Photography by Kevin Wing
What do Yamaha, Chuck Graves, the AMA Formula Extreme class and Damon “Bucky” Buckmaster all have in common? Yamaha’s flagship sportbike, the YZF-R1. Introduced in 1998 to a world motorcycle audience accustomed to Honda’s dominance in the liter class with the light and lithe CBR900RR, journalists were left slack-jawed by the R1’s performance. It became the canyon-carving tool of choice among Sunday apex strafers, and it often happened to be a racer’s championship-chasing tool. As eye candy, it was Japan’s best and brightest – only the Ducati 916 was sexier.
Chuck Graves races open-class motorcycles, and when the R1 came along, he grabbed one, making his own performance parts to boost the standard R1’s performance to championship-winning levels in the cutthroat arena of the racetrack. He has collected multiple class championships on his R1 at Willow Springs Raceway and set fastest qualifying time for the first Willow Springs Toyota 200, a time eventually bested only by factory riders Steve Rapp and Jake Zemke. Graves’ performance parts building expanded from bits just for his bike to a full-blown aftermarket business, which now also works closely with the Yamaha factory effort in the AMA Formula Extreme and 600 Supersport classes.
The Graves Yamaha Formula Extreme R1 motorcycle is unmistakably an R1, although there are precious few parts left untouched by the Graves crew. At the heart of the machine lives the 998cc engine. The stock outward appearance belies all the trickness within. Capacity remains the same as the street engine, but everything from under the cam cover down to the sump plug has received the necessary attention to produce the ‘official’ quote of 175 or so horsepower. Specific power output remains a “Graves family secret”.
The usual hotrodding techniques have been applied – cam lift, duration and timing, flowed and ported cylinder head, forged pistons bump compression ratio to 13.5:1 and are connected to suitably stronger Carillo connecting rods. A massaged crankshaft transmits power to the rear wheel via a Yamaha Engineering Corporation (think HRC-style skunk works) close ratio transmission, and Graves’ own mechanical-style slipper clutch, which helps keep engine braking from causing the rear tire to skid/chatter on corner entry, allowing the rider to more quickly select the necessary lower gear and carry more corner entry speed without upsetting the motorcycle.
Feeding an engine with such a voracious appetite for oxygen and high octane fuel is the duty of an intake system consisting of a larger, carbon fiber ram air box of Graves design, and a choice of either 41mm Keihin flat-slide carburetors, or 40mm throttle bodies working through a Dynojet Power Commander when the rider opts for the fuel injection system. Riders report more feel and feedback from the old school carbs when finding traction at the limit. Seems the fuel injection is “too smooth” in certain situations for the rider to know exactly what the rear tire is doing while at the edge. Development of the fuel injection goes on, however, and will likely see the carbs encased in an acrylic cube on Chuck’s desk someday. Ushering out the hot exhaust gasses is a Graves titanium thing of beauty that puts out not as much volume as you might think. Keeping it all cool is a massive aluminum radiator (don’t ask if you can have one, because you can’t . . . it’s a kit part taken from the now dormant R7 superbike).
Harnessing the engine’s massive power is the job of the R1 chassis and suspension. Graves talks highly of the standard R1 chassis, stating that they’re strong, and just as important, straight. Regardless, it gets a thorough going over to add strength front to rear and adjustability (12mm vertical/8mm fore & aft) is built in at the swingarm pivot, along with Graves’ adjustable triple clamps at the steering head. Connecting rear wheel to the frame is handled by the one-off swingarm. This is one item that Graves was somewhat vague about, both in specification and origin. Suffice to say that it’s his and you can’t have it.
Ohlins, superbike-spec suspension graces both ends of the bike, with a 43mm fork up front, and provides adjustability that I haven’t the slightest idea how to use. The team carries all the necessary components to make suitable tweaks to help shave another tenth of a second or two off of a lap time. Potentiometers on the fork and shock record suspension movement information for post ride downloading and analysis; along with other machine conditions that get recorded and downloaded from the Drack data acquisition system.
All is not WFO, however. Brakes are a roadracer’s best friend at the end of a straight. Out back, a small, two-piston Nissin caliper clamps down on a full floating rotor. Judging by the rotor’s coloring, I’d say that it gets a real workout. The front calipers are the radially mounted variety from Brembo, with TiNitride coated pistons, which have holes drilled in them near the pad for more effective cooling. Full-floating Brembo rotors of 305mm diameter are on Damon’s bike, after testing 320s and 295s. Damon vividly remembers testing the smallest rotors (although it isn’t a fond memory). Size does matter, but it isn’t everything
In this day of 320, and even 330mm rotors, 305mm seemed to me an unlikely selection, given the relative weight of the bike and the speeds achieved. Damon explained that brake power with the 305s, and the particular pad compound he uses, is more than enough for his style (Hacking uses 320s), and the smaller rotor diameter makes turning the bike easier. This explanation figures in again when you see 16.5″ rims instead of 17 inchers like the street R1. More tire on the ground at full lean is another reason for using the 16.5ers.
Much like a 5-year-old who has just overdosed on Halloween candy, the specs of Graves’ bike had my brain buzzing, and I had so many more questions to ask I was ready to burst! But Chuck and company had told all they were going to tell, which meant the time had come to ride. A ‘triple-threat’ of facts became prominent in my mind, including (1) 175+ h.p. (2) $80K replacement value (think crash and burn), and (3) crashing ends the party for everyone. Oh my…….
Brad Banister, Yamaha’s PR man, could also see the potential for disaster by letting us have a go on the FX bike without a warmup session or three. Just so happens, three R1s were brought out for the occasion, one completely stock, while the other two sported GYT-R accessories in the form of slip-ons (carbon fiber and titanium), footpegs, and carbon fiber pieces here and there. After a random drawing to determine the order in which we’d ride the FX bike, we began our rotation on the street R1s to get in the groove. This gave me a chance to regain a familiarity with the track, and get my head in the game. After downloading the previous rider’s info from the data acquisition system, a walk-around inspection of the bike is performed, fuel level checked, etc. Chuck and his team are very thorough, professional, and leave nothing to chance.
Willy Warms Up On the GYT-R Accessorized Stock R1
I get on the bike, and Chuck gives me a quick run down on everything, concentrating on kill switch locations (one on each handlebar) and more notably the race shift pattern. I thumb the starter button, and the starter motor labors slightly against the high compression engine, but quickly brings it to life. The riding position has the rider ‘on’ the bike, rather than ‘in’ it, and you feel you’re ready to pounce. Despite its race tune, the engine is able, if not content, to idle and pulls away under the merest whiff of throttle on the way down pit road. Bulk does not describe the bike, but it certainly has a ‘presence’. There is little doubt that you’re aboard something very potent.
I spend my first lap feeling out the bike, looking for any signs that it may not tolerate the unpracticed inputs of my rookie skills. I needn’t have worried. A race bike this powerful would wear out a rider in short order, if not toss him, if it were an unmanageable handful. The Graves crew understands this, and has gone to great lengths to make sure that the rider controls the bike, and not the other way around.
The engine is a marvel of flexibility and power. It didn’t matter if I was burbling down pit lane, or shrieking to redline in each gear on the front straight, I detected no spikes or steps in the power curve. Whether treading with part throttle at the double apexes of turns 5 & 6, accelerating out of one of California Speedway’s many chicanes, or driving hard onto the front straight, the engine did only what it was asked to do, nothing more, nothing less.
The engine is aided in its exemplary manners by the 41mm Keihins. The carburetion is absolutely faultless, and seamless. Throw in whatever adjective of praise you want to use, and it applies. I have yet to sample a fuel injection system (or another carb setup) this good. Whether pulling from 5000 rpm, or holding part-throttle at 9000 rpm, there is no hitch, hiccup, or stumble. Lots of dyno time was spent dialing in the carbs, and it paid off. A Lambda sensor doesn’t hurt, either.
Brakes that have the look and reputation of the Brembo setup inspire a cautious squeeze for the uninitiated. I was one of those people. Like the engine, the awesome power they possess is made very accessible and manageable. Initial bite is not as strong as the OE setup, but there is much greater feel and a finer degree of controllability, which aids trail braking deep into the corner entry. And when you need to throw out the big anchors, just squeeze a bit harder and you’ll be rippling the asphalt with the front wheel.
The slipper clutch worked in concert with the brakes to make corner entries a less dramatic affair, allowing the rear wheel to maintain its proper track. You could feel when the clutch was performing its slip duty. The clutch lever would pulse, much like a brake lever transmitting by Braille the uneven contour of a heat-warped brake rotor.
Getting acquainted with the engine and brakes was a pretty straightforward affair for me, but the chassis presented special challenges for me, mostly because I’m specially challenged. The bike’s setup, from front to rear, is exactly as Damon rides it. My only other experience with a proper race chassis is my 125 GP bike, which, mostly by virtue of great stiffness and anorexic weight, handles extremely well.
The Graves bike had me comparing and referencing some of the sensations from my 125, which may seem ludicrous, but the similarity in feel was unmistakable, however incongruent the comparison may appear. On one hand, the FX bike exhibited the stability of a ship in dry dock, and on the other hand it changed directions with cat quickness, requiring an effort level commensurate with steering your car. Areas of the track that had the street bikes wallowing and or shaking their heads (in their defense, on stock settings) passed beneath the Graves machine as if it were new pavement, thanks to the Ohlins hardware. Undoubtedly, the adjustable swingarm pivot and steering head also play an important part in this quest for the best from the worlds of stability and agility, as do the 16.5″ Marchesini rims.
All too soon, my 5 laps aboard what is certainly the finest race machinery I’ve ever ridden came to an end. Like a gambler on a roll, all I wanted was a few more laps, because “I knew I could go a little faster if I….”, well, you get the picture. I got off the bike and compulsively asked myself “Why can’t the OEs make street bikes work like this?”
The Graves crew and their riders have worked hard together to craft an instrument that takes hyper speed and makes it feel like slow motion. Problem is, what works great in the confines of a closed course, would be sorely out of place in the no man’s land of the public realm (the street), kinda like using an unlimited hydroplane to go Bass fishing.
With the exception of the chassis and radiator, you can practically duplicate the race bike that Chuck has built, with many of the parts coming from both the Graves and Yamaha GYT-R catalogs. All you need is money.
Bucky Shows How It’s Done
