Norco is Testing a 6-Bar High-Pivot Downhill Bike with Hemstreet & Cruz

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Gracey Hemstreet, Lucas Cruz and Mark Wallace have been testing an all-new prototype aluminum downhill bike from Norco, featuring a 6-bar linkage suspension layout. And, Lucas Cruz just won the Canadian Downhill National Champs aboard his. Here’s what we’ve gleaned so far.

Norco’s Prototype 6-Bar Linkage Downhill Bike

Happily, a trip to the Norco website yielded a host of detailed studio images of the prototype downhill bike – with telemetry. Credit: Norco.

Until now, Gracey Hemstreet, Lucas Cruz and Mark Wallace have been piloting the Norco Range DH at UCI Downhill World Series events, which is essentially a long-travel version of the Range Enduro Bike, adapted for the demanding tracks with a 200mm travel dual-crown fork and a longer stroke shock. Now, it seems, the team is to benefit from a dedicated downhill bike that runs an all-new suspension design.

Also, that 200mm fork is sporting some not-so-sneaky RockShox Blackbox decals, suggesting there’s some prototype stuff going on inside this Boxxer. More on that down below.

norco dh bike prototype 6-bar linkage design drive side view
It is possible this dropout design could allow the team to play around with different rear-center lengths.

Bidding farewell to the linkage-driven single-pivot of the Aurum HSP, and the four-bar linkage of the Norco Range, the as-of-yet un-named prototype sees a 6-bar linkage design, wherein the main pivot is positioned high on the seat tube. Indeed, Norco is sticking with a high-pivot, seemingly very happy with the majority rearward axle path it delivers.

norco prototype downhill bike 6-bar linkage high pivot 22tooth idler pulley

It does of course mean that an idler pulley is required to route the chain close to that main pivot, dissociating conflicting forces from the drivetrain and suspension – i.e., reducing pedal kickback. On the prototype, an idler pulley positioned concentric to the pivot, is utilized – with 22 teeth, it is very large by current industry standards.

Only the Nicolai Nucleon 16 with the Lal Bikes Supre Drive runs an idler pulley this big, in a presumed bid to reduce friction.

On the Norco prototype’s linkage, we count seven pivots, if you include the one on the short yoke (dark blue) that is driving the shock. The shock is positioned very low in the frame, driven by that yoke that is itself driven by a link (orange) that will rotate counter-clockwise about the main pivot as the bike is pushed through its rear wheel travel.

norco prototype downhill bike 6-bar linkage layout pivot locations
Image annotated by Cory Benson – Bikerumor.

Connected to that link, about two thirds of the way up its length, is a bar (pink) that couples the movement of the lower linkage (blue) to the orange link. It moves through space as the lower linkage (which importantly is not articulating about a BB concentric pivot) extends away from the front triangle to extend the bike’s effective rear-center length as it is pushed through its travel. And, let’s not forget there is a pivot on the chainstay, as well.

norco prototype downhill bike 6-bar linkage flip-chip upper shock mount
A flip-chip at the upper shock mount will allow for some adjustment.

I shan’t be commenting on what kind of kinematic is likely to arise from such a layout, but it seems to work nicely with both air and coil shocks. Lucas Cruz just won the Canadian National Champs aboard this prototype Norco, sprung by a RockShox air shock running a very, very large air can – as compared to the modestly-sized air can we see on the Super Deluxe Ultimate Air Shocks, that is. Meanwhile, 2nd place Mark Wallace‘s bike was coil-sprung.

Also noteworthy is that a Norco Development Engineer involved in the creation of this bike, Kirk McDowall, filled third place on that same podium. Chapeau.

Unfortunately, Gracey Hemstreet suffered a suspected head injury, and did not complete a race run.

prototype norco downhill bike alloy frame 6-bar linkage spotted canadian national championships 2023
In one of the team videos, Gracey Hemstreet said, “It’s pretty insane how much better the new bike is”.

The snippets of information we’ve collated from the Norco Factory Team’s social media indicate that the team will be switching to this new bike for the rest of the Downhill World Series, kicking off in Pal Arinsal, Andorra, on the 24th August.

Back to that prototype RockShox Boxxer Blackbox DH fork for a quick second… We already spied it at Lenzerheide, but this good set of Norco photos gives us a more detailed look. We spy a new damper cap that doesn’t say Charger anymore and has both HSC & LSC marks on it. Plus, there’s a newly relieved upper crown, more lower crown machining, and both get forward-facing bolts.

Until then!

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