CRF450 VS. YZF450


On the ATVA Grand National Motocross circuit, there are two premier classes to choose from; Pro and Pro Production. For the last five years or so the Pro class has been full of one-off fully custom-built quads costing upwards of twenty-five thousand dollars. Although the number of entries at national events has been growing for the last couple of seasons, the ATVA wanted to develop a new class to help cut down the cost of racing and also attract series support from the manufacturers.

The new class that was developed is called Pro Production. Basically, the new class limits racers to only using production (stock) frames and the motors that come with them. Before the 2003 season, nearly every Pro rider was using an aftermarket frame (loosely based on the 250R) with some sort of motorcycle engine in it. The reason was that until recently there weren’t any quads with light enough or powerful enough engines that were competitive for racing. And the old 250R chassis that everyone favored are becoming used up and scarce.

In the new Pro Production class, racers are still allowed to uses aftermarket swingarms, A-arms, steering stems, shocks and any other part they needed. The frames can be reinforced and the engines can be modified but must remain under 450cc. However, that number may change for next year and for now the class is open to four strokes only.

Pro machines can use any two-stroke engine under 265cc or under 440cc for a four-stroke. As far as frames go, the rule is open as long as the quad is less than 50 inches wide.

With the introduction of new sportier quads like the Z400, YFZ450 and the TRX450R, we wanted to rate and compare their racing potential. To help us with this challenge, we called upon Lonestar Racing in Phoenix, Arizona. Lonestar has been building components and complete race quads for competitors on the national scene for over a decade now.

For our comparison, they sent out two top of the line machines set up for the different classes. One was the brand new production-based Yamaha YFZ450 race quad they prepared for Kory Ellis. Yes, they actually let us ride the same quad Kory won the Loretta Lynn’s National on. John Natalie, Tavis Cain, Jason Dunkleberger, and Harold Goodman are all riding new YFZs in the Pro Production class as well. The other quad was hand-built using a completely custom frame powered by one of the hottest dirt bike motors on the planet, the Honda CRF450. Lonestar uses this quad as a test machine to try out new parts in a racing environment and as a sales tool to display the latest parts they sell.

Starting with the $6899 suggested retail price of the YFZ450, Lonestar (LSR) outfitted Kory’s quad with an array of quality aftermarket parts to mostly improve handling, durability, and safety. To get the Yamaha up to the maximum width they installed LSR DC-4 plus two A-arms ($838) and longer LSR tie rods w/ends ($200). LSR wheel hubs ($307) were also mounted up to give the machine a Honda wheel bolt pattern. A one-inch forward LSR steering stem ($385) was also installed upfront so the quad would accept the popular oversized bars.

On the back end, Kory’s race quad has an LSR Axcaliber axle ($410), LSR locknuts ($105), LSR sprocket hub ($135), LSR swingarm and hub assembly ($977). LSR also changed out the stock brake lines for a set of their steel-braided lines.

Kory’s other sponsor Yamaha’s GYTR line outfitted the machine with a complete exhaust system and air filter. PEP rebuilt the stock YFZ rear shock and installed a dual-rate zero preload spring setup ($700). On the front, $1650 was spent on the PEP shocks. Kenda tires mounted on Douglas wheels get the power to the ground on Kory’s racer. So, if you collect your coupons, and send in those resumes, you can get into a full race-ready Pro Production quad for just over ten grand.

To hand-build a complete Pro race quad from scratch is a different story. For the CRF powered racer, the staff at LSR had to spend the same $3000-$4000 on the suspension components, build a frame ($2683), acquire bodywork, get 250R mounting hardware, a chain, sprockets, radiator, airbox, all the brake components, a Clark gas tank, all the controls, tires, and wheels. After all that, the machine cost upwards of twenty grand and doesn’t even run, because there is no motor.

For this project, LSR’s Jack Bedner purchased a 2003 Honda CRF450 dirtbike and removed the motor, carb and electrical system. Then he turned around and sold the powerless bike for parts. So, just to find power for the Pro race quad, it cost $3500. To build a complete quad like this one would set you back just under twenty-five thousand dollars. Holy cow!

For the track test, we took both machines to the new Lake Elsinore MX Park in Southern California. The track is a tight course with small to medium-sized jumps, a whoop section with fairly slick corners, and soft loamy berms. We had three test riders do several five-lap sessions on both machines and give us their feedback.
In the power department, the consensus was that the Yamaha had better midrange pull after the quad was through the corners and the Pro Class Honda quad could drive through the corners better with more bottom-end torque. Once out of the corners, the Honda’s shifter was harder to reach than the Yamahas. That is to be expected since this CRF engine wasn’t designed to be used in a quad chassis. It should be noted that today’s four strokes are very competitive without much investment. The old 250R and the Z400 motors take a substantial cubic dollar investment to make them competitive and race-worthy.

As far as handling goes, Kory’s quad is set up very low, about four inches off the ground with the rider on it. It handled like a go-kart. You could round any corner with ease by just giving a little input to the bars. In rough corners, it would dance across the bumps as it powered along. The Honda powered Pro quad wanted to drive through the corner sticking to the ground more. It had a slightly more comfortable controllable ride.

Over the jumps, both machines were equally good. However, the Pro Class quad tended to jump with the nose a little high. Both of them landed like they were jumping on to a firm yet comfortable pillow. Each machine weighs around 370 pounds and the wheel-travel numbers are between 10-11 inch front and rear. The only difference is that the Lonestar no-link system is slightly more adjustable than the Yamaha’s linkage setup.

Lap times were too close to call. The differences were in the tenths of seconds and didn’t tell us a thing. The real question is how strong and reliable is the stock Yamaha chassis? Will it hold up to the heavy abuse today’s pro riders dish out? From almost a year of experience, we know the 2003 Suzuki Z400 frame was not up to the task. Lonestar’s $2683 chassis has been proven to withstand abuse for years now. However, with the introduction of a new breed of sport quads, the handling advantages may be decreasing.

From what we could tell, the major difference between today’s Pro and Pro Production race quads is the price, with only a little speculation on the durability of the stock frame. So could you race a Pro Production quad in the Pro Class? Kory Ellis did it on this very quad and finished an impressive fourth at Lorreta Lynn’s. For our money, we would rather spend the ten grand plus for the Pro Production quad and save the fifteen thousand to buy a new truck to haul it in.