2019 Off-Road Factory Racebikes—Zach Bell’s Kawasaki KX450

Motocross racer turned GP winner discusses his bike setup

Kawasaki KX450 left profile.
Zach Bell likes to keep his Chaparral Motorsport/Precision Concepts Kawasaki KX450 remarkably stock, mostly in deference to his smaller stature. Coming from a pure motocross background, he's had to relearn some things like setting suspension for races that are several hours long.Mark Kariya

Zach Bell had a pretty good career going in professional motocross. Coming up through the amateur ranks, he won several championships at Loretta Lynn's plus the 2012 AMA Nicky Hayden Horizon Award/Motocross before landing a spot on the Geico Honda team. A number of serious injuries interrupted his progress on the pro circuit and kept him from doing any racing for a full year and—as is unfortunately common in all sports—his name faded from the limelight. After recovering, Bell decided to do some off-road racing in hopes of rebuilding his fitness and maybe getting back into motocross.

However, he found his speed translated well into this new world and quickly established himself as a front-runner in both WORCS and AMA District 37 Big 6 Grand Prix (which would become the FMF AMA National Grand Prix Championship Series in 2019).

Bell won the GP championship in 2017 aboard an Ox Motorsports Honda, then finished a close second last year on a 3 Bros./STI Husqvarna. For 2019, he signed with the Chaparral Motorsports/Precision Concepts Kawasaki team, which is somewhat of a full-circle thing as he'd been a Kawasaki Team Green rider in his early days as an amateur motocrosser. This year Bell is focused on WORCS where he's fifth after five rounds, he's claimed three victories in the first five rounds of the NGPCs, unofficially putting him third in points despite missing two rounds due to scheduling conflicts.

Precision Concepts suspension setup.
Bell had to go to a softer feel for his Precision Concepts suspension setup via a combination of stiffer springs and softer valving than he would’ve used in his MX days.Mark Kariya

We caught up with the popular crossover rider in Primm, Nevada, before he won the latest round of NGPC that afternoon over Purvines Racing Yamaha’s Justin Seeds and Johnny Campbell Racing (JCR) Honda’s Trevor Stewart, the reigning series champion. There, he explained how he’s modified his KX450 and how different it is from how he’s set up motocross bikes in the past for someone his speed and size, which is 5-foot-4, 138 pounds.

“My bike’s kind of small to begin with,” Bell begins. “I hopped on [teammate] Blayne [Thompson’s] bike and his was a lot bigger.

“Mainly when I was racing Supercross and motocross, I always had a stiff [suspension] setting just because we were plowing through stuff,” he notes. “That’s kind of what we do [in off-road as well], but we go two hours and our bodies need to be able to take that for the two hours, so going [to comparatively] soft [suspension] was tough for me because we hit stuff so fast and when the bike doesn’t absorb it a lot, our bodies start to take it. That’s when we start to find better lines.”

Rekluse automatic clutch behind clutch cover.
Behind that clutch cover is a Rekluse automatic clutch, making Bell one of the few Pros to use one. He sees only advantages to it, both in off-road and MX/SX applications.Mark Kariya

Despite his size, his speed dictates using stiffer springs though Bob Bell (no relation) of Precision Concepts compensates a bit with milder valving. Zach prefers to set sag at 106mm. Xtrig triple clamps hold the fork legs while Ride Engineering provides its pullrods as well as various plugs and caps. “We’ve done one day of testing this year and that’s basically what I’ve stuck to. We made a few minor adjustments [at the Sprint Hero race in] Peoria, [Arizona], just because of the rocks and stuff, but other than that, no [big suspension changes]. We bleed the forks after each ride. Other than that, I don’t touch the clickers; I feel pretty confident with what we have.”

He admits, “Adjusting to the suspension changes and the steering stabilizer [was major]. I don’t like my handlebars feeling like they’re stuck; I like to be able to move them around like it’s free.

“Then this year, I switched to a Rekluse and started running the automatic clutch. It takes a lot off your hands. I had trouble with calluses and through the [technical] rocks, it makes it a lot easier on me—I can focus on getting through them instead of trying to keep the bike [running].

“So yeah, there’s just been a few things [I’ve changed from a motocross-oriented setup] but not a whole lot—just suspension changing and clutch. I wish I would’ve done that a long time ago; even in Supercross and motocross it’s something good to have when you’re tired out there.”

CryoHeat’s unique head porting and engine assembly with an Acerbis polymer skid plate.
CryoHeat’s unique head porting and engine assembly after cold treatment assure smooth power as well as reduced friction. An Acerbis polymer skid plate helps protect the cases from off-road abuse.Mark Kariya

In some areas, Bell isn’t particular while he has distinct preferences in others. The Mika Metals handlebar, for instance, is an off-the-shelf model, though he says, “I’m kind of [partial to a] low bend. We actually cut the bars down a half inch on each side just to get my arms more neutral and not so hanging out.” Bell uses half-waffle A’ME grips, his teammate Thompson depending of full-waffle versions.

“I run Maxxis tires—I believe it’s the [Maxxcross] SI, Maxxis’ [intermediate] compound.

“Everything’s pretty much basic on the bike. I’m not too picky on things. I like to run everything pretty much stock; I like the feel of stock stuff, more production stuff. That’s even when I was back with Geico [Honda] or [Rockstar Energy] Husqvarna [Factory Racing]—I always went to production just because it was more plush for me. With the A-kit stuff I couldn’t ride it; it was just way too stiff for me.

“The stuff we have on the bike is pretty basic; anyone can buy it at the stores—nothing too trick besides the clutch, which is mainly the big [change] on [my] bike.”

In other words, Bell generally finds something he likes and sticks with it. The MotoSeat, for example, “is kind of what I’ve been running all [through my new] off-road [career]. I never put a bump in it my entire life. I put the [five-rib model] on just because we’re out there for so long, we need to have that traction with our butt.”

A full Pro Circuit exhaust and a standard MotoSeat with five gripper ribs.
A full Pro Circuit exhaust improves delivery without making it too abrupt. Bell uses a standard MotoSeat with five gripper ribs though he eschews a speed bump.Mark Kariya

IMS provides both the 2.5-gallon fuel tank with quick-fill receiver and the standard height, sharp-tooth Core footpegs. Despite coming from his MX background, the larger fuel cell doesn’t seem to bother him and he points out, “We raced with the big tank [at a few outdoor motocross Nationals] a few years ago [on Hondas] just to have fun out there.”

An RK O-ring chain spins the Mika Hybrid rear sprocket, with Zip-Ty Racing axle block/chain adjusters keeping things lined up and TM Designworks providing the chain guide. “At [the fast NGPC round in] Twentynine Palms, [California,] I think we went to 14/49 or something. I’m normally [running] 14/50; we kind of stay around that range, just because with a Rekluse I have everything I need in that and with the gearing, I’m so light I don’t need much more power anyways.”

Kawasaki KX450 right profile.
An overall look reveals more like the IMS tank with quick-fill receiver and Maxxis Maxxcross SI tires, though you can’t see the NitroMousse foam inserts inside those tires.Mark Kariya

Externally, the Pro Circuit exhaust stands out, but to smooth and enhance power delivery, Bell confides, “CryoHeat does all the [head] port and polishing, does all that just to get the bike running smoother. I even told [team manager] Robby [Bell (again, no relation though he’s Bob Bell’s son)], ‘I don’t want anything faster than this just because I’m so little. Let’s keep everything minimal; do what you guys want to do to the bike, but let’s just keep it pretty [mellow] for me.”

Mellow or not, the combination of Bell and his KX450 is a proven winner and a make a formidable pair.