2019 Factory Off-Road Bikes—Slam Life Racing Honda’s CRF450X

Mark Samuels’ and Justin Morgan’s Baja 500-winning motorcycle.

Honda CRF450X on the beach.
The previous generation CRF450X enjoyed a long run with 13 years of development to make it the premier desert racing machine, but SLR Honda’s exceeded that performance level in months with lots of testing and some carefully chosen modifications to the new ’X.Mark Kariya

Desert racing exacts a toll on man and machine alike with its physical pounding, higher speeds, and longer duration. So when Honda introduced a genuinely new replacement for its venerable CRF450X (introduced in, what, 2005?), that replacement had big shoes to fill.

You see, despite being what some considered a heavy, softly suspended machine compared to the CRF450R motocrosser from which it was derived, that old ’X actually was the base for building an excellent desert racer with a few modifications.

In fact, the old CRF450X became one of the most successful desert bikes ever, winning literally dozens of times in various SCORE Baja races as well as amassing a few AMA Hare & Hound National Championship titles. In just the Baja 500, the old ’X owns 10 overall motorcycle victories.

Thus, the newest iteration CRF450X with its six-speed transmission, fuel injection, new frame, etc. had a lot to live up to when Slam Life Racing (SLR) Honda got a few early this year to begin development work.

As American Honda’s de facto reps in races south of the border, SLR owner Mark Samuels knew he had to give it a good initial outing and, along with Justin Morgan, did just that, winning the SCORE San Felipe 250 in April.

Honda CRF450X Moto Seat, IMS tank, Scotts steering stabilizer, Mika handlebar, and Acerbis hand guards.
Riders have a comfortable workspace with Moto Seat, IMS tank with sufficient capacity as well as quick-fill capability, Scotts steering stabilizer, Mika handlebar, and Acerbis hand guards.Mark Kariya

Between then and the 51st SCORE Baja 500 last weekend where we caught up with Morgan after finishing some pre-running a couple of days before the race, the SLR team refined the CRF450X even more.

As a result, the team is more confident than ever that the new ’X surpasses ol’ reliable and has the potential to grow even more. It starts, of course, with a bike just like the ones down at your local dealer, providing a good base upon which to build. “It’s really a solid package with a lot of OEM parts [on our bike],” Morgan says. “It’s just put together [carefully]. They come stock really nice, but we’ve taken everything and messed with it and tried different things. We’ve had a lot of test days out in the desert. It’s been a long road so far.”

And it’s been one they’ve traversed in a compressed time frame. Although the new ’X is closely related to the CRF450R and ’RX, it’s not as nervous at speed as you might expect, Morgan noting, “Surprisingly, they’re very stable, and the transmission is really nice out in the desert.

“The old bike has more of an old-style feel to it—I don’t really know how to put that other than we had 13 years of development into it, so it was really stable and really easy to ride with the carburetor and power delivery. The new bikes, yeah, they’re a little more aggressive; they have more gears—you’re shifting a little bit more. They’ve got that EFI feel to them, definitely—a little more aggressive, but the courses are getting rougher and it’s kind of a progression, a good progression.

“It kind of caught me off guard with this. It took a little learning on how to ride it. I definitely have to shift more and [the ratios] are pretty close together, it feels like. Sixth is pretty high though. We run a lot lower gearing [than the old bike]; we were running a 15/47 and now we’re running a 13/50, and we’re getting really good top speed out of them. You’re more busy [shifting]; I’ll even grab two gears going into a corner sometimes. We’ve done some testing with different [engine] configurations and I think the fastest on the dirt we’ve had is 109.”

Honda CRF450X front on the beach.
It starts with some of the best suspension money can buy—in this case high-end Showa A-kit components front and back. A surprising number of items (like the wheels, brakes, radiators, and skid plate, for example) are OEM however. Little details like the lower (stock) triple clamp that’s been cleaned of casting marks reflect the care that went into this build.Mark Kariya

Morgan insists the fuel injection makes the new ’X feel more like a motocrosser, but they’ve toned it down somewhat since they began the evolution: “The Mint [400] bike compared to this bike, this is a more Baja-friendly bike. It gets better traction and everything like that. It’s a little mapping and a little bike setup, a lot to do with the suspension has limited wheelspin. The pre-runner compared to this bike, [this] feels like it tracks better with how the suspension’s set up [and] the chassis is nice and soft-feeling.”

A major part of that is the upgraded suspension from Showa. “This is really good, high-end A-kit stuff and it’s amazing,” he notes. “It’s got bigger components. It’s got the good [Kashima] coating [on both the shock shaft and fork sliders], and it works better than it looks. It’s been a huge step. It’s actually a lot safer, too, I think.

“Definitely, our racebike is set up a little stiffer [than stock] and geared more toward riding at 95 to 100 percent across the desert. All our pre-runners are softer and a little more mellow to save our bodies all week. To be honest with you, I don’t know the spring rate in these forks because we’ve been playing with a lot of stuff—it’s Mark’s department more. It’s got more damping and [control], but the stock suspension isn’t bad at all. We can go really fast on the stock stuff, but this is that much better; it makes things a little easier.”

While it can be difficult coming up with a compromise setting acceptable to all riders on any team, SLR’s three (Justin Jones was nursing a knee injury and unable to ride the 500) are close enough in size and weight that it’s not a big deal. “I think we’re all about two millimeters different on the sag [setting],” Morgan muses. “We’ve gotten used to it. This bike’s actually sitting a little lower in the rear than we run the stock stuff, just a couple millimeters. We’re all three not too picky; we all kind of like the same settings.”

STI Tires provides its Tech II Pro tires to the team, and Nitro Mousse foam inserts eliminate the potential for flat tires. SLR is currently working to develop a Baja-specific tire combination utilizing different sizes as well as construction. Per SCORE rules, the spokes are safety-wired, but otherwise the wheels are stock Honda including the brake pads, rotors, and calipers. However, a CRF450R/RX unit replaces the stock master cylinder, mostly because the ’R/RX item doesn’t carry a mirror mount hole as the standard ’X/L does.

A full Pro Circuit system replaces the stock exhaust, though the T6 muffler isn’t a production item. “Pro Circuit built us a new pipe for [the Baja] 500,” Morgan shares. “We had one for the 250 and they were getting hot on the side and the packing was going away, so we’re getting more of a Baja-specific pipe. We’re really thankful for that.”

Honda CRF450X port job by San Diego Powerhouse.
A careful port job by San Diego Powerhouse in conjunction with trying different ignition maps results in power delivery that’s a bit mellower than stock so it’s more tractable but still aggressive enough for the rougher courses that hundreds of pre-run trucks help create.Mark Kariya

The head gets a port job from San Diego Powerhouse, a Hinson clutch helping transfer power to the rest of the drive train with its Mika Metals sprockets via D.I.D O-ring chain.

In the rider compartment, one finds a Moto Seat (stock height) behind one of IMS’ large-capacity tanks with quick-fill receiver covered by a tethered Modified Machineworks cap. A Mika Metals handlebar (the bend is similar to Renthal’s 996, though Morgan wasn’t certain) with A’ME grips and Works Connection perches for the OEM levers protected by Acerbis hand guards sits atop a BRP upper triple clamp, a Scotts steering stabilizer helping to keep things from getting out of hand.

IMS Core pegs replace the stock units, but SLR depends on the OEM polymer skid plate to protect the engine. (Honda’s Baja teams going as far back as the late Bruce Ogilvie days retained stock skid plates, deeming metal ones introduced unwanted rigidity to the chassis, reflected engine noise at the rider, and didn’t glide over rocks as well as plastic.)

Honda CRF450X muffler packing.
The muffler packing on one side began disintegrating prematurely at the San Felipe 250, so Pro Circuit built a Baja-specific unit for the 500. While some will complain there’s no longer tool-less access to the air filter, Morgan insists that the improved airbox design makes filter removal/replacement equally quick.Mark Kariya

Although the radiators remain OEM, the addition of wire mesh adds a bit of protection from cactus, small sticks, and other objects. In addition, Morgan insists they don’t really miss the no-tools-required air filter access of the old model as the new ’X has an improved airbox that makes air filter removal/replacement very quick—just use a battery-powered tool to remove the two seat bolts.

While the team employed the standard CRF450X kill switch at San Felipe, for the 500, it ditched the ignition map selector button, slightly reducing complexity of the controls available.

A Baja Designs Squadron LED light assembly sits inside the stock headlight shell for safety during daylight hours. Morgan also prefers that small bit of weight up front, insisting it helps stabilize the bike.

Honda CRF450X custom bolt-on mount fabricated by 74 Welding .
When running the bigger Baja Designs Squadron XL lights, this custom bolt-on mount fabricated by 74 Welding holds things in place as there are two lugs on the steering head from the factory that are easily drilled and tapped. For the 1000 with its longer night run, however, the crew might just weld it for added security.Mark Kariya

When the sun’s not shining, that gets replaced quickly with a Baja Designs Squadron XL light setup attached to a special bolt-on mount on the steering head that 74 Welding fabricated; 74 also tabbed the mount for the Stella tracker SCORE mandates. Baja Designs rewinds the stator to run the big lights, though the standard ignition suffices for the small Squadron. Unlike the previous-generation ’X, the rectifier in the new model is large and so far has been robust enough to not fail.

Maxima lubricants meet the requirements for all necessary applications on the SLR machine, which San Diego Powerhouse preps for race day. “[Bobby Youngs there] does all the little things like the brake snake, all the little tiny things that add up and make a difference is done by him,” Morgan reveals. One of those little things is shaving the casting marks off the lower triple clamp, resulting in a smooth and almost lustrous piece pleasing to the eye as well as the touch.

Aesthetics aside, the SLR Honda CRF450X has responded well to its accelerated development and moves the model a step above the previous generation. Who knows where it’ll stop?

As Samuels predicts, “Each race, we’ve gotten a lot better and a lot better [getting the new bike dialed in], and I think we learned a lot this race on making a few more changes, too, to make it even better for the 1000.”

Considering they beat the second bike by just over an hour at the 500, their competitors have their work cut out.