Melding trail capability and performance 

By the staff of Dirt Wheels

Yamaha’s Wolverine RMAX4 isn’t really aimed at sand dunes, but the Sand Hollow trails are separated by dunes in places. The RMAX4 was willing and able in the sand.


Compared to the Wolverine X4,  our 2021 Yamaha Wolverine RMAX4 Limited Edition has got a radical upgrade in power and suspension, so we are far more than satisfied. The smooth and effective X4 847cc engine we liked so much has been punched out to 999cc. Yamaha wanted the most power in the Sport/Rec class. That means facing off with the Polaris General, Honda Pioneer 1000 and others. It easily delivers with sport 1000-horsepower numbers, but with drivability that excels on serious trails. Yamaha’s Ultramatic CVT with built-in centrifugal clutch provides smooth hook-up and usable power transmission. The Ultramatic is easy on belt life, so Yamaha offers a 10-year belt warranty!

With the Ultramatic, the CVT belt is always engaged. A side benefit is that you have positive engine braking. Yamaha’s On-Command 4×4 system does not require that the rear wheels slip before you have power to the front wheels. Because of that, you always have four-wheel engine braking as well. That makes a big difference in technical driving. The On-Command system also provides a differential lock that we found handy for extreme obstacles.

Picking a line that minimizes the angled ledges you hit on stair-step climbs helps, but the differential lock and D-Mode in Crawl mode made it a breeze. This machine loves tech trails.

All Yamaha RMAX models have D-Mode capability. It comes stock on the RMAX4 LE that we tested and on the XT-R version. It is on the base models, but you need to buy the switch and plug it in.

D-Mode allows push-button control of power delivery. Choose between Sport, Trail and Crawl. D-Mode doesn’t cut any power; it allows 100-percent power in all modes. It merely changes how fast the EFI throttle plates open. The difference in the three modes are significant, and they make a huge difference in drivability while maneuvering technical sections.

We handled some truly impressive drops (and climbs) in the RMAX4. The positive engine braking with the Ultramatic CVT is a help here. The brakes engage smoothly as well.



The Wolverine track width was just under 60 inches, but our RMAX4 LE is a full 64 inches. Compared to the X4, the RMAX4 added just over 7 inches to the wheelbase. Front suspension travel jumped from 8.7 inches to 14.2 inches! In the rear, the travel stepped from 8.9 inches to 13.3 inches. That rear travel is actually reduced for the RMAX4. The RMAX2 has just over 16 inches of rear travel. Partially thanks to the travel and somewhat from the jump from 26-inch tires to 29-inch tires of the RMAX4, the ground clearance lifted from 10.7 inches to 13.4 inches.

The Fox iGS shocks allow the driver to select three damping settings via a switch on the dash. We used the settings a lot while we were driving, and they worked well.

Yamaha strengthened the chassis significantly in front and behind the cab area. In addition to more travel, the RMAX4 Luxury Edition (LE) is suspended with Fox iQS piggyback shocks. Fox iQS shocks have three levels of damping adjustment, like the Fox QS3 shocks on other RMAX models, but the damping can be adjusted on the fly via a dashboard switch. It isn’t smart suspension like the Polaris Dynamix, Can-Am Smartshox or the high-end Honda Talon 4, but it is very nice to have adjustments at your fingertips. Aiding the suspension and handling are front and rear sway bars.

This uniquely shaped passenger grab bar was developed using information from Yamaha’s watercraft division. It is comfortable and easily adjustable.

Unfortunately, the weight also jumped from 1,666 pounds for the X4 to 2,059 pounds for the RMAX4. Perhaps it is a good thing that Yamaha boosted the power and displacement?

When Yamaha selected a wider stance and greater travel for the RMAX4, it also beefed up the suspension components. Look under the hitch to see the thickness of the robust skid plate.



Our RMAX4 LE is the most luxurious of all the RMAX models. It is interesting that the actual seat specs and interior finish are not upgraded in any way you can see, but there is an unmistakable feeling of luxury the other trim levels do not have. The cab-entry opening is wider than the X4, and the shoulder bolster is smaller so it doesn’t obstruct the opening. Seat mounting is 13mm back from what the X4 had.

We are happy to see the pedals are angled down with a longer throttle face. That makes a big difference for taller drivers or those with limited ankle movement. Yamaha added molded soft touch-points on the doors and side of center console. Your knees will appreciate them after a long day on the trail.

Yamaha provides a high-traction dead pedal for the driver and passenger, and an angled foot rest for rear passengers. Given the sport bent of the RMAX4, the tilt-adjustable steering wheel has the YXZ shape, but it has a softer rubber over-molding for better feel. Yamaha opted for a parking brake instead of Park in the transmission.

The passenger grab-handle looks like a scared strongman bent it, but the shape is one that was exhaustively tested in the Yamaha watercraft division, and it works well. It adjusts in small increments with no pin to pull to make those changes. There is also an open-gate shifter. It is easy to see and feel when it is in gear.

Yamaha has done a great job getting four comfortable seats in a compact space while allowing room for people as well. The rear seats slide forward to handle cargo.



In the X4, the seat belts had two adjustment points to line it up with your shoulder, but now there are six positions on all four seat belts. LE and XT-R models have USB power ports. Our LE has the Yamaha Adventure Pro GPS, speakers and a built-in stereo. Rear speakers are pre-wired, but they are accessories. Even though it is built in, there are easy provisions to unlock the large-screen GPS and remove it from the car.

Adventure Pro gives Yamaha owners the opportunity to share their ride experiences. Adventure Pro comes with GPS mapping and navigation, online adventure planning, 115,000+ pre-loaded trails and waypoints, the Yamaha-exclusive Timing Mode, social sharing functionality, vehicle integration and customization, and more. There is an SD-card slot for loading GPX files. Add your trails or download them from Yamaha’s site. Timing mode lets you set a course and keep lap information. That is great for testing adjustments.

All in-cab switches are backlit, and there is a blue LED floor lighting. All switch settings are indicated at the switch and on the meter. Base models don’t have some features or backlighting, but are all pre-wired for them. Speaking of wiring, there are 11 switch knock-outs—10 on the LE since the standard winch already uses one. The little knock-out covers are the same as the floor-drain covers.

Under the hood are CVT and engine-air intakes. The oiled foam air cleaner and intake are upsized for the 1000. There is a back-up paper filter downstream to protect the engine. There are washer bottle mounts under the hood. Yamaha’s accessory glass windshield has a wiper motor and washer installed. The windshield is sold complete.

The RMAX is pre-wired for accessories. Simply buy the appropriate pigtail for a clean, water-resistant connection. Tires are a little confusing with the RMAX line. Some use the Maxxis Carnage, some the Maxxis Carnivore and others a Yamaha-developed GBC Dirt Commander. Our RMAX4 LE came with staggered (wider rear) Maxxis Carnage. Two-seat RMAX models have a “square” setup with all four tires the same size.

Note the almost automotive quality of the dash and controls, the prominent center location of the GPS and the unique shape to the passenger grab bar. This is one dialed-in cab area.



Yamaha chose to introduce the RMAX at Sand Hollow in Hurricane, Utah. It is a great test location with trails varying from ultra-slow tech crawling to fast whoop sections. There are even dunes. Right from the first ride, we appreciated the added comfort in the interior. Entering and exiting the car is easier and more natural. Our taller staffers could still stand more legroom, but there is enough. Our tall driver (6-foot-1) did fit comfortably in the rear seat as well. Visibility forward is great for technical driving. We began playing with the D-Mode drive setting immediately. Chosing  Sport for the dunes (no surprise), Trail for the trail sections and Crawl for the rock steps and ledges. We hit two obstacles that we employed differential lock for. Once we needed to shift into reverse to get diff-lock to disengage.

The 64-inch stance pleasantly aids stability on cambers while still allowing a nimble feel in tight sections. When we drove with 72-inch-wide cars, we found we could thread through areas they were forced to climb over.

Yamaha makes bold claims about the Yamaha Ultramatic CV transmission, and we have to say they are not exaggerating. We never had a hint of an issue with the belt. We even got to try the winch when we found another brand on its side in a giant crack in the rocks. It easily pulled the hapless machine out.

Whoops are not the best place for the RMAX4, but it does fine for a sporty trail machine. Ride quality is good, and the damping is controlled for accurate handling. During our driving we routinely selected different D-Mode settings, happily changed the iQS suspension settings on the fly, and even toggled between 4WD and 4WD with differential lock. We tried 2WD, but typically drive in 4WD.

The front A-arms are arched for maximum clearance. The standard winch is easy to use, and we put it to the test rescuing a tipped machine.



We ran the Wolverine RMAX4 LE through a wide range of trail conditions. A lot of use in Sand Hollow meant that the transition sand trails were very choppy. Despite that, the RMAX4 handled the chop well, and offered comfort crossing loose or solid rock. As stated, big whoops were not the best. The RMAX doesn’t get on top and skip across.

The new engine and transmission combo are ideally suited to trail work. It far outshines the 850 when you meet real deep sand or need power. We could not fault the brakes or steering. Yamaha made sure that the RMAX4 has a great turning radius like the X4. Almost all of the trails that we drove were quite challenging, with few areas for rest. In spite of that, the RMAX4 handled everything we hit in style. Even with the large rock steps, the ground clearance was fine.


Yamaha’s X4 was a smooth, polished machine, but for the rougher western U.S., the RMAX4 is a whole new level of fun, performance and competence. It will be a trail hit and a lot of competition for the other sport rec machines in the class.

Of all the Yamaha Wolverine RMAX models, the RMAX4 LE is the most feature-loaded. It has a luxurious look, electric-adjustable suspension and a high-performance engine.


Engine type Liquid-cooled twin four-stroke

Displacement 999cc Transmission Yamaha Ultramatic  V-belt with all-wheel engine braking; L, H, N, R

Final drive Shaft

Fuel system EFI

Fuel capacity 9.2 gal

Length/width/height 128.1”/66.0”/83.8”

Ground clearance 13.4”

Wheelbase 90.2”

Wet weight 2,059 lb.

Suspension/wheel travel:

  Front Independent double wishbone w/ anti-sway bar, Fox iQS piggyback shocks/14.2”

  Rear Independent double wishbone w/ anti-sway bar, Fox iQS piggyback shocks/ 13.3”


  Front 29×8-14 Maxxis Carnage

  Rear 29×10-14 Maxxis Carnage


  Front Dual hydraulic disc

  Rear Dual hydraulic disc

Bed capacity 600 lb.

Towing 2,000 lb

Colors Cobalt Metallic

Price $25,299

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Contact www.yamahamotorsports.com