The Inside Scoop on Norco's Prototype Downhill Bike

Downhill racing is an intense sport that requires extreme levels of focus from riders and specific equipment. When Norco relaunched their factory team after some post-pandemic hurdles they decided to try to give their riders the ultimate downhill race bike.

The design team behind the frame drummed up their theories on the best suspension system possible: a high-pivot, six-link linkage. Development has begun on a frame that Norco believes is capable of winning a UCI Downhill World Cup.

In fact, the first test mule frame, which was much less refined than this prototype, already achieved a top 30 result at the Mont St. Anne World Cup last season. From there, they knew the mule outperformed the Range and set about getting the team onto the six-link platform. Fast forward to July 6, 2023, when the team took part in a test camp aboard a freshly built prototype. A mid-season test camp might seem abnormal, but Norco saw a few reasons to take advantage of the downtime from racing.

First, the small batch of twelve frames pushed the manufacturer to produce a top-quality aluminum frame with high tolerances at every machined surface. The engineers also wished to receive real-world feedback on their suspension design, plus the hype around the frame also aimed to boost the riders’ morale and confidence. That seemed to do the trick, and the unnamed prototype went on to sweep the top-3 steps of the podium this year at the Canadian National Downhill Championships.


The design team and riders

The people behind the prototype are composed of two groups, the Factory Team and the designers. An all-star, all-Canadian list of team riders such as Mark Wallace, Gracey Hemstreet, and National Champion, Lucas Cruz were instrumental in providing feedback from their time spent on the Range. Feedback from their mechanics, Lewis Kirkwood, Jeff Hunter, and team manager, Darren Burns, didn't go by the wayside either.

Another paramount member to who provided feedback, and is literally putting the pieces of the puzzle together is engineer Kirk McDowall, who also happens to have a pair of Canadian National Champ titles on his resume. Kirk has to the skills to relay what's happening on paper with qualitative findings on the bike.

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How is this prototype different from the modified Range?

This refined test sled has a full 200mm of travel, is made of aluminum, and runs on mixed wheels only. Most importantly, this is an entirely new suspension design from Norco that builds on their findings from the Range. The process to get to this point has been an evolution of high-pivot suspension design that started with the Aurum HSP.

Although the new downhill prototype still uses a high-pivot and floating chainstay, like the Range, the lower link no longer rotates around the bottom bracket and directly drives the shock. Instead, the lower link mounted to the front triangle and the chainstay also drives a pushrod link that actuates a further upper link that drives the shock. That pushrod link rotates on two spherical bearings to isolate the link driving the shock from lateral loads

The Range is a sophisticated enduro bike with 170mm of travel designed to pedal uphill and rally on the descents. Norco’s engineers felt that they had reached the limits of what they could do to maximize the Range when trying to transform it into a full-on downhill bike. Changing one element of the kinematics had a less desirable effect elsewhere. The six-link allows the suspension kinematics to be tuned with less dependence on one another. They’re keeping those specifics, like the leverage ratio, axle path, and geometry closely guarded.





Why aluminum?

Norco opted for an aluminum frame for two main reasons. One is the durability against impacts, especially considering they only produced ten prototypes. Carbon fiber can endure high forces but often aluminum can take more of a battering. An alloy frame can be visually inspected after a crash, giving mechanics and engineers peace of mind, whereas carbon can hide the damage.

Number two would be the ease of altering angles and pivot locations as the prototype evolves. A carbon frame is confined by an expensive mold, another learning experience that limited evolving the Range in DH-mode.

On the outside, the frame looks smooth and solid, but a closer look reveals that huge pockets of material have been machined out to save weight, particularly, the shock tunnel and rear stays.

The prototype is no less complex than the Range when you start counting the linkage components and hardware, but Norco hasn’t burdened the team mechanics when it comes to wrenching on those bolts. Cutouts in the seat tube braces offer access while other features, like fully external cable routing make swapping frame members less of a chore. Even the shock placement was considered in order to cut down the mechanics’ workload.

Visually, the bike had to appeal to racers too. That challenged Thadeus to first meet the locations of the pivot points and shock placement, and work with the manufacturer to meet the strict tolerances - a tenth of a millimeter here or there can change the head angle or leverage ratio significantly.




Ride Aligned expanded

Norco left no stone unturned when it came to data acquisition. Building on their elaborate Ride Aligned morphological suspension setup, the engineers developed their own front and rear telemetry system, ordered up a fancy shock dyno, and even have a set of expensive scales to measure the rider’s weight distribution between the axles. Those bosses on the downtube aren’t for a water bottle, though. Instead, they serve as a secure mounting point for the brain of the telemetry system. Behind the stem, there’s also a GPS unit to track the bike’s every move too.

As it turns out, three of the four riders providing feedback on the platform are nearly the same height so only one front triangle was needed for Mark, Kirk, and Lucas. The geometry differs from any production bike sizing and offset headset cups tailor the fit for each one of them.

Through testing, an air shock was largely favored, in particular, a prototype from RockShox. One reason for this was the ability to minutely change the spring rate, instead of the large jumps between coil springs. Another consideration was the percent error associated with the true spring rate of coils which can have a pronounced effect on lighter riders like Gracey.


What about 29” rear wheel options?

Norco was also open-minded about the testing. What falls short for their downhill requirements might actually be a positive attribute for trail bike development, and vice versa. Take for example how adamant Norco was about using a 29” rear wheel on the Range. They explained that the frame's kinematics and balance were designed specifically around the larger wheel size and shouldn’t be meddled with.

As the trend of mixed-wheeled downhill bikes began to rise, Norco set out to test back-to-back between the two rear-wheel options. A 27.5” rear wheel made sense for Gracey Hemstreet as a smaller rider. The other tall riders on the team agreed that the smaller wheel allowed them to make quicker direction changes. That solidified the decision to base the kinematics for the prototype on a mixed-wheeled platform.





Future plans

From here on out, there’s no production scheduled for this frame. Norco’s goals are aimed at creating a platform for their racers to get down the hill as quickly, and confidently, as possible. They’re taking a “Formula 1” approach to developing this bike on the fly throughout the season and gathering valuable feedback along the way.

We’ll keep an eye on the development of the bike and continue to report any findings.

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Reviews and Tech First Looks DH Bikes Norco Norco Prototype