MXA RETRO TEST: WE RIDE GRANT LANGSTON’S 2007 NATIONAL CHAMPIONSHIP YAMAHA YZ450F

10/04/2022 02:15 PM

We get misty-eyed sometimes thinking about past bikes we loved, as well as ones that should remain forgotten. We take you on a trip down memory lane with bike tests that got filed away and disregarded in the MXA archives. We reminisce on a piece of moto history that has been resurrected. Here is our test of Grant Langston’s 2007 National Championship Yamaha YZ450F (which was a 2008 YZ450F), just as it ran back in 2007). Manufacturers field race teams for one reason and one reason only—to sell bikes. If a race team wins races but bikes don’t sell, there is something rotten in Denmark. If the race teams loses, but the bikes sell like hot cakes, everything is peachy-keen.  In 2007, Grant Langston was a marketing man’s dream rider. Not only did he win the AMA 450 National Championship, he took pains at every step along the way to praise the brand-new 2008 YZ450F he raced in the 2007 series. Grant switched over to the 2008 model with six races to go in the 2007 Championship. During these six events, Grant went 10-2-2-1-1-1. When you factor in that one of the second places came when Kevin Windham mistook the white flag for the checkered flag at Washougal (costing Grant the overall) and the other came during Ricky Carmichael’s triumphant last-ever AMA National at Millville, Grant was as close to perfect as a rider could be in a tight title chase.  For Yamaha, it was kismet that the release of the new bike resulted in a turnaround for Grant’s season, enthusiastic endorsements by their star rider and a season-capping National Championship (Yamaha’s first motocross title in nine years).   The only thing missing to make the picture perfect was outside confirmation that Grant’s 2008 Yamaha YZ450F was as advertised. That is where the MXA wrecking crew came in. We took the opportunity to ride Grant’s 2007 AMA 450 National Championship bike—a surprising ride in many ways. But, it wasn’t the first time that we had ridden Grant Langston’s bike—it was actually the fourth time. Here is the MXA/Langston list: (1) In 2003, the MXA gang tested the KTM 125SX two-stroke that Grant Langston won the AMA 125 National Championship with. (2) In 2004, we got our grubby little hands on Grant’s Paul Delaurier-tuned KTM 250SX (the one with the electronic power valve). (3) In 2007, we tested the Kawasaki KX450F that Pro Circuit had built for Grant to race in this year’s AMA National Championship (but when the funding didn’t come together, Pro Circuit released Grant to ride for Team Yamaha). (4) Grant’s 2007 Yamaha YZ450F is the subject of this test. Grant’s works Yamaha YZ450F ran the stock triple clamps and revalved stock Kayaba forks. WHAT IS IT ALL ABOUT? First and foremost, the MXA wrecking crew has never ridden a factory-backed works bike that uses as many stock parts as Grant’s YZ450F. Instead of an exotic, hand-built, one-off, Grant’s bike was a painstakingly prepared race bike that almost any YZ450F owner could replicate.  Out back Grant elected to run a works shock with a 53 N/m spring, but it was connected to a stock shock linkage WHAT PARTS ARE WORKS? Grant’s bike may be the stockest of all the works bike we have ever tested, but it did have works parts. Here is the list: Magnesium hubs from YMC (Yamaha Japan works parts), titanium axles, Ti linkage bolts, titanium hardware, works KYB shock, oil cooler designed by YMUS (Yamaha USA), 1.5 liter-larger aluminum gas tank and in-house cylinder head porting, a high-compression piston and torque cam. WHAT PARTS ARE PRODUCTION? The list of production parts that Grant uses is impressive. It includes the stock 48mm Kayaba forks (although the internals are re-valved), triple clamps (with the stock 25mm offset), shock linkage, chassis (not even the subframe is touched), clutch (although the clutch basket and clutch cover come from Yamaha’s GYTR product line), Keihin FCR carb (it has been bored out to 41mm) and spokes.  For oil cooling, Yamaha welded oil tanks to the bottom of the radiators. COULD YOU BUY GRANT LANGSTON’S YZ450F? Yes. In essence, Grant Langston won the National Championship on a bike that has about the same work done on it as the typical AMA privateer’s bike. Apart from the mag hubs and works shock, it is a stock YZ450F with re-valved forks, engine work, a White Brothers exhaust pipe, ProTaper bars, a Uni air filter, Tag grips, ARC levers and lots of loving care.  WHAT ARE THE TRICKEST PARTS OF LANGSTON’S BIKE? Grant’s bike has a few pieces of exotica that Team Yamaha fabricated for the South African. Most obvious to the MXA test riders were the 15mm higher footpegs (borrowed from Doug Henry’s Grave’s Motorsport’s Supermoto bike). Less obvious is the fact that one peg is 3mm higher than the other (because of a broken femur that Grant suffered years ago). Grant runs 15mm taller bar mounts but mates them to rather low Ricky Carmichael-bend ProTaper bars for an almost negligible gain. Team Yamaha cuts the fuel petcock off of Grant’s bike to eliminate the chance of the gas being turned off by accident (they turn it on with pliers). As with almost every AMA National works bike, Langston’s YZ450F has an oil cooler. The oil cooler uses a Pro Circuit oil pump that circulates the hot oil into a catch tank welded to the bottom of the left radiator. It is not an air-cooled oil cooler but more of a heat-sink cooling tank. Langston also uses one radiator from a WR450F because it is larger. The last piece of trickery, which many YZ426F owners will be familiar with, is the wet-sump engine, which only uses the oil that is contained in the engine cases (no external oil tank). Grant’s White Brothers Ti-Pro exhaust system has a stepped head pipe. A replica will be made available to the public. Grant Langston’s 2007 AMA 450 Championship YZ450F did have Yamaha works parts, but it was the most production-based machine to ever win an AMA title. TEST RIDE: HANG ON AND PRAY The MXA wrecking crew got to ride Grant’s bike just as it rolled off the track after the Glen Helen National. It had been cleaned up but not changed.  HOW FAST IS IT? Without a doubt, Grant Langston’s YZ450F is the easiest to ride National bike we have ever tried. It produced a lot of horsepower, but Grant’s preference for bottom to mid power meant that all you had to do was roll the throttle on a millimeter to get the bike moving. There was no need to rev Grant’s engine. MXA test riders could ride it hard through a corner in second gear or lug it around the same bend in third gear. Grant runs a 50- or 51-tooth rear sprocket (stock is a 49). The low gearing makes second gear feel like a very broad first gear and turns third into the gear of choice. The transmission is a stocker (no special gear ratios). This bike had a lot of grunt. The power was so pleasant that doing hot laps was almost casual. No wonder Grant produced so many come-from-behind wins at the end of the season. His bike wasn’t wearing him out. How fast is it? It is not as fast as some of the powerhouse bikes that Grant raced against, but it puts every iota of power into the ground. It doesn’t waste any energy. HOW WERE THE BIKE’S  ERGONOMICS? Grant’s setup is fine-tuned for his personal tastes. The most noticeable peccadilloes are the very high footpegs. Every short MXA test rider thought that these were the cat’s meow. The tall pegs made the bike feel lower and worked well with Grant’s choice of bars. Unfortunately, tall test riders felt cramped by Grant’s miniature cockpit. The clutch and brake lever positions were raised from the old-school position, but not objectionably. The only concession to crashing was an ARC folding lever on the clutch perch. The perch itself was a GYTR part with a left-side hot start.  DOES GRANT’S YZ450F TURN? Yes (thanks to careful prep). Grant has tested more triple clamp offset combinations than anyone in the world. When the MXA wrecking was testing five different YZ450F offsets at Glen Helen a couple months ago, Grant kept coming over to see how our results compared to his. In the end, Grant’s bike turned as well as any YZ450F we have ever ridden. Here are the steps Grant took to make his YZ450F turn at the optimum end of the spectrum: (1) Grant’s bike uses the stock 25mm offset triple clamps and 48mm fork legs. (2) By sliding his rear wheel all the way back in the axle blocks, Grant puts more weight on the front wheel. (3) Grant stresses the need for the best front tire possible. Luckily, Grant has access to Bridgestone works tires. (4) By adjusting the fork height for track conditions, it is possible to change the head angle slightly for the traits most desired. (5) The incredibly torquey and responsive low-to-mid powerband makes Grant’s YZ450F much more responsive to “throttle steer” than a normal powerband. The slightest burp of power at mid-turn induces a torque reaction that tucks the front wheel and steps the rear out a couple inches.  HOW WAS THE WORKS SUSPENSION? Unlike most factory riders, Grant Langston does not buy into the “works forks” propaganda. He tried Kayaba’s works forks earlier in the year but didn’t like the oversize fork tubes and stanchions. Why not? Grant felt they were too stiff. Not too firm in motion, but too stiff for the YZ450F chassis. Grant elected to run the stock 48mm forks. Grant feels that the stock forks feed more flex into the front end to help the YZ450F turn. As for the feel of the re-valved forks in motion, they were very stiff. As with most factory riders, Grant’s speed and willingness to hit bumps at full-tilt requires the forks to be way stiffer than mortal man would like. Grant’s works rear shock was a work of art. It was mated to the stock shock linkage and delivered a firm but stable ride. Grant’s only concession to softness was to insist that his rear axle be moved as far back in the swingarm as feasible. This increased the leverage on the shock and had the corollary effect of moving the engine forward on the weight bias chart.  Grant Langston was losing the 2007 AMA 450 National Championship until he switched to the 2008 YZ450F with six races to go. VERDICT: WHAT DO WE THINK? Take our word for it: most works bikes are pie-in-the-sky dream machines. They are so fast, so stiff and so finicky that they would be too demanding for the Average Joe. We’d all love to have one but probably wouldn’t live happily ever after with it. Not so with Grant Langston’s National Championship-winning YZ450F. Anyone from a Novice to a National Champion could successfully race Grant’s bike (with a few adjustments for stiffness and cockpit height).   The post MXA RETRO TEST: WE RIDE GRANT LANGSTON’S 2007 NATIONAL CHAMPIONSHIP YAMAHA YZ450F appeared first on Motocross Action Magazine.