2025-2026 Arctic Cat ZR / RIOT / M 858 CATALYST Performance Products & Parts | Speedwerx Inc.
For tech info, dyno tests, and videos, check out the product pages below or click here- Technical Information & Videos
The CATALYST platform transformed the experience of mountain, trail and crossover riders alike in 2024. Now with the 858 engine, you can push the limits even further with bigger power in the industry's easiest to ride package. Compared to Arctic Cat's 794cc engine, the 858 provides 11% more power and torque - and in a package that's 4% lighter. New for 2026, models like the EXT Special and M 858 HCX and HCR continue to build on the lineup of machines that debuted to rave reviews in 2025. You know we can't leave well enough alone though- we will continue the development and expansion of our lineup of performance parts and accessories for these new models with the same quality, durability, and of course the Straight-Up USA Horsepower that has made us known as the Worldwide Leader in Arctic Cat Performance!
No need to call for product updates- just keep an eye on this page and our social media channels for announcements on new products. When they are released and available for purchase, you'll see them here first!
TECH NOTE: Power Valve cables- we have seen a large number of sleds that the power valves are not set properly from the factory or they have moved, this dramatically effects the overall performance of you machine. Using AC tool # 836-00005 you need to confirm these are set right and if you have issues check them again. In our opinion, this is needed on every single 858 out there even in bone stock form. There is also a Technical Advisory regarding the Servomotor Bracket Alignment issued 12/5/25- your dealer may have already contacted you about this done this as part of the pre-delivery inspection, but they can help you with these adjustments if you are not comfortable doing them yourself. You can purchase the Adjustment Tool Kit here- https://speedwerx.com/apv-adjustment-tool-kit-858-c-tec2-models.html
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Turbocharger Kit // 2025-2026 Arctic Cat M 858 C-TEC2$6,500.00sku:ACTK-858 -
Turbocharger Kit // 2025-2026 Arctic Cat ZR / RIOT 858 C-TEC2$6,500.00sku:ACTK-858-ZRTrail Turbo Kits are in the werx! We are safely seeing over 215 HP at 8300-8500 RPM with 5 psi of boost in summertime conditions! Stay tuned for more info...
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Stage 2 Exterminator Kit // 2025-2027 Arctic Cat CATALYST M 858 C-TEC2 Models$2,479.75sku:ACM858EXT-2The Speedwerx Stage 2 Exterminator Kit for the Arctic Cat CATALYST M 858 is the ultimate bolt-on performance package for pull and go reliability on pump gas!
Available now for M 858 High Elevation applications! Stay tuned for the Low Elevation kit release date later this season pending testing on the snow.
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Stage 2 Exterminator Kit // 2025-2027 Arctic Cat CATALYST ZR 858 / XF 858 / Riot 858 C-TEC2 Models$2,479.75sku:ACZR858EXT-2The Speedwerx Stage 2 Exterminator Kit for the Arctic Cat CATALYST ZR 858, XF 858, and Riot 858 is the ultimate bolt-on performance package for pull and go reliability on pump gas!
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Fat Daddy Single Pipe and Y-Pipe // 2025-2026 Arctic Cat ZR / RIOT / M 858 C-TEC2 // 0-5000' Elevation$979.95sku:AC858S-CCNow Available!
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Our Fat Daddy Single Pipe Kits are a must-have for maximum power and performance, and they're lighter than stock too! -
Fat Daddy Single Pipe and Y-Pipe // 2025-2026 Arctic Cat ZR / RIOT / M 858 C-TEC2 // 5000' + Elevation Only!$979.95sku:AC858S-2-CCOur Fat Daddy Single Pipe Kits are a must-have for maximum power and performance, and they're lighter than stock too!
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L2 Competition Series Lightweight Muffler // Titanium // // 2025-2026 Arctic Cat ZR/RIOT/M 858 C-TEC2 CATALYST Models$699.95sku:AC858M-2-TIOur L2 Series Titanium Muffler weighs only 2.2 lbs.- that's 16.35 lbs. lighter than the stock suitcase on the CATALYST 858 models!
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Hypershift Clutch Kit // 2025-2026 Arctic Cat CATALYST M 858 C-TEC2 Models$549.95sku:CKA858High Elevation Kits are available now! Low Elevation Kits are in the werx- stay tuned for the release date later this season pending testing on the snow.
The Speedwerx Hypershift Clutch Kit for the 2025 Arctic Cat M 858 was developed and tested by the same team of people that Factory Team Arctic Cat trusts and uses!
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Hypershift Clutch Kit // 2025-2026 Arctic Cat CATALYST ZR 858 - 1.25-1.35" Track$549.95sku:CKA858-1The Speedwerx Hypershift Clutch Kit for the Arctic Cat ZR 858 was developed and tested by the same team of people that Factory Team Arctic Cat trusts and uses!
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Hypershift Clutch Kit // 2025-2026 Arctic Cat CATALYST ZR 858 / Riot 858 - 1.5-1.75" Track$549.95sku:CKA858-2NEW RELEASE- Pre-Order now for projected shipment mid-April.
The Speedwerx Hypershift Clutch Kit for the Arctic Cat ZR and Riot 858 was developed and tested by the same team of people that Factory Team Arctic Cat trusts and uses!
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EZ LYNK Auto Agent 3 Diagnostic Scan Tool and Cables$549.00sku:100EE00AA3Get Connected with The World's Most Powerful Vehicle Scan Tool. EZ LYNK puts your technician in the front seat whenever and wherever you choose and is the vehicle interface for all EZ LYNK apps.
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Speedwerx ECU Tunes // 2025-2026 Arctic Cat ZR / RIOT / M 858 C-TEC2 Catalyst$449.95sku:ECU-858Stage 2 and 500' Stock Drag ECU Tunes are now available!
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Our ECU programs offer the most control to all of the hidden features in the stock ECU and allows us to produce the most power with the best throttle response and acceleration. -
Lightweight Muffler // Ceramic Coated // 2025-2026 Arctic Cat ZR/RIOT/M 858 C-TEC2 CATALYST Models$399.95sku:AC858M-CCOur Lightweight Muffler for the CATALYST 858 cuts 9.15 lbs. while maintaining a very trail-friendly sound level!
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L2 Competition Series Lightweight Muffler // Stainless Steel // // 2025-2026 Arctic Cat ZR/RIOT/M 858 C-TEC2 CATALYST Models$399.95sku:AC858M-2Our L2 Series Muffler is 14.1 lbs. lighter than the stock suitcase on the CATALYST 858 models!
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4th Wheel Kit - 7.12" Wheels // 2024-2026 Riot 600/858 146" / 2020-2026 Riot 6000/8000/9000 146" / 2019 Arctic Cat ZR 6000/8000/9000 129''$339.95sku:SPX4WK-6-7This 4th Wheel Kit utilizes four high quality rubber coated idler wheels for more stability and traction!
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4th Wheel Kit - 8" Wheels - Arctic Cat // 2024-2026 ZR 600/858 / 2019-2026 ZR 6000/7000/8000/9000 137'' / 2019 XF 6000/8000/9000$339.95sku:SPX4WK-6-8This 4th Wheel Kit utilizes four high quality rubber coated idler wheels for more stability and traction!
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Stealth Head Mod // 2025-2026 Arctic Cat ZR / RIOT / M 858 C-TEC2 Catalyst$129.95sku:ACFHM-858Our Stealth Head Mod with billet dome inserts is the key to unlock maximum power and performance from the 858 C-TEC2!
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Speedwerx Hypershift Dual Adjustable Clutch Weights // Arctic Cat ADAPT Clutch$212.70sku:ACWOur Hypershift Dual Adjustable weights for the Arctic Cat ADAPT Clutch will replace many sets of standard weights!
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Spider Removal Tool // Arctic Cat ADAPT Primary Clutch$199.95sku:APCSTThis tool is used for spider removal and reinstallation on the ADAPT primary clutches used on 2022 and newer Arctic Cat Snowmobiles and Wildcat XX models.
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0627-127 OEM Arctic Cat Drive Belt$199.95sku:0627-127We carry a full line of Arctic Cat stock drive belts. We have them on hand and ready to ship to you! Learn More -
Billet Aluminum Primary Clutch Cover // Arctic Cat ADAPT$189.95sku:BCC-ADAPTNon-858 covers SOLD OUT- Pre-Order now for projected shipment mid-April.
These covers are not just for looks! They do look sweet but we built them with a purpose on top of that. These covers are stronger than stock and have features that help reduce flexing and fatigue over time.
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Speedwerx Lightweight TEAM BOSS / ADAPT Helixes // Compound Cut$187.95sku:TBH-CCustom Cut 3 Roller Versions Now Available!
Our TEAM BOSS / ADAPT Helixes are machined in-house- we shave off excess material to save .10lbs over the stock helixes without compromising strength or durability.
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Speedwerx Lightweight TEAM BOSS / ADAPT Helixes // Straight Cut$187.95sku:TBH-SCustom Cut 3 Roller Versions Now Available!
Our TEAM BOSS / ADAPT Helixes are machined in-house- we shave off excess material to save .10lbs over the stock helixes without compromising strength or durability.
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Speedwerx Lightweight TEAM BOSS / ADAPT Helixes // Progressive Cut$187.95sku:TBH-PCustom Cut 3 Roller Versions Now Available!
Our TEAM BOSS / ADAPT Helixes are machined in-house- we shave off excess material to save .10lbs over the stock helixes without compromising strength or durability.
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High Flow Intake Kit // 2025-2026 Arctic Cat ZR / RIOT / M 858 C-TEC2$169.95sku:AC858-HFIOur High Flow Intake Kit is key to unlocking maximum power and performance on the 858- we are seeing a 5hp gain by opening up the restrictive stock plenum!
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