Colorado's trail width limits are 50 and 62 inches. A 64-inch UTV fits neither.

If you've shopped a sport side-by-side recently you've heard "64-inch trail width." Kawasaki's new KRX 1000 TR is built to it. Forum threads treat it as a Colorado thing.

We went and read the maps. Colorado's Motor Vehicle Use Maps — Pike-San Isabel, GMUG, San Juan, Rio Grande, White River — and BLM travel maps for Gunnison Gorge, Dominguez-Escalante, Grand Junction and Royal Gorge. Here's what's actually on them.

Almost everywhere: 50 inches

The Forest Service's standard MVUM legend has one width class for trails: "Trails open to vehicles 50 inches or less in width (ATV, motorcycle, etc.)." The next category up is "Trails open to all (full size) vehicles…"

Most Colorado forests use exactly that. The GMUG's travel rules say it without hedging: "UTVs greater than 50 inches in width are not allowed on Forest Service ATV trails." BLM is the same — the Flat Top–Peach Valley brochure for the Gunnison Gorge NCA: "All vehicles more than 50 inches in width must stay on main access roads and designated jeep routes." The state's COTREX app sorts wheeled motorized routes three ways: Motorcycle, ATV, and "OHV Riding (>50″)."

On those maps, if your machine is over 50 inches, you are a full-size vehicle. Jeep roads and full-size trails. Everything marked 50-and-under is closed to you.

The exception: 62 inches on the White River

The White River National Forest — Rifle, Blanco, Aspen-Sopris and Dillon districts — uses a 62-inch class on some of its OHV trails. Two examples straight from the Forest Service:

• Buford–New Castle Parallel OHV #2290, 14.5 miles, Rifle Ranger District: "open to motorized vehicles less than 62 inches in width."
• Windy Point Bypass #1846, 3 miles off Transfer Trail: "open to motorized vehicles 62 inches or less in width."

The Rifle district's 2026 map lists six of them — 1271, 1846, 2290, 2293, 2294 and 2804 — and they're seasonal, open May 21 to November 22 (June 21 for 2804). The map's own wording: "less than 62 inches in width at the widest point on the vehicle." Widest point. Mirrors and tires count.

COTREX tracks this too — route records carry an "Allows OHVs >62″" field, and 55 motorized routes in the state answer no: mostly White River districts, two BLM Colorado River Valley routes, and one trail on the San Juan's Dolores district.

It's the same 62-inch line the Black Hills National Forest uses in South Dakota, in the same Forest Service region.

Why 64 keeps showing up

Sixty-four inches is the width most sport UTVs are built to. It's a machine spec, not a trail class. Stay The Trail's permit chart defines a "Side by Side trail" as one with a maximum width of 64 inches, but no Colorado map we read uses that number — and Stay The Trail's own trail-signs page says over-50 machines ride full-size routes only. Nobody's pages agree with each other, which is the reason this post exists.

What it means when you're buying

On most Colorado maps, over 50 inches is full-size. A 63.8-inch KRX 1000 TR and a 68.1-inch KRX 1000 have the same access on the Pike-San Isabel, the GMUG and the San Juan. We couldn't find a single trail there that one can ride and the other can't.

On the White River's 62-inch trails, neither fits. 63.8 is over 62. Kawasaki's own page calls the TR's stance "64-in trail-ready." In Colorado, 64 doesn't unlock anything 68 doesn't.

If you want the 50-inch trails, you need a 50-inch machine. Polaris and Can-Am both build one. You give up power and cabin room to fit the gate.

Colorado has plenty of full-size riding — Red Cone is full-size, Rampart Range has full-size routes — so this isn't a warning off sport machines. It's a reason not to let a trail-width spec decide between them if Colorado is where you ride.

Measure what you own

Stay The Trail puts it plainly: "If you buy an ATV that is under 50″ in width but later add new wheels and tires that put it over 50″ in width, it can no longer be used on 50″ trails." Wheel spacers, offset wheels, wider tires — each one moves you across a line. If you're on a 50-inch machine and looking at wheels and tires, measure first. Not sure? Ask us before you order.

Read the tables, not just the legend

Here's the part that caught us out. On the Rifle district's 2026 MVUM, the 50-inch class is in the legend at the top of the sheet. The 62-inch class is in a table in the bottom-right corner titled "Seasonal and Special Designations – Trails." If you only read the legend, you'll conclude Colorado has one width line — which is what we concluded the first time, until we read the table. Download the whole PDF and read every table on it.

The table, from the 2026 Rifle Ranger District MVUM. US Forest Service, public domain.

Our owner runs Adrenaline Off-Road Park at PPIR and rides the same public trails you do. If you know a signed 64-inch trail anywhere in Colorado, send it — we'll update this.

Sources: USFS MVUM FAQ · 2026 Rifle RD MVUM (PDF) · Buford–New Castle Parallel OHV #2290 · Windy Point Bypass #1846 · GMUG OHV Travel Rules · BLM Flat Top–Peach Valley brochure, Gunnison Gorge NCA (BLM/CO/GI-13/010) · COTREX · Stay The Trail: Vehicle Width, Registration & Permits, Trail Signs · Black Hills NF MVUM FAQ · Kawasaki KRX 1000 TR and KRX 1000 spec pages