2005 Honda CRF450R And Suzuki RM-Z450 Exhaust Test - Dirt Rider Magazine

One of the first things a rider does to his or her new scoot is bolt on a new exhaust system. The stock exhaust systems on most of the new four-strokes are quite good since the manufacturers try endless variations before releasing a bike to the public. For aftermarket companies, it's simple to raise the bar as far as quality and weight go with trick materials and painstaking craftsmanship. But to completely blow away the stock system's performance and make the aftermarket model worth its princely price tag, they had better do their homework.We opted to test two bikes: the most-popular motocross bike ever, the Honda CRF450R, and its new challenger, the long-awaited Suzuki RM-Z450. Both are incredible in stock trim, but we wanted to see how much we could improve the bikes. It mostly comes down to personal preference. In some cases, an aftermarket exhaust system may not generate much more sheer horsepower and torque but will boost it on different points of the power curve. Some exhausts offer more bottom and mid, while others more mid to top-end. Whatever power characteristics you are looking for in an engine, the exhaust system is a great way to coax out a curve to suit your riding style.All the systems in this test worked surprisingly well, and the craftsmanship on all was incredible. We covered all bases by testing at three different tracks, making dyno runs, weighing the pipes and, more important, sound testing the exhausts. This last test scared away a few manufacturers, but sound requirements are very important and something Dirt Rider takes seriously. A few companies are missing from this comparison because either they didn't want to meet the AMA Pro Racing's 102-decibel limit we specified or they didn't have a product available at the time of testing. After weeks of punishing the parts, we compiled our results and were amazed with how close some of the systems are to each other. So read up and see which one is-or isn't-for you.Test Notes
This test comprised high-end exhaust systems; chances are a given manufacturer makes a less-expensive version.The sound test procedure was performed by Chemhelp's professionals (www.chemhelp.com) under controlled conditions. Chemhelp uses the same meters employed by the Forest Service, BLM and California State Park rangers, but these sound readings may vary in the field. We opted to go with AMA Pro Racing's 102-decibel standard.Sound fact: Decibels are logarithmic and do not add directly; that is, two 80-decibel bikes do not produce 160 decibels but rather 83. Thus, as a very rough rule of thumb, reducing the sound of a bike by 3 decibels has about the same effect on the "acoustic environment" as cutting the number of off-road motorcycles present by half.Testing Conditions
Where: Piru Motocross Park, I-5MX and Staben Ranch
Elevation: 500-3000 feet
Temperature: 68-75 degrees
Fuel: Pump
Jetting: Stock for both bikesOverall score: Each rider rated each exhaust system on a scale of 1 to 100, then we combined all scores to reach an average. The stock system was used as our baseline to which every system was compared. Ratings were decided by track performance only.Our Final Word
As you can see by our test results, all the exhaust systems have strong points, and surprisingly, none of them had any true weak spots when it came to performance. Although we went with AMA Pro Racing's 102-decibel standard for this test, we feel strongly that the noise level still needs to be reduced significantly. Perhaps in our next exhaust test we'll use a limit of 98 decibels. If we want to keep our tracks open, sound testing must be taken seriously. In this case, all but the Akrapovic are close to 3 decibels louder than stock, which means twice as loud or more. After mounting up all of the exhaust systems a total of five times, we became really familiar with the craftsmanship of each system. All the manufacturers have stepped up their quality control and are constructing with high-grade materials. We did, however, run into a few problems with the spring-mounted pipes as they simply required more time to mount than the ones that don't employ springs. But incorporating spring mounting means a longer life for these thin and exotic materials. Overall, all the pipes in this test are worth the money, and again, we were amazed with how close they all are to each other.Price: $794.85 Contact: Your Local Honda DealerMaterial: Titanium header with an aluminum canisterStyle: Full two-piece systemFit: Fits perfectly and mounts up in just a few minutesWeight: 6.99 lbSound: 98.0 dBOn the track: The stock exhaust system works really well off the bottom with a surge of power in the midrange. Top-end power pulls long and hard before hitting the rev-limiter but could use a bit more overrev. The stock system works well at all types of tracks.Overall score: 9O.OStock PipeS
Suzuki rm-z 450
Price: $719 contact: your local suzuki dealer
Material: Titanium header with an aluminum canister
Style: Full two-piece system
Fit: Perfect, installs in minutes.
Weight: 7.06 lb
Sound: 95.9 dB
On the track: The stock exhaust offers great off-idle power and good bottom-end and top-end. The middle rpm range just feels flat and unresponsive, especially when compared with the Honda, which is strong in the midrange. The power curve provides smooth, controllable power, making the bike rider-friendly for all skill levels.
Overall score: 8O.OHonda CRF45OR
Price: $705.00
Contact: See your local dealer;
www.akrapovic-exhaust.com
Material: Full titanium
Style: Full two-piece system
Fit: Fits perfectly using two springs to hold the header pipe in place. Mounts up in just minutes
Weight: 4.85 lb
Sound: 98.7 dB
On the track: Has a very smooth, slow-revving bottom-end. It has good roll-on power but is not snappy. Worked best in dry blue-groove conditions. Midrange power feels broader as it pulls longer than the stock system. Top-end power is very smooth and pulls longer, requiring less shifting. It was easier to ride in third and fourth gear with more roll-on power.
Overall score: 94.OAkrapovic evolution
Suzuki RM-Z450
Price: $705.00
Contact: See your local dealer;
www.akrapovic-exhaust.com
Material: Titanium
Style: Full two-piece system
Fit: Fits perfectly using two springs to keep the headpipe in place; mounts in minutes.
Weight: 4.98 lb
Sound: 96.8 dB
On the track: Off the bottom, this system feels as good as the stock components, but it comes alive in the midrange. There, the power pulls strongly-much harder than the stock system. Top-end power is also very strong and pulls longer compared with stock.
Overall score: 96.OHonda CRF45OR
Price: $515.95
Contact: 951/808-1114; www.dubachracing.com
Material: Stainless steel header with aluminum canister and end-cap
Style: Full two-piece system
Fit: Fits perfectly using all the stock hardware; mounts up in just minutes without springs.
Weight: 6.24 lb
Sound: 101.4 dB
On the track: Bottom-end power pulls super strong and carries over to a very meaty midrange. You can really feel a big difference in third and fourth gear as you can carry both gears longer with less clutch. The power curve allows you to use the torque; you can lug the bike much longer. Top-end power is solid, but the most-noticeable change is in the bottom and middle rpm ranges. This exhaust was one of the favorites in rough conditions.
Overall score: 98.ODr. D
S.s.
Suzuki RM-Z450
Price: $515.95
Contact: 951/808-1114; www.dubachracing.com
Material: Stainless steel headpipe with an aluminum canister and end-cap
Style:Full two-piece system
Fit: Fits perfectly using all the stock hardware; mounts up in just minutes with no springs.
Weight: 6.10 lb
Sound: 101.1 dB
On the track: The bottom-end pulls a tad better than the stock system did, but the DR. D exhaust really comes to life in the midrange; the power is much more usable there. It pulls longer, requiring less shifting. Top-end power also pulls longer before bumping the rev-limiter.
Overall score: 97.OHonda CRF45OR
Price: $899.95
Contact: 310/631-4363; www.fmfracing.com
Material: Titanium header and midpipe with a carbon-fiber canister
Style: Full three-piece system
Fit: The system takes a bit of time and patience to mount; the multiple springs are a bit annoying, requiring FMF hardware that comes with the system.
Weight: 4.58 lb
Sound: 100.1 dB
On the track: Bottom-end power is very smooth and similar to stock. The midrange is where the meat of the power is with the FMF system; the midrange power is strong and has more torque. The usable power curve allows second and third gear to be ridden longer. Top-end power has a bit more pull compared with the stock system.
Overall score: 97.OFmf Powerbomb Factory 4.1 Carbon
Suzuki RM-Z450
Price: $899.95
Contact: 310/631-4363; www.fmfracing.com
Material: Titanium header and midpipe with a carbon-fiber canister
Style: Full three-piece system
Fit: This exhaust demands a bit of time and patience to mount; the multitude of springs is a bit annoying, requiring FMF hardware, which is included.
Weight: 4.22 lb
Sound: 98.8 dB
On the track: The FMF system has a bit more usable power off the bottom than the stock arrangement. Midrange power is much more usable and is really where the meat of the muscle is with this system. The FMF exhaust likes to be short-shifted; it worked best in dry, slippery conditions. Top-end power was decent, but it revs out fairly fast before knocking on the rev-limiter.
Overall score: 94.OHonda CRF45OR
Price: $864.99
Contact: 888/610-4242
Material: Titanium
Style: Full three-piece system
Fit: The system requires Leo Vince hardware (included) and uses multiple springs and a carbon-fiber canister hanger. It takes some time to install, but reading the directions will save you lots of time. This springs are annoying, but it comes with a trick spring puller and high-quality hardware.Weight: 6.18 lb
Sound: 101.5 dB
On the track: A strong power surge at the bottom allows the bike to be ridden with a lot less clutch out of tight corners, the midrange is very usable and spread out much further than stock and the top-end pulls longer. The power characteristics with this system were really noticeable in second to third gears, which we could use much longer.
Overall score: 95.5Leo vince x3
Suzuki RM-Z450
Price: $864.99
Contact: 888/610-4242
Material: Titanium
Style: Full three-piece system
Fit: This system requires some time to install, as well as the included Leo Vince hardware and a carbon-fiber canister hanger. The X3 uses a ton of springs but comes with a trick spring puller and high-quality hardware. If you read the directions, that will save a bit of time. Weight: 6.15 lb
Sound: 100.8 dB
On the track: Bottom-end power has more snap that pulls much harder compared with the stock system. Midrange power also has more snap and feels as if it offers more torque. The top-end pulls longer before hitting the rev-limiter. All of our test riders were able to use second and third gear much longer with a lot less shifting.
Overall score: 97.oHonda CRF45OR
Price: $799.95
Contact: 951/738-8050; www.procircuit.com
Material: Titanium
Style: Full three-piece system
Fit: The PC system uses springs to attach the midpipe to the canister and mounts easily in just minutes with the stock hardware.
Weight: 5.72 lb
Sound: 99.2 dB
On the track: Very smooth off the bottom, similar to the stock system. The midrange comes on strong, pulling hard into a very solid shot of top-end power. The top-end feels as if it pulls longer before hitting the rev-limiter, and the power doesn't fall on its face when the limiter kicks in as the PC system serves up a nice shot of usable overrev.
Overall score: 97.oPro circuit
Ti-4 gp
Suzuki RM-Z450
Price: $799.95
Contact: 951/738-8050; www.procircuit.com
Material: Titanium
Style: Full three-piece system
Fit: The PC system mounts up easily in minutes and uses springs to attach the midpipe to the canister.
Weight: 5.42 lb
Sound: 99.9 dB
On the track: Bottom-end power is strong and pulls hard into the midrange. Top-end power is much more usable than the stock pipe, as the PC revs out further with a lot of overrev. The PC system has usable power everywhere and can be lugged or revved to the moon. The delivery is also very smooth across the power curve.
Overall score: 98.oHonda CRF45OR
Price: $699.98
Contact: 800/211-2767; www.twobros.com
Material: Polished titanium with a billet-aluminum end-cap
Style: Full three-piece system
Fit: We had no problems mounting this system; installation took only a few minutes. It features a very trick mounting system-the midpipe and the canister bolt together. The hardware is included and even comes with an Allen wrench.
Weight: 5.01 lb
Sound: 100.8 dB
On the track: The M7 has a strong, snappy bottom-end that pulls into a very hard-hitting midrange. Both the bottom and midrange are usable, and it is easy to wind up the revs in a hurry. Top-end power is strong but short, as this pipe makes the bike rev quickly. This system also has strong overrev. All of our test riders discovered more confidence accelerating out of tight corners.
Overall score: 97.5Two Brothers Racing
m7
Suzuki RM-Z450
Price: $699.98
Contact: 800/211-2767; www.twobros.com
Material: Polished titanium with a billet-aluminum end-cap
Style: Full three-piece system
Fit: Bolted right on in minutes. It features a very trick mounting system. The midpipe bolts to the canister. All the hardware is included, as well as an Allen wrench.Weight: 5.00 lb
Sound: 100.5 dB
On the track: The M7 is super-snappy, offers tons of bottom-end that pulls hard and fast into the midrange. The power is instant with a stab at the clutch. The top-end spits out a quick surge of power before bumping the rev-limiter. This pipe is an extremely quick-revving, aggressive exhaust system; our pro and intermediate-level test riders loved it!
Overall score: 98.oHonda CRF45OR
Price: $895.95
Contact: 714/692-3404; www.whitebrothers.com
Material: Titanium head and midpipe with a carbon-fiber canister
Style: Full two-piece system
Fit: The Carbon Pro bolts on in just minutes using the stock hardware.
Weight: 5.10 lb
Sound: 102.1 dB (FAILED)
On the track: Off the bottom, the White Brothers system hits hard-almost too hard. The power carries into a very strong midrange that allows you to get away with less shifting. Top-end power pulls strong and can be revved out much further than the stock system. Overall, it pulls much harder everywhere compared with stock.
Overall score: 98.5White Brothers
Carbon pro
Suzuki RM-Z450
Price: $895.95
Contact: 714/692-3404; www.whitebrothers.com
Material: Titanium head and midpipe with a carbon-fiber canister
Style: Full two-piece system
Fit: Bolts on with ease in minutes using the stock hardware.Weight: 4.99 lb
Sound: 102.1 dB (FAILED)
On the track: This system has it all, including strong power from the bottom that pulls hard all the way through the top-end. Similar to the Two Brothers unit, this one is super-aggressive as the power comes on instantly. It worked the best in high-speed sections as the power pulls and never really signs off. This setup really opened up third and fourth gears with as much roll-on power as could be lugged or revved; great power characteristics for all levels of riding.
Overall score: 99.oHonda CRF45OR
Price: $795.95
Contact: 909/628-4722; www.yoshimura-rd.com
Material: Full titanium
Style: Full two-piece system
Fit: The Yosh system bolts on in just minutes using the stock hardware.
Weight: 6.30 lb
Sound: 101.1 Db
On the track: Off idle, the power is more usable and carries over to a very mellow-but consistent-midrange. The top-end pulls longer and stronger than the stock system. The Yosh system has a linear feel, requiring a bit of clutch to keep the revs up. Riders who like to rev their bike to the moon will love this system, as it seems to rev out super far.
Overall score: 94.OYoshimura
Trc pro-series
Suzuki RM-Z450
Price: $795.95
Contact: 909/628-4722; www.yoshimura-rd.com
Material: Full titanium
Style: Full two-piece system
Fit: Bolts on with ease in minutes using the stock hardware.
Weight: 6.20 lb
Sound: 100.2 dB
On the track: The Yosh setup offered more bottom and midrange with much more-usable roll-on power. We were able to wring out second gear much longer, most noticeably when accelerating out of tight corners. Top-end also has good, solid, usable power that pulls much longer than the stock system.
Overall score: 98.O