2021-2025 Yamaha Mountain Max 800 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 wait is over! Yamaha returns to the two-stroke mountain market in a big way with the Mountain Max 800, which is virtually identical to it's Arctic Cat M 8000 Alpha One cousin so the products we make and sell for the Cats are a direct fit for the Yamaha as well. The C-TEC2 794cc engine with Semi-Direct Injection (SDI) delivers increased performance and rideability in the 160-hp class. It provides crisp throttle response, outstanding mid-range and class-leading performance in addition to improved fuel mileage and reduced oil consumption.
You know we can't leave well enough alone though- we've developed many performance parts and accessories for the 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! We had many machines equipped with our Stage 2 Exterminator Kits out on the snow in the 2017-2018 season, and riders were raving about how they took the smooth running, yet hard pulling 8000 C-TEC2 to another level, with a fun factor above and beyond any other stock displacement, naturally aspirated machine whether it be a ZR trail blaster or a M-Series mountain masher. Those riding M 8000's equipped with our Supercharger Kit reported rock solid pull and go reliability, with power, consistency, and instant throttle response that simply can't be matched by other boosted machines. For 2019, Arctic Cat has made only minor tweaks to the drivetrain on the 8000 series machines, so you can expect the same great performance with our kits and components. The big news is in the suspension department with the ZR iACT models with electronically adjustable shocks, and the new Alpha One model that is truly a game changer in the steep and deep- just add a healthy dose of Straight-Up USA Horsepower to either of these platforms to make the best even better! The 2020-2021 models have changes to the top end and injection system, but the power output is virtually the same as 2018-2019 and our Exterminator Kits and Supercharger will give you the extra kick that will put a permanent grin on your face!
- Clutch Weight Bushing // TEAM Clutch - 2016-2021 Arctic Cat Snowmobile / Wildcat // P-22 Clutch - Polaris Snowmobile / UTV$15.95sku:RWB-2
New and Improved material as of April 2024!
These replacement weight bushings are for Speedwerx TEAM and P-22 clutch weights. Sold each.
Learn More - Clutch Weight Bushing // ADAPT Clutch - 2022+ Arctic Cat Snowmobile / Wildcat XX$15.95sku:RWB-ACW
These replacement weight bushings are for our ADAPT clutch weights. Sold each.
New and Improved material as of April 2024!
Learn More - Tee // Speedwerx 30th Anniversary // Dark Heather GraySpecial Price $15.00 Regular Price $20.00sku:SPXTS25-30TH
Get one of these new tees from Speedwerx and support your favorite brand!
Learn More - Tee // Speedwerx Rental Car Test Driver // CreamSpecial Price $15.00 Regular Price $20.00sku:SPXTS25-RCTD
Get one of these new tees from Speedwerx and support your favorite brand!
Learn More - Lightweight Chassis Spar Insert // 2012-2024 M / XF, 2012-2015 F / ZR Models$13.09sku:1607-747-M
Our Lightweight Chassis Spar Insert reduces weight by .75lbs when replacing all six stock inserts! SOLD EACH.
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- TEAM BOSS / ADAPT Driven Clutch Delrin Washers // 2016+ Arctic Cat Snowmobile / Wildcat XX$10.00sku:930651
The secondary spring has to rotate in the spider as the clutch shifts. You can greatly reduce the scrubbing friction of the spring with the Delrin washer kit. Sold in a pack of 3.
Learn More - Tee // Speedwerx Retro 44 // Heather GraySpecial Price $10.00 Regular Price $20.00sku:SPXTEE22-GR
Get one of these new tees from Speedwerx and support your favorite brand!
Learn More - Top Sprockets - Borg Warner Hyvo - 13 Wide - 19T Internal Spline - 2018+ M 6000/8000 / 2018-2019 XF 8000 HC / 2021+ Riot X 8000 or ZR 6000 R SX & XC$0.00sku:3602-XXX
These Genuine Arctic Cat OEM Borg Warner Hyvo Top Sprockets fit only 2018+ M 6000/8000 / 2018-2019 XF 8000 HC / 2021+ Riot X 8000, or 2018+ ZR 6000 R SX & XC with hollow jackshaft.
Learn More - Clutch Weight Thrust Washer // ADAPT Clutch - 2022+ Arctic Cat Snowmobile / Wildcat XX$8.99sku:1646-144-050
These thrust washers or shims for the ADAPT primary clutch are .050” (1.27mm) thick, or slightly more than the .043" (1.1mm) washers that come stock. SOLD EACH.
Learn More - Drive Belt Removal / Deflection Adjustment Tool // ADAPT, TEAM BOSS, & Tied Secondary$7.95sku:650343A must have for your tool box... Learn More
- Long Exhaust Spring - 2.6''$4.10sku:ATV-LSReplace your old, stretched-out exhaust springs... Learn More
- Short Exhaust Spring - 2''$4.10sku:ATV-SSReplace your old, stretched-out exhaust springs... Learn More
- Speedwerx Decals // Straight-Up USA Horsepower Logo$0.00sku:SPXDWe have decals in a variety of sizes for your Snowmobile, ATV, UTV, Trailer, Race Car, Beer Fridge, or just about anywhere else you want to stick 'em! Learn More
- Speedwerx Catalog$0.00sku:CATALOG
NOTE: With the cancellation of HayDays in 2020, we have elected not to print a 2021 Catalog and will likely not be printing any more going forward. Please take a look around the website as you will find all the latest updates and many more products new and old that are not listed in the print catalogs, plus technical information and product videos that you will only find on the website.
Learn MoreOut of stock - Primary Clutch Spider and Post Shims // Polaris P-85, Arctic Cat 6 Post and 9 Post, and TEAM Rapid Response Clutches$0.00sku:SPXCS
These shims will help you dial in your race setup or adjust your belt spacing. Various sizes available for Polaris P-85, Arctic Cat 6 Post and 9 Post, and TEAM Rapid Response clutches.
Learn More - Clutch Roller Bushing Kit // ADAPT Primary Clutch - 2022+ Arctic Cat Snowmobile / Wildcat XX$77.95sku:ACARB
Bushings SOLD OUT- pre-order now for projected shipment late Apr.
The Speedwerx Clutch Roller Bushings for the Arctic Cat ADAPT clutch are made from Torlon and are much more durable than the OEM bushing material. For your convenience, we have made a kit that includes the three replacement bushings and tools to assist in the removal and installation.
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