup guide with each bike.
Besides clean looks though, the other trick up its sleeve is that there are dedicated 29er and 27.5 platforms, offering wheel size-specific suspension kinematics and layout, but both use the same HSP design. The 27.5″ bikes will come in XS/S, S/M, M/L and L/XL sizes. The 29er only gets the two larger sizes. Two build specs are offered, the Aurum HSP1 with SRAM X01 DH group, Rockshox Boxxer World Cup & Super Deluxe Coil, and DT Swiss wheels. The Aurum HSP2 gets SRAM GX1 7-speed, Boxxer RC and WTB/Novatec wheels. Pricing TBA closer to their mid-summer availability.
2019 Norco Search gets a dropper option
The Norco Search gravel/all-road bike carries over with the same frame, but does get a very slick stock spec on the top-level Search XR Force 1 build. For $4,199, you get a full SRAM Force 1 group using the Quarq Prime cranks (which you can easily add a powermeter to later on) with hydraulic disc brakes, and the left shifter lever has been rerouted to operate the 65mm travel KS LEV Integra dropper seatpost.
The carbon frame comes with an integrated chain catcher and a mix of WTB, Maxxis, DT Swiss, and Easton parts.