WHAT IT IS:
The Fuel Customs intake is a complete high-flow system centered on a custom-molded intake tube that features a horsepower- and torque-building tapered design. The custom intake tube is coupled with Fuel Customs’ oversized fabric air filter and a free-flowing airbox. For the fuel-injected YFZ450R/X, Fuel Customs offers the intake system with or without the airbox. Fuel Customs makes a better-flowing intake system for nearly every popular sport quad.
The custom intake tube is tuned for maximum horsepower and torque and improved throttle response, then molded out of a rigid plastic that won’t flex under heavy turbulence or suction. All mounting brackets are powdercoated, and Fuel Customs provides high-quality hose clamps to finish installation.
The Fuel Customs-provided filter element is an eight-ply fabric filter for increased filtering capability compared to the industry-standard, four-ply fabric filters. The highly efficient intake tube design is dyno-tuned and refined to perfection, enhancing airflow velocity and giving optimum power over the entire range. The YFZ-R system we chose included a Fuel Customs airbox for protection against mud and water.
Installing the Fuel Customs intake on our YFZ450R was pretty straightforward. It is easier to remove the rear fenders completely if you are running the airbox option. You do need to drill a ¼-inch hole through the subframe for new airbox bolts, but the provided installation instructions are very clear. After removing the fenders, you can easily remove and discard the stock airbox. After drilling two small holes, simply install the Fuel Customs intake tube and airbox loosely, then install the filter through the airbox and onto the Fuel Customs intake tube. Line everything up square, and tighten the hose clamps. The Fuel Customs intake tube will also have a port and threaded hole for you to install the air sensor.
The Fuel Customs intake is a great bolt-on performance part for any application. On a machine that is closer to stock, the intake will instantly add 1.0 to 1.5 horsepower. You can expect even more impressive gains on a built machine. If your YFZ-R has cams, porting and increased compression, you could see an increase of nearly 3 horsepower. Note, however, that it will require fuel tuning. The stock EFI system can compensate for the addition of an exhaust system, but as soon as you start increasing airflow, you are going to need a controller/programmer. With the fuel curve properly tuned, the Fuel Customs-equipped YFZ-R is noticeably faster, more responsive and powerful.
The Fuel Customs intake makes power across the board on the YFZ-R. Installation is pretty simple, and the oversized, eight-ply filter seems to be keeping our engine clean. The provided airbox is a must if you are dealing with muddy or wet conditions. We really like the way the YFZ-R pulls off the bottom with the new intake installed. If all you do is drag race, or even TT or flat track, the kit will be fine without the airbox. If you race motocross or ride off-road, we recommend the additional protection of the airbox. While riding in the dunes is typically a dry situation that would not require the airbox, the extra protection will help lengthen service intervals, so we would recommend it for serious duning as well.