2009 Rocket Exhaust Honda CRF250R

Since its inception, the Honda CRF250R motocross motorcycle has garnered top honors in our annual 250F Motocross comparison four out of the last five years. Thus, it’s pretty difficult to argue against just how good of a motorcycle the CRF is in stock form. Yet we’ve always been curious how much more performance could be unlocked through careful preparation and some key aftermarket performance goodies.

So we turned our 2009 Honda CRF250R over to the folks over at Rocket Exhaust for a full performance makeover. The Lake Elsinore, California-based company went to town, outfitting our motocrosser with the latest go-fast parts from companies that know a thing or two about getting around the racetrack.

It’s a Rocket

Rocket began by modifying the heart of the motorcycle, the engine. Inside, all of the actual hard parts remain stock in order to ensure reliability. What is changed however is the shape of the cylinder head, including the intake and exhaust ports, as well as the valve seating area, which magically unlocks hidden power by allowing the engine to flow fuel and spent exhaust gases more efficiently.

“One method tuners use to extract more power out of an engine is to put in a more aggressive camshaft or big-bore piston,” says Don Leib, owner of Rocket Exhaust. “And while that method works great, by retaining all the stock components and modifying just the cylinder head you get the performance you need without sacrificing reliability.”

In stock form, most CRF250R riders will tell you it’s tough to achieve perfect carburetor jetting. At some point that dreaded engine hesitation or bog happens, usually at the worst possible time. And no matter what jetting tricks we’ve tried, we’ve never been able to totally eliminate the problem. Until now, that is. An R&D Power Bowl replaces the stock carburetor float bowl and is designed to more efficiently atomize intake fuel mixture.

“The stock CRF250 is tough to jet properly. It’s the only 250 with a 40mm carb,” says Leib. “That’s a problem. With a 4-Stroke engine you need to have the accelerator pump circuit functioning at its best. And the R&D bowl bleeds air in the accelerator pump circuit better by creating another path for the fuel to get back to the float bowl.”

Another benefit is that the R&D bowl allows the tuner to adjust the accelerator pump leak jet without having to loosen or remove the carburetor from the motorcycle. Also installed was R&D’s Flex Jet, which allows the tuner to make a fuel screw adjustment right at one's finger tip.

On the exhaust side of things, Rocket fitted its proprietary full-race exhaust system with optional shorty-style muffler. It’s designed for an amateur racer or enthusiast that doesn’t want to sacrifice outright performance for reduced noise (standard muffler brings noise decibel to 96). As opposed to a stock twin pipe system, the Rocket setup utilizes just one muffler on the right-hand side which further reduces weight without sacrificing performance. The header pipe is constructed out of stainless-steel while the muffler is made from billet aluminum. Overall fit and finish is superb, especially when you consider its reasonable $524 price tag. Another plus is that Rocket has the ability to build you a custom pipe based on your specific requirements, if so desired.

The final elements in the engine performance department include R-Tech Pro V.1 Race Fuel and a Vortex Ignition. The ignition system allowed Rocket to maximize all of the individual performance enhancements by building a custom ignition map for our motorcycle. Additionally, the Vortex module allows the tuner to store up to 10 different ignition maps which can then be selected via a dial on the top of the box. Thus, you can tune your motorcycle for any type of conditions (hard terrain, soft terrain) you might encounter. A Hinson clutch basket, inner hub and pressure plate also sits between the engine cases and offers added feel and durability especially during hard rides.

Getting Connected

Arguably one of the biggest limiting factors in terms of how fast you can ride is your bike’s suspension.
But with so many suspension tuners to choose from, finding the right one can be overwhelming. That’s why when it comes time to select a tuner the single most important aspect to consider is their experience. That’s why Rocket enlisted some help from the boys over at Factory Connection.

With locations on both coasts as well as its factory-supported Supercross and Motocross teams, no one does more suspension testing. Factory Connection disassembled our Honda’s fork and rear shock and installed properly-rated springs and valving based on our weight, skill level, type of riding we do, as well as any specific preferences we had. Another plus is that if you ever need your valving modified, say for a specific type of ride you have planned or if you get faster or your needs change, they provide updates free of charge.

“The CRF’s stock components are really good,” said Factory Connections Mike Rodgers. “But what most riders don’t realize is that inside you have a tremendous amount of tunability. And that’s what we do at Factory Connection. We get your bike's suspension dialed so it’s best for you.”

To fully maximize suspension performance on the track we also opted for their bolt-on shock linkage. The rate at which the shock travels through its stroke is said to provide more compliance when encountering braking and acceleration bumps.

Eye Candy, Please

Visually, Rocket liberally adorned our bike with eye candy that not only looks cool but functions as well. Jet black Excel wheels laced with tough Bulldog spokes and beautiful anodized Talon billet aluminum hubs were fitted. The front hoop size remains the same as stock but the rear wheel is 0.2-inches wider (1.95-inch is stock) which allows us to utilize a larger 110/80 rear tire. The wheels are shod with Dunlop’s new generation Geomax MX51 off-road tire.

Final drive gearing was also lowered to allow the rider to get to be able to reach the CRF’s stout top-end power more quickly. Specifically a Tag Metals 13-tooth front sprocket and a 52-tooth rear sprocket are used and driven by a gold RK chain. A larger diameter 270mm Brembo front brake rotor helps keep speed in check.

More aggressive looking Cycra Powerflow bodywork replaced the stock pieces and is covered with Rocket’s own One Eighty graphic kit, while Dirt Digits stepped in with its durable and easy-to-install preprinted number backgrounds. LightSpeed finished it off with a trick carbon fiber skid plate, engine guard and chain guide.

Helping to make the rider more comfortable are Tag handlebar, bar clamps and grips, while a set of ultra-wide IMS footpegs and Sunline shift lever and hand controls give the bike that factory-racer look while making for a more usable rider interface.

How does it Ride?

To find out how the Rocket CRF250R performed we headed to Zaca Station in Santa Barbara County, California. Nestled in a lush green valley, Zaca is the definition of real outdoor motocross. Huge jumps, fast sweeping turns, technical uphill and downhill sections, not to mention some cool rhythm sections; this track has it all and is definitely worth the drive.

Out at the motocross track the difference from stock was night and day. From the moment you fire the engine up you can literally hear how much snappier the Rocket CRF is. Twist the throttle and feed out the clutch and you’ll notice the improved feel from the clutch internals right away as well, which makes rocketing off from a dead stop easy and precise.

Any time the throttle is opened the bike responds immediately, almost like it was fuel-injected. Engine hesitation is a thing of the past and the bike always carburetrates cleanly. The Rocket CR builds rpm more voraciously than stock, yet power remains smooth. Throughout the rev range power feels stronger but still isn’t enough to intimidate even a novice rider. Keep the throttle pinned for a few seconds and you’ll be rewarded with an earlier mid-range punch which rapidly morphs into a top-end power rush that never seems to end. CRF250Rs have always been rev happy and the Rocket machine continues to trend.

“The difference over stock is unbelievable,” said pro-level MotoUSA test rider Matt Armstrong. “From the second you get on the gas the bike just takes off. It’s way more responsive and pulls much harder everywhere. I also can shift earlier just because the motor’s got so much more pull.”

We were equally impressed by just how well the modified suspension components function. When compared directly to the stock set-up, the Factory Connection suspension gave the rider much more feedback to what’s happening at the business end of the Dunlop tires. This allows you to more accurately place the motorcycle where you want it to go.

“What I really like about the suspension is that you always know where you’re at on the bike,” said Armstrong. “It makes it easier to get into and out of a rough or bumpy corner.”

We were also pleased with the improved suspension action. Overall, it felt much smoother throughout suspension stroke. We also really like just how much more composed the motorcycle was especially when tackling braking or acceleration bumps. Where the stock bike’s rear end had a tendency to quickly come around, the Rocket CRF would stay inline.

The upgraded front brake also allowed the rider to use slightly reduced pressure on the front brake lever to get the bike slowed. While the difference over stock wasn’t huge, over the course of an afternoon it will contribute to less rider fatigue and more control.

Outright grip from Dunlop’s new Geomax tires continued to impress us and even with the added engine power the rear knobby claws the ground with an obscene about of traction. Armstrong was also fond of the added creature comforts like the wider footpegs and thicker handlebars which provided a more secure work area for the rider to ply their trade.

“Overall this thing is way sharper than the stock bike and it just makes it more fun to ride,” commented Armstrong. “Not only that, but it’s easier to ride fast. On the stock CRF you’ve got to push much harder to get the same result and it just wears you out faster.”

Final Thoughts

At the end of the day we were extremely pleased with our Rocket-modified CRF250R. It is a much sharper motorcycle all the way around. The engine is way faster yet it’s smooth and easy to use, plus the engine modifications don’t sacrifice that trademark Honda reliability, which is why we opted for a CRF250R in the first place. As for the suspension, it left us with an elevated level of control that made riding the motorcycle faster much easier. And, in reality, that’s what it’s all about: going as fast as possible with the least amount of effort. It’s what the factory teams spend umpteen thousands of dollars on and it’s exactly what Rocket has done with our Honda CRF250R.

Perhaps Armstrong summed it up best: “Honestly, there isn’t a part on this bike that I wouldn’t purchase for my own bike.”