Shopping the Arctic Cat 858 Mountain and want to know how it really compares to the Ski-Doo Summit X 850 E-TEC, Polaris RMK Khaos 850 and Ski-Doo Freeride 850? Here’s an honest, sourced side-by-side — specs, horsepower, price and the places the competition wins — from Empire Cycle & Powersports in Spokane Valley, WA. The biggest engine in the 850 class — an 858cc two-stroke twin on the light new Catalyst chassis, with the acclaimed Alpha One single-beam rear suspension. Here’s the honest look against the mountain-sled benchmarks.
2026 Arctic Cat 858 Mountain vs. the mountain snowmobiles
The biggest engine in the 850 class — an 858cc two-stroke twin on the light new Catalyst chassis, with the acclaimed Alpha One single-beam rear suspension. Here’s the honest look against the mountain-sled benchmarks.
Arctic Cat858 Mountain Our pick | Ski-DooSummit X 850 E-TEC | PolarisRMK Khaos 850 | Ski-DooFreeride 850 | |
|---|---|---|---|---|
| Engine | 858cc twin | 849cc twin | 840cc twin | 849cc twin |
| Power approx. | ~180 hp* | ~165 hp | ~165 hp | ~165 hp |
| Mountain rear suspension | Alpha One single-beam | tMotion | React | tMotion |
| Chassis | Catalyst (light) | REV Gen5 | Matryx Slash | REV Gen5 |
| Track options | 154″ / 165″ | 154″/165″ | 155″/165″ | 146″/154″ |
| Price starting MSRP | from ~$16,999 | ~$16,949 | ~$16,799 | ~$16,499 |
Why buy the 858 Mountain from Empire
The biggest engine in the class and the mountain skid riders rave about — the underdog that genuinely competes.
- ✓Biggest engine in the 850 class. At 858cc, the in-house two-stroke twin is the largest of the 850-class mountain sleds — Arctic Cat cites an 11% output gain over the previous 800, with strong low-end for deep-snow pulls.
- ✓The acclaimed Alpha One rear. The single-beam Alpha One rear suspension is a favorite among mountain riders for effortless sidehilling and predictable, tippy-in handling — a genuine advantage in the steep and deep.
- ✓Light new Catalyst chassis. The Catalyst platform is lighter and more centered, with track lengths from 154″ to 165″ and hillclimb-focused HCR builds available — set up for real mountain terrain, and Empire is your local support.
- ●Straight talk. Be honest: the Ski-Doo Summit and Polaris RMK dominate the mountain market — far bigger followings, dealer networks and aftermarket, and both are proven 165-hp benchmarks. Arctic Cat is the underdog, and it doesn’t publish an official horsepower number. But the 858’s displacement, the Alpha One skid and the new Catalyst chassis make it a genuine contender, often at a competitive price.
And the price is the price. Our advertised number already includes freight, setup and our documentation fee — only sales tax and title/registration are added.
Watch before you buy — top Arctic Cat 858 videos
▶Arctic Cat M 858 — Tested and ReviewedIndependent YouTube review
▶2026 Arctic Cat HCR 858 — First Ride ReviewIndependent YouTube review
▶2026 HCR 858 — Full In-DepthIndependent YouTube review
▶I Bought the 858 Arctic CatIndependent YouTube review
Frequently asked questions
Is the Arctic Cat 858 Mountain a good choice?
The biggest engine in the class and the mountain skid riders rave about — the underdog that genuinely competes. At 858cc, the in-house two-stroke twin is the largest of the 850-class mountain sleds — Arctic Cat cites an 11% output gain over the previous 800, with strong low-end for deep-snow pulls.
How does the Arctic Cat 858 Mountain compare to the competition?
Be honest: the Ski-Doo Summit and Polaris RMK dominate the mountain market — far bigger followings, dealer networks and aftermarket, and both are proven 165-hp benchmarks. Arctic Cat is the underdog, and it doesn’t publish an official horsepower number. But the 858’s displacement, the Alpha One skid and the new Catalyst chassis make it a genuine contender, often at a competitive price.
Where can I see the Arctic Cat 858 Mountain near Spokane?
Empire Cycle & Powersports in Spokane Valley, WA stocks the Arctic Cat 858 Mountain with Up Front Pricing — freight, setup and our documentation fee are already in the advertised price. Text us at 509-498-3541 or browse the inventory online.
Figures are 2026 model-year from manufacturer and published sources; competitor specs and prices are approximate, vary by trim and market, and should be verified before purchase. MSRPs exclude tax and title/registration. Video links are independent third-party YouTube reviews for research; Empire Cycle & Powersports is not affiliated with the creators. Comparison by Empire Cycle & Powersports, Spokane Valley, WA.
Keep exploring
New to the category? Read our buying guides, see how Up Front Research works, or browse the inventory. Prefer to talk it through? Text us at 509-498-3541.
Reviewed & updated by the team at Empire Cycle & Powersports, Spokane Valley.