THE CONTENDERS : ARCTIC CAT MOUNTAIN CAT
We ’ ll start with sled overviews , beginning with the new M 858 Mountain Cat Alpha One with ATAC .
The lightweight , second-year Catalyst chassis incorporates innovative features to accommodate diehard thrill seekers , allowing them to push their limits .
For 2025 , Cat took the good stuff from the 2024 Catalyst chassis M 600 lineup and added an 858cc mill built on an 85 mm bore x 75.6 mm stroke . This new mill features 8 percent more displacement than the 794cc C-TEC it replaces , but Cat says it charges through the snow with a whopping 11 percent increase in horsepower . The bottom of the case features built-in bosses to mount it low in the chassis .
Better yet , the new engine weighs 4 percent less than its predecessor while also optimizing the air intake by moving the reed cage 11 mm closer to the engine and featuring innovative exhaust valve control . A push / pull actuator provides infinite control over the sweep of the valve , which stays close to the piston at all times as opposed to a guillotine type which injects turbulent flow to the escaping exhaust . The port size can vary by 250 percent more than the prior design .
The new exhaust system is lighter and has more durable mounting methods . Power is delivered through ADAPT clutches to the final belt drive setup introduced on Catalysts last year . The HP then lights up a 15- by 165- by 3-inch PowerClaw track with a 3.5-inch pitch . The track wraps around the single-beam Alpha One rear suspension that ’ s damped through a 1.5-inch bore IFP center shock and Fox FLOAT3 iQSL in the rear , swinging 15 inches of travel . The rear of the short tunnel is capped by a tiny snowflap .
Up front , ProClimb G2 skis are spreadable between a 35- to 37-inch stance . They bolt to the revised and renamed AWS 36 front suspension . It shares a few components from prior years , but new spindles reduce drag in the snow . Fox FLOAT3 iQS shocks travel 7.6 inches .
Also new is the Garmin G8 display that can instantly show numerous operational specs , then navigate with built-in maps , switch through phone apps , and even use Group Ride Radio to communicate via text or cell to up to 20 other riders .
THE CONTENDERS : POLARIS PRO RMK
Next up , the Polaris 9R Pro RMK 165 returns for its third season in the same trim , but it wasn ’ t unchanged for 2025 .
Dubbed a factory mod powerplant , the 900cc Patriot 9R engine was designed for lightning-fast response to provide quick agility with effortless control to whichever machine it adorns . Cleanfire injection fuels the 88- by 74-mm bore and stroke , churning power through three-stage variable exhaust . The P-22 TEAM LWT clutch harnesses power to drive the QuickDrive2 belt system .
The demo we were able to procure spun a Series 8 2.75 track , aptly with 2.75-inch lugs . A 15- by 165- by 3.25-inch Series 9 track is the other option .
A Pro RMK rear skid travels 16 inches and sports Walker Evans Racing Light shocks , while the similar Walker Light
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