Colorado’s suspension upgrade & tuning specialists Push Industries are porting the same shim-less compression valve tech from their own ElevenSix shock over to RockShox forks with a new HC97 Charger damper. The new HC97 compression cartridge upgrade replaces the stock compression internals in recent Pike, Lyrik & Boxxer forks to deliver improved small bump sensitivity & grip, together with much more tunability…

Push HC97 Charger shim-less compression valve damper

Push HC97 RockShox Charger shim-less compression valve damper upgrade cartridge

courtesy PUSH

The trick to Push’s new RockShox Charger 2 & 2.1 damper upgrade is the internal replacement of conventional compression shim stacks with Push’s more sensitive & linear Shim-less Compression Valve. Besides claims of better traction and small bump sensitivity with more stability & control, the HC97 assembly also offers additional external fine-tuning via more clicks with a wider range of noticeable change.

The new Push HC97 cartridge is entirely manufactured and hand-assembled in-house in Loveland, CO. Similar to their Fox fork upgrade kit, it’s a direct replacement for the stock Charger compression assembly found in recent 35mm stanchion RockShox all-mountain, enduro & DH forks.

Push HC97 RockShox Charger shim-less compression valve damper upgrade cartridge

Here’s Push’s explanation of the mechanics behind the harshness of normal shims, and why their design delivers a better ride:

“With traditional shimmed compression valves, steel shims are bent upwards as fluid flows through the valve. The more aggressive the impact, the more these shims need to bend in order to allow the wheel to move through its travel. This shim bending is progressive in nature resulting in an increase in damping force leading to harshness on square edge impacts. Removing valving shims to help reduce harshness at high speeds leads to an overall reduction in compression damping and results in a decrease in low and mid speed control and performance.

The exclusive PUSH “Shim-Less” Compression Valve design, borrowed from the class-leading ELEVENSIX rear shock, eliminates this compromise. The progressive nature of shim bending is replaced by using a precision machined sliding valve seat that can “dump” fluid under the most aggressive square edge bumps. This resulting fluid flow allows the wheel to compress more freely in aggressive terrain resulting in more comfort and control through every stage of the fork travel.”

Push says a lot of what makes their upgrades improve overall performance is better synchronization of the all the possible internal systems in the damper. The custom tuning in mountain bike shocks & forks is seemingly endless & totally complex: low & high-speed compression, low & high-speed rebound, mid valves, shims, bleed ports, needles, bladders, and whatnot offering adjustability.

Push HC97 RockShox Charger shim-less compression valve damper upgrade cartridge

So Push focused on improving the internal communication between all these separate elements as they interact every time you hit a bump. The result is less delay in any individual system, making the HC97 perform better for everything from bump sensitivity to cornering traction.

Push is known for delivering more usable rider adjustment range in their suspension components, and the HC97 delivers on that too. 28 low-speed compression clicks give noticeable adjustment control based on the same parabolic low-speed needle design developed on their ElevenSix shock. Then, high-speed gets its own 28 clicks for changes to the damping curve you can really feel.

Push HC97 RockShox Charger shim-less compression valve damper upgrade cartridge

Rounding out their ‘Factory Tuning System’ approach, the HC97 compression damper kit also includes rebound valving shims along with a DIY guide to help you get the most out of your updated RockShox fork. Retail is $245 and they’re available globally to replace the Charger 2 & 2.1 dampers in recent Pike, Lyrik & Boxxer forks.

Push Ultra Low Friction (ULF) fork seal kits

Push HC97 RockShox Charger shim-less compression valve damper upgrade cartridgePush also offers their own separate Ultra Low Friction (ULF) fork seals. They’re made in 3D machined & polished molds to finish the complete fork overhaul.

Push HC97 RockShox Charger shim-less compression valve damper upgrade cartridge

At $38 for the set, Push ULF fork seals feature an exclusive dual lip scraper design that promises improved durability over factory seals. Also, Push’s seals contain higher levels of Molybdenum for another claimed boost in small bump sensitivity.

So, what happens if you upgrade with all this? Push says it “makes you faster than your friends who don’t have it!

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3 years ago

still a lockout like rct3 offers?

3 years ago

This is certainly a heck of a lot better than ring shims and poppet valves. I am curious why they didnt make this a cone valve. I certainly like the parabolic needles, quality engineering. Yes please.