2006 Yamaha Raptor 700R ATV Exhaust Pipe Shootout

By our third date with Yamaha's reincarnated 700R, we couldn't wait to discover more horsepower in the new Raptor via a bolt-on or plug-in product. Just the thought of how the motor would respond with an aftermarket exhaust system attached caused us to eagerly jump into the whirlpool of testing to find out. Since this was our (and most of the pipe companies') first foray into the world of Electronic Fuel Injection, we were really curious to see how much of an advantage new metal could provide or if simply messing with the electronics would be the trick.

The process was educational for all involved, and the learning will no doubt continue as EFI becomes more common on sport quads. Replacing the fixed-ratio carburetor with a digitally controlled air and fuel mixer has made life simpler and more complex at the same time--just as with all the other technological innovations we continue to implement into our daily routines.

The Raptor's Yamaha Fuel Injection (YFI) controller does an amazing job of keeping the air-to-fuel mix accurate regardless of altitude, throttle position or what exhaust is mounted. However, in the quest for more ponies, a problem is born: The rider may demand a stronger mix than the factory-set curve provides.

DynoJet, Techlusion/Dobeck (CT and HMF) and White Brothers have already jumped on the wagon and created little black boxes that plug into the throttle body wiring to allow different fuel-air mixtures to be supplied to the engine along with different performance parameters. This is the more complex part of new technology--the seemingly endless variations to fiddle with instead of the fixed jet tolerances. We left the EFI controller tweaking to the pipe companies and simply plugged in what they gave us so we wouldn't end up with a performance that didn't match their ideal--after all, that is part of the reason you are paying the big bucks for the hardware or software. But with a manual and some time on your hands, you could certainly try a host of variations--much like trying different settings on your shocks after you get the suspension back from the shop.

After a week of mounting and yanking off hot pipes (which gives an all-new meaning for "piping hot"), dismantling the 700R to deal with the TFI units and earning a few burned digits, hands and forearms (to justify the occasional burst of swearing) in the process, our poor machine was almost as tired-looking as we felt. Our testing took us to K&N to use its dynamometer to get the horsepower output with each unit, and then it was off to a couple of tracks to uncover the riding performance characteristics of each system in the dirt. Why a motocross track instead of a trail if this isn't an MX ATV? A track means a controlled environment where we could run each system over the exact same terrain in a close-by setting that allowed for quick troubleshooting should anything break. We ended the whole process with ChemHelp's Chris Real conducting an SAE J1287 sound test. Real's no-nonsense scientific approach leaves scant room for any kind of error or questioning. The noise issue is critical, and we can't ask you to run quiet systems on your machines if we don't do the same here. Since the primary purpose of the Raptor is usage on trails, we told the companies that all of the exhausts must be under 96 decibels and equipped with a spark arrestor. That number is the law here in California and is likely to be the rule where you live in the near future. Some states have even lower sound tolerance, and the dunes in Oregon require a sub-93-decibel level. Sadly, we had three systems go over the limit, with two just barely missing the mark and one making a major infraction.

Enough background info, on to the experiment. After our baseline runs, with and without the airbox lid, we installed a high-flow K&N air filter. Our first surprise of this entire escapade was the single horsepower gained by simply removing the airbox lid and further compounded by the high-flow kit's three-pony increase. Since it couldn't hurt any of the exhausts, we left the K&N in place for all of the systems. We also sampled Pro-Tec's MoFlow Airbox Lid, which functions as a prefilter and keeps the occasional splash off the filter--good for a paper filter such as the K&N. The MoFlow didn't alter the power, and it's a good option versus running a bare filter.

For each system we produced a dyno chart, a brief description of the test riders' impressions along with the actual sound level emitted by each. As you will no doubt notice, adding a pipe gives the new Yamie a boost but nowhere near what it did for the old 660R. In fact, it was a hair-splitting job to separate the wheat from the chaff, with all of these systems falling within a two horsepower and torque range. The jury is still out on whether the new engine is simply that good; the YFI keeps a tight rein on things even with aftermarket electronics in the mix. Using the same technology in a different wrapper could also be the culprit.