TICK-TOCK: STAPO’S COUNTDOWN TO A RACE-READY 2025 HONDA CRF450

The grey Acerbis plastic and grey Guts seat cover made the CRF450 an eye-catcher in the pits.

BY DENNIS STAPLETON

The World Vet Championship might return to the same venue every year, but it’s never the same race. Glen Helen is always transformed into a brutal proving ground, and everyone seems to have a story. From frantic last-minute prep on bikes with wheels stripped for anodizing to hopes of dropping down a class, it’s chaos until the gate drops—and then, it’s as if the riders are on testosterone shots, swerving like teens at a roller rink.

Some years, I race. Other years, I focus on running my rental bike business and building MXA project bikes for the event. This year, skipping the Mammoth Mountain Motocross and bowing out of the annual trip to Loretta Lynn’s Ranch had left me with a stark realization: I couldn’t afford to sit out the 40th Annual World Vet Championship. At my age, letting speed fade is not an option unless I want to take out a bank loan from JP Morgan to ride nonstop next season just to catch up.

Dennis (184) raced in both the Over-30 and Over-40 Pro classes at the 40th Annual Dubya World Vet Championship. He was ninth in the 30s and fourth in the 40s.

After the “2025 MXA 450 Shootout,” I quickly loaded up the 2025 Honda CRF450 and drove home with a plan to build a top-tier race bike in just four weeks. This wasn’t going to be easy; I needed to practice during that same window, and this was my only race bike.

AFTER THE “2025 MXA 450 SHOOTOUT,” I QUICKLY LOADED UP THE 2025 HONDA CRF450 AND DROVE HOME WITH A PLAN TO BUILD A TOP-TIER RACE BIKE IN JUST FOUR WEEKS.

First, I reached out to Chad Braun at XPR to create an engine that could handle Glen Helen’s infamous long start straight. The stock 2025 Honda CRF450 engine is rider-friendly and responsive, but 55 horsepower was not gonna cut it on a 70-mph sprint to the first turn—no matter how steeply banked it is. I needed AMA 450 National power, something closer to 63 horses. Luckily, a friend with a spare engine loaned it to me so I could keep riding while waiting for Chad and the XPR team to work their magic.

XPR’s Chad Braun took the stock 55-horse CRF450 engine and turned it into a 63-horse powerhouse.

Given that the HRC Honda team runs a Yoshimure RS-12 exhaust system, so did Dennis.

Next, it was on to the suspension. I had worked with Brandon Peterson at AHM before, so I contacted him about dialing in my suspension to match the updated 2025 Honda linkage and frame. The stock setup wasn’t going to cut it, and quality test days during the time I had were hard to come by. Brandon, who had already put time into the 2025 Honda, understood what I needed: more fork hold-up for Glen Helen’s steep downhills and matching stiffness in the shock for balance. The AHM team turned it around fast, giving me time to spin laps and get comfortable.

Glen Helen’s high speeds, big hills and endless bumps require stiffer-than-stock suspension. Dennis relied on AHM for his setup.

Works Connection’s rear-brake master cylinder guard.

The Yoshimura header has an extra layer to protect against roost.

With the core pieces handled by outside pros, I had to tackle the rest of the bike by myself. This sounds straightforward, but I also had to prep five World Vet rental bikes for three Japanese and two Argentinian riders, plus MXA assigned me three Boyesen project bikes for the race. It made for lots of long days. Add to the mix that I have to manage my dad’s Cobra business and fulfill my testing contracts, I felt like a dog chasing its tail. Thankfully, MXA’s Brian Medeiros, Justin Muscutt, Josh Mosiman and my industry friend Hudson jumped in to help, making the final week manageable.

THANKFULLY, MXA’S BRIAN MEDEIROS, JUSTIN MUSCUTT, JOSH MOSIMAN AND MY INDUSTRY FRIEND HUDSON JUMPED IN TO HELP, MAKING THE FINAL WEEK MANAGEABLE.

By the time Chad Braun had finished the engine, it was a rocket ship. I had time for one warm-up race at Glen Helen, where I discovered that the power was undeniable, but the shock struggled with the added horsepower. My buddy Casey Casper helped me make adjustments throughout the day, balancing the suspension to match the newfound engine performance. The results weren’t stellar, but the setup was ready for the 2024 World Vet Championship.

THE BIG WEEKEND

Saturday at the World Vet is when they hold the Over-40 and Over-50 Pros races. My focus was the Over-40 Pro class. If you’ve never been to the World Vet, I can’t really explain what the World Vet starting line looks like—it feels like the 91 Freeway at rush hour. It is overwhelming, especially for first-timers or international riders. The vibe is so intense that just waiting for the board to turn sideways has my heart hitting its rev limiter, and when a well-meaning friend gives me a friendly pat on the back before the gate drops, it almost makes me jump out of my skin.

There are always battles within battles. In the Over-40 Pro class, MXA’s Dennis Stapleton (184) and Dirt Bike’s Mark Tilley (95) fought for Hi-Torque honor. Dennis’ 5-4 edged out Mark’s 4-5 for fourth overall.

It takes a lot of work to get to the starting line — body, soul and bike have to be in harmony! Even I underestimated how much time and effort it takes to prepare for the one “big race” of my year. Most motocross racers can relate; we don’t always have the best memories. We forget that a year ago we said, “I’ll never go through this again.”

My job and life revolve around dirt bikes, but at my age, I’m extra picky about my bike setup, and I don’t feel comfortable pushing my limits on a bike I don’t trust. Thus, it takes me extra time to test and put together my race program for big races like the World Vet.

Once the gate finally drops, I don’t remember all the late nights listening for the FedEx truck delivering that long-lost part or wondering if I torqued the swingarm pivot bolt. It’s all or nothing on the charge to the first turn. I launched out with the front pack, holding my own for the first laps before settling into a battle with Mark Tilley from Dirt Bike Magazine. We swapped positions multiple times before he edged me out for fourth, leaving me in fifth. I love Mark, but just like any factory rider who wants to beat his teammate and be the top dog on the team, I always want to beat my friend Mark and be the top Vet rider under the Hi-Torque Publications umbrella (Dirt Bike is the sister publication to MXA).

Dennis prefers the old-school MX3S front tire combined with an MX33 rear tire.

The ProX gold chain runs on a TM Designworks Slide-N-Guide chain guide system.

For the long, rough and rugged Glen Helen circuit, Dennis protected his radiators with Twin Air radiator sleeves.

In moto two, I pushed hard to stay with the leaders, but got overeager in turn two, falling back to around 10th. Determined to recover, I charged down the big hill with too much speed, nearly flying past Tilley in what probably looked like a take-out attempt. Wrestling the CRF450 back under control, I fought through the choppy track, chewed up by 1200 riders, to finish fourth in the moto and fourth overall. I had hoped to do better, but at least I beat my buddy Mark!

WRESTLING THE CRF450 BACK UNDER CONTROL, I FOUGHT THROUGH THE CHOPPY TRACK, CHEWED UP BY 1200 RIDERS, TO FINISH FOURTH IN THE MOTO AND FOURTH OVERALL.

Sunday brought the Over-30 Pro class. Despite waking up sore, I felt motivated. In the first moto, I started strong, keeping pace with the lead pack for three laps before finishing seventh. Those opening laps felt like a bigger victory than Saturday’s results. The second moto, however, was really rough. A collision with a water barrier in turn three sent me to the ground. The track resembled a battlefield after a week of relentless use. I clawed my way back to 11th, securing ninth overall. When the World Vet weekend was over and I was driving out of Glen Helen’s front gate in one piece, I felt like the real winner.

THE LOWDOWN ON MY CRF450 BUILD

Here’s the rundown of my 2025 Honda CRF450 setup:

Engine. XPR complete build with Vortex ignition.

Fuel VP Pro6. XPR made all the decisions about the engine, thus the fuel was their choice, too. The XPR engine enhanced the already rider-friendly 2025 Honda CRF450 powerband. Known for its fun torque at low rpm, the XPR engine with VP Pro6 fuel adds smoother and broader mid-to-top power, improving third-gear rideability.

Suspension. I chose to have Brandon and his crew at AHM do my fork and shock re-valve. While Honda’s stock CRF450 suspension is almost perfect for the average Vet racer, this wasn’t the average Vet race. I needed firmer settings to handle the demands of a big event like this.

Exhaust. Yoshimura RS12 is a trusted name for Honda CRF450s. Yosh supplies pipes for the Works Editions and the Honda factory riders. The RS12 delivers durability, performance and a quieter muffler—an added bonus for this build.

Tires. I run Dunlop tires, but probably not the models that most people choose. I run an MX3S front and a 120/90-19 MX33 rear. I still favor the previous MX3S front tire for its unmatched feel. The MX33 rear performs well on the track, but concedes some traction on starts, especially at a big race where lots of riders are willing to gamble on the scoop tire working on the start—even if the scoop tire might struggle in the harder portion of the track, especially late in the moto.

Footpegs. I run Raptor titanium footpegs because they can be set 5mm back, which matches my riding style. I tend to ride towards the rear of the bike, loading the shock. This setup also opens up the shifter and brake pedal, addressing the notoriously short Honda shift lever.

Plastics. Acerbis was a great choice because they offer red and gray 2025 Honda plastic, which made my race bike stand out. Their unmatched fit, finish and color options make Acerbis my go-to source.

Graphics. DeCal Works supplied a custom graphics kit tailored to our project bike’s red/gray plastic. Their unique design added the finishing touch.

Seat. Honda’s stock seat foam tends to get soft quickly, but Guts Racing offers a complete bolt-on solution. Their seat maintains comfort and durability for all race conditions.

Air filter. Twin Air’s pre-oiled air filters are essential for any race machine. Twin Air’s 1.8 radiator cap is perfect for Honda, because the stock 1.1 cap tends to be pushed to the limit on a high-temp racing engine. Twin Air’s radiator sleeves protect fins and prevent mud buildup, extending the life of the radiators.

Works Connection. Works Connection’s Pro Launch start device is a racing essential. Their axle blocks include precise adjustment lines for easy chain alignment, while the reservoir brake cover ensures a smooth transition for my boots.

TM Designworks chain guide. TM Designworks chain guides are durable and reliable, perfect for Glen Helen’s tough conditions. The ProX chain, made in Japan, guarantees no DNFs over the weekend.