Ryan Nitzen | March 24, 2024
The line between fun-loving weekend warriors and serious racers becomes harder to decipher with every passing model year. Sure, there are die-hards on either side of that spectrum, but many motorcycle owners dabble in racing and recreation. This gives manufacturers a tough job of offering machines that can do both in specialized ways. Do you buy the purpose-built motocross bike and make it off-road-friendly with many compromises? Or do you buy the off-road-oriented model and soup it up for racing? Yamaha’s updated YZ450FX is its answer to limiting compromise from track to off-road course and offering the best of both worlds.
Photography by Ryan Nitzen
What It’s Not | 2024 Yamaha YZ450FX Review
Let’s clarify one thing: the 450FX is not a trail bike. That’s what the Yamaha WR450F and family-friendly TT-R lineup is for. The FX is an off-road racing machine, period, and a very aggressive one at that. At its core, it is a fire-breathing motocross bike that has been tweaked for high-performance “closed-course” off-road racing.
For 2024, the YZ450FX enters a new generation as it follows in the footsteps of its fully redone YZ450F cousin, which was heavily updated a year ago. Now it’s the FX’s turn to get those updates. The latest FX has a heavily reworked aluminum bilateral beam frame, an all-new engine (that yields 500 rpm more over-rev), slimmer bodywork, and several other highlights, just like the F model got a year ago. But the FX receives more than just an “X” sticker. To be off-road competitive right off the showroom floor, Yamaha again outfitted the 450FX with several well-thought-out modifications specifically for off-roading. Compared to the motocrosser, the FX has an 18-inch (versus 19-inch) rear wheel, an O-ring chain, a composite skid plate, a folding aluminum kickstand, a nearly half-inch lower seat height, and a half-gallon larger fuel tank (2.1 gallons vs. 1.6 gallons) with a reserve light. Pair all that with other off-road-specific mods—such as off-road-friendly ECU mapping and suspension settings, a lower seat height, YZ450FX-specific engine mounts, and a unique five-speed wide-ratio gearbox—and you’ll see that Yamaha did its homework catering to the off-road racer.
The 2024 Yamaha YZ490FX got all the updates that its YZ450F cousin got last year.
The FX is fitted with a fully adjustable KYB suspension, which includes Yamaha’s highly touted Speed Sensitive System (SSS) coil spring fork, which now has a hand-operated compression clicker.
For all those additional parts, the FX has a $200 higher price tag than the YZ450F, which is a bargain compared to if you were to buy all those parts yourself and bolt them onto your YZ450F.
The YZ450FX has plenty of company, like KTM’s 450 XC-F, Honda’s CRF450RX, Husqvarna’s 450 FX, GasGas’ EX 450F, Sherco’s SE-F 450, Beta’s 430 and 480 RR, Kawasaki’s KX450X and several other big-bore four-stroke variants.
Like most of these bikes, the FX is explicitly designed for GNCC, NGPC, WORCS, Hare Scrambles, Hare & Hound (desert) and Sprint Enduro-type racing. The FX fits the bill if the course is semi-fast and the trees aren’t too tight. Top National Enduro pilots and ambitiously talented amateurs can wrestle a 450FX through the trees, too, but for us mere mortals, these bikes are best suited for faster, more flowing circuits.
The YZ450FX is a lot of motorcycle for tight woods racing, but when things open up, go ahead, grab a handful and hold on. The FX moves!
Hitting the Trails | 2024 Yamaha YZ450FX Review
So, what’s the new YZ450FX like to ride? Yamaha gave us the chance to test it in some real-life off-road conditions at its testing grounds in Union, South Carolina, just a few minutes up the road from where the Big Buck GNCC is held and not far from Randy Hawkins’ AmPro race headquarters. It’s also the same facility that just hosted round one of the U.S. Sprint Enduro Championship, and the knobby tracks were still nicely burned in. Mud, ruts, roots and a motocross track gave us just about every condition you could think of to put the FX through its paces.
The FX looks and, not surprisingly, feels like Yamaha’s YZ450F motocross bike. The new-gen chassis is ultra-slim and makes the rider’s cockpit feel narrow for easy movements to the front and back of the bike. The pegs-bar-and-seat ratio are all spot-on, just like its motocross cousin. Another way the FX keeps its slim character is the placement of the “oversized” tank. With the airbox still at the front of the bike, the tank fills in some “dead space” underneath the seat and down by the rear shock. Yamaha hit a double whammy on this design by saving space up top and keeping the weight of the fuel down near the bike’s center of gravity. The fuel light is another real-world addition, giving you a heads-up on when to return to the pits (we tested this!).
Yamaha didn’t let any open space go to waste to increase fuel capacity.
Riding a 450 in the woods is not for the faint of heart, and our West Coast test riders were undoubtedly reminded of this during our trip back East. Arm pump was real as we worked the blue beast through the wet conditions, which explains why several top GNCC XC1 riders opted for the smaller-displacement 350cc machines, at least the Austrian ones. With the FX’s powerful new engine and claimed wet weight of 251 pounds, the Yamaha 450FX is one of the most powerful bikes in its class and is a lot of motorcycle to hold onto in the tight stuff. However, the FX was spectacular on the moto track and through the flowy South Carolina trees. Without question, it will also be as impressive, if not more, on the wide-open GP tracks that litter the West Coast. Why? Because the new motor rips. We rarely got it out of third gear in SC. Low-end torque is immediate, and the transition from bottom to mid is smooth. Once you’re out of first gear, you rarely go back. Second and third gear is where all the fun is, and this is where we spent most of our time—in that area between low-end grunt and lower-midrange power—as we tip-toed through the woods. We opened it up on steep climbs and fire roads to see what this bike has under the hood. Mid-to-top is just as strong as we had imagined, and where it proudly displays its race-inspired DNA as you pick up the pace. With the bumped-up rev-limiter, the rpm and power continue to deliver as the speeds climb.
Unfortunately, the YZ450FX is not immune to the dreaded big-bore four-stroke flameout, which tends to happen when rpm is too low while in too high a gear. Some bikes are more susceptible to flameouts than others and we experienced a fair share with the FX.
Like the YZ450F, the FX is slimmer between your legs.
After riding the YZ450FX out of the box for a while, we wanted to see if we could “mellow” out the power a bit to make it a little easier to ride, and we hoped it would also reduce flameouts, so we hit up the Yamaha techs for some tuning advice via Yamaha’s smartphone Power Tuner app. They suggested adding fuel and advancing the ignition timing, which indeed toned things down a bit. We wanted more, though, so we ramped up the traction-control setting in the app, which also made a noticeable difference for the better. We continued fiddling around with the Power Tuner app, a convenient piece of equipment, for the rest of the day.
The FX retains its “light on” or “light off” handlebar switchgear, which allows the rider to toggle between two totally different pre-programmed engine maps. For example, suppose you’re racing a three-hour GNCC race: In that case, you can choose the aggressive map (light off), holeshot-pulling character for the first hour, and then bail out into a more mellow map setting (light on) when you get tired and/or when traction is scarce. Pretty cool.
The engine (and aluminum frame) is all-new. It now gives you 500 rpm more over-rev and still plenty of torque.
The FX has top-notch handling. Its new chassis is already a sharpshooter on the F, and we knew it would be good for the tight stuff. The updates to the frame improve agility in the corners, which also translates into ease of use when slicing through the trees. The nearly half-inch lower seat height (compared to the YZ450F) makes the FX a little more comfortable and easier to maneuver, and the frame offers excellent feedback, which Yamaha says is partly due to the built-in flex characteristic from the specially designed engine hangers. You can also adjust the positioning of the rubber-mounted handlebar to suit your comfort needs further.
It’s hard to beat the FX’s suspension.
New finger adjusters on the fork caps allow for easy trailside tuning, which we took advantage of by opening the compression two clicks. This softened the fork and let the front-end engage more in the slow-speed sections while giving the front tire more traction. The bike was responsive, and small inputs through the footpegs produced significant changes in direction when picking lines. This is crucial when racing through the trees and something the FX does noticeably well. CN
CN’s Jesse Ziegler grabs a handful on the new YZ450FX during the Big Buck GNCC in South Carolina. PHOTO: James Lissimore / Lissimore Photo
Welcome To The Real World:
Racing the 2024 Yamaha YZ450FX
It wasn’t a coincidence that Yamaha invited us to ride the new YZ450FX in South Carolina just a few days before the Big Buck GNCC. I will never turn down the opportunity to race a GNCC. I stumbled upon the chance during my first year as a motojournalist in 2005, and I’ve been hooked ever since. I’ve lined up for the flag wave 10 times, at least. And I’m coming back again every time I have the chance.
GNCC racing isn’t easy. It’s aggressive, tiring and intimidating, with its dead-engine start and hundreds of racers on the course simultaneously. But the atmosphere is like a big, warm, off-road industry hug—plus, you can pretty much find a beer anywhere you look. After my morning race, I can watch the pros do it. And they have pit stops! Also, there are food vendors with hibachi burritos and funnel cake.
I’ve raced two GNCCs on Yamahas before. Both were in Florida, once on a YZ250 and once on a WR450F, and both were great rides. This time on the YZ450FX was even better. I still struggled with the same old things, like being massively unprepared physically and not knowing what class to enter, but that didn’t stop me from laughing for a long two-hour morning race in the 45+ A class. I botched the start with a quick ignition and immediate flameout about 10 feet down the course. Then, I regrouped and figured I’d pick some guys off in the trees for the first lap, but that didn’t happen. I literally went backward the entire day, finishing 17th out of 24 in my class. It seems strange that I tremendously enjoyed a race where I was getting passed all day, but I’d go do it again right now. Because I did pass some people and felt the burn and beatdown of a motorcycle race. That’s worth it. I even had a late-race battle with fellow motojournalist Allan Brown from Dirt Rider, which was completely awesome. And that makes me feel like a winner.
The Big Buck GNCC course is a nice mix of an open-terrain (for woods riding) racecourse and a few technical roots to keep your attention. A lot of square-edge chop forms during the day, and the holes and bumps are not minor. The soil conditions were prime. There was not a speck of dust or mud, and I barely needed to pull a tear-off all day (I still pulled them all at once, though).
If anyone tells you the YZ450FX needs more power, that person is lying. PHOTO: James Lissimore / Lissimore Photo
I had my favorite Yamaha guys drop the fuel and ignition maps down as mellow as possible and crank the traction control all the way up. And the bike was still a wild pony. It became tractable once the rpm was in the lower midrange, but right off idle or at the crack of the throttle, this bike rips. I had arm pump for the entire first lap and did four laps in the race. So, once I could feel my fingers, I tried to calm down and let the bike do the work. Work it did, and I was basically along for the ride.
Motor strength aside, the best attribute of the new YZ450FX platform is its chassis. It’s easy to manipulate with small efforts and doesn’t feel like an old, heavy, angry 450 (okay, it’s still angry). I used the finger adjusters on the fork compression a few times on the course to tinker with comfort settings. Since I ignored the gas stop (maybe hoping to run out and enjoy a course-side beer with a spectator), I fully utilized the low-fuel light for about three-quarters of a lap. We learned the 2024 Yamaha YZ450FX can go 2:16:50.378 on one tank of fuel. Barely.
So, was the YZ450FX the perfect bike for me or for those like me to race a GNCC on? No. It’s a lot of motorcycle, but I can see its potential in the hands of someone like AmPro Yamaha’s Ricky Russell. But, unfortunately, I’m just Jesse Ziegler and I’m holding it back a lot. The YZ450FX has way more potential than me. So, here’s to racing a West Coast event on this beast soon, where you can open this thing up and let it fly, which I’m looking forward to doing on it and something I expect it will do well. And here’s to a new (maybe) YZ250FX bike intro at a GNCC next year!
I’ll buy the funnel cake. ~Jesse Ziegler
VIDEO | 2024 Yamaha YZ250X First Ride
2024 Yamaha YZ450FX Specifications
| MSRP: |
$10,199 |
| Engine Type |
4-stroke, single-cylinder |
| Valvetrain: |
DOHC, 4 valves (titanium) |
| Displacement |
450cc |
| Cooling system: |
Liquid |
| Bore x Stroke |
97.0 x 60.9mm |
| Starting System |
Electric |
| Fueling |
Mikuni fuel injection, 44mm |
| Transmission |
5-speed; multiplate wet clutch |
| Frame |
Aluminum |
| Front Suspension |
KYB spring, fully adjustable |
| Rear Suspension |
KYB single shock, fully adjustable |
| Front-Wheel Travel |
11.8 in. |
| Rear-Wheel Travel |
12.0 in. |
| Front Wheel |
21 in. |
| Rear Wheel |
18 in. |
| Front Tire |
80/100-21 Dunlop Geomax MX33F |
| Rear Tire |
120/90-18 Dunlop Geomax MX33 |
| Front Brake |
Hydraulic 270mm |
| Rear Brake |
Single 240mm |
| Rake |
27° |
| Seat Height |
37.6 in. |
| Ground Clearance |
13 in. |
| Fuel Capacity |
2.1 gal. |
| Weight (wet, claimed) |
251 lbs. |
