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Embracing the Beast
A first date with the 2004 Yamaha R1
by evans brasfield
Monday, March 01, 2004

When new model season comes around, sportbike enthusiasts look forward to the nearly endless series of track tests featured in print and on the web. Bench racers and spec sheet jockeys can play fantasy racing series over their double lattes while the snow melts outside. So, why are these stories so important? First, by wining and dining motojournalists in foreign lands adjacent to world class tracks, the manufacturers definitely put writers in a good frame of mind when considering a new motorcycle. Second, those same writers get to remind us, once again, how they exist in a plane above us with the demigods of motorcycling. (OK, so I'm a little bitter that I didn't get to go to Australia for the on track introduction....) Well, the funny thing is, the vast majority of sportbikes sold in the United States never turn a wheel in anger - or even pleasure - on a closed course. So, despite the fact that I didn't get to add another track to my collection, getting to know a sportbike on the street can give a pretty accurate impression of what us mere mortals can expect from a bike.

My first recollection of the original R1 has nothing to do with a track at all. In fact, when I think back to the first time I saw it, I visualize it being wheeled out of the freight elevator on the fifth floor of the office building where I worked. The sexy new bike was parked in the conference room, and the tech briefing began. The Yamaha PR people really knew how to tease us since we wouldn't get a chance to ride the R1 for months.

Think back to 1998. Big bore sportbikes were, well, big. The only motorcycles that could claim the profile of a middleweight with liter-class displacement were a few Frankenbikes that had big engines shoehorned into little frames. Yamaha changed all that with the R1: small profile, 1000cc engine, and in-your-face styling that was certain to get you sent to the principal's office. The R1 also brought some sportbike features that have now become pretty standard across the board to the public. Remember the big deal about the long swingarm that was made possible by stacking the transmission above the crank? Well, that's pretty common now. Then there was the power-to-weight ratio that turned the class on its ear. To make the bike even more desirable, the 1998 R1 was imported in relatively limited numbers. All you needed for rock star status at your local gathering place was to show up on the much desired R1.

The 2004 R1 continues Yamaha's relentless refinement of an already great package - this time with another of its biennial complete makeovers. Although past emphasis in developing the R1 had the street primarily in mind, 2004 has revealed an increased focus on the track. Perhaps the most noticeable change to the R1 - aside from the sexy bodywork and under tail exhaust - is the new frame. The main spars are almost three inches narrower than last year. Instead of spreading around the outside of the engine, the spars go over the engine. While depending less on the engine as a stressed member, the frame delivers increased rigidity to the tune of 200 percent on vertical, 30 percent torsional, and 50 percent from the side. Although it looks larger than last year, the sub-frame uses Yamaha's Controlled Flow (CF) technology to be both lighter and stronger than last years. CF casting is also responsible for the ultra-sexy swingarm. The underside bracing looks as strong as the 30 percent increase in both torsional and side force rigidity indicates it is.

Clamping a pair of 43mm Kayaba forks, the 04 R1's triple clamp utilizes 6mm less trail (97mm) and the same 24 degree rake as last year. According to Yamaha, the goal of this geometry change is better turn in and a more solid feel. A speed sensitive steering damper helps keep the front end from getting frenetic at speed. However, neither the change in geometry nor the narrower frame would have been possible without tilting the engine forward 10 degrees for a new lean of 40 degrees. The new engine position helped shift the R1's weight bias to 52 percent on the front wheel versus 50.5 percent last year. Aside from the obvious handling benefits precipitated by the new engine angle, the riding position was opened up for the rider without compromising ground clearance. The new peg position is 2.5mm forward and 7.5mm lower than last year. The grips were also moved 10mm higher for improved rider comfort.

When you twist that throttle grip, some new things happen with the 2004 R1. The throttle cables control a set of butterfly valves in 5mm larger throats. A secondary set of butterflies controlled by the Engine Control Unit (ECU) endeavor to keep the throttle transitions as silky smooth as they were last year with the vacuum slides. To handle this all important duty, the ECU was upgraded from a 16 bit to a 32 bit processor - all while being slightly smaller and lighter than last year. Of course, a pair of throttle position sensors (TPS) are used to track the two sets of throttle valves. Controlling air flow isn't the only way to smooth throttle transitions, though. Long nosed injectors located closer to the throttle bodies at a steeper angle to give the fuel more time to atomize before entering the cylinders.

The air rushing past the butterflies gets the push that horsepower junkies have been requesting for years. For 2004, the R1 finally receives the factory ram air treatment. If you take a gander at the fairing just below the headlights, you'll see the air ducts that channel the pressurized air through the frame and air filter into the 5.9L airbox. A nice side benefit of the new intake is a meaty intake honk as you crank on the throttle. On the other end of the atmospheric flow, the R1's titanium exhaust system unleashes a growl that you might never expect from a stock bike. The extended effort Yamaha engineers put into the exhaust note is sure to be a hit with every rider who doesn't reflexively replace the OE system. With the exception of the stainless steel catalyst container, the entire exhaust - even the EXUP valve - is titanium.

Still, the engine's internals are where all the magic takes place. Aside from the obvious changes necesitated by the engine's increased forward lean, the top end received more than a token going over. Exhaust and intake ports increased by 0.5mm while still allowing for a tigher valve angle. To save valve weight, the intake valves were shortened 3.5mm and the exhaust valves are 1.5mm shorter. To accomodate the new port size, all five valves grew 0.5mm in diameter. The combustion chamber became more compact thanks to both the tighter valve and a shape change in the cylinder dome. The new squish area yields a 12.4:1 compression ratio (up from 11.8:1 in 2003). Increased intake cam lift is intended to improve acceleration, while reducing the exhaust cam lift and both cam journal diameters (for a 4 percent weight savings) helps to reduce mechanical power loss. The timing chain and cams are kept in sync with a new hydraulic cam chain tensioner.

Since the 2004 R1's rev limit has been bumped up 2000 rpm to 13750 rpm, the pistons were lightened three percent. Still, the men in lab coats managed to increase the piston diameter to 77mm and shorten skirt height at the same time. To increase the strength of the piston near the pin ribs were added. The new piston diameter makes the R1's 77mm x 53.6mm bore and stroke even more oversquare than last year's 74.0mm x 58.0mm figures. Do you think Yamaha wants the new R1 to rev quicker?

This years connecting rods are shorter and lighter. The big ends feature fracture split caps. The result of actually breaking the cap off of the con-rod's big end is a more precise fit between the cap and rod. Consequently, the roundness of the big end is enhanced. Also, the cap bolts now attach directly to the rod itself for a nine percent weight savings. A new crank design reduces weight by 16 percent. The entire crank assembly is 23.7mm shorter to help make the engine narrower.
 

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When the R1's engine played a larger part in the chassis rigidity, Yamaha cast the sleeveless cylinders into the top half of the crankcase. The 04's beefier frame allows for the cylinder block to become a separate entity again. The upside is cylinders that are 4mm closer together without compromising cooling. The new block's closed deck design allows for better ring sealing by improving the block's rigidity, allowing the cylinder bores to better hold their shape during high rpm operation.

The power generated by this higher revving, quicker spinning engine gets channeled through a new, smaller diameter clutch assembly. In fact, the width of the clutch basket may actually be the only thing affecting the engine's overall width that didn't get reduced. Instead, Yamaha added an additional friction and steel plate. Good ol' coiled springs replace the diaphragm of previous models for better feel. Last year's cork friction plate material was swapped with paper based material for the same reason.

You'll need that additional feel since the taller first gear will require more slipping to get the bike under way. The 04 R1's transmission cogs are of a close ratio design to keep the rpm from dropping from gear to gear. Consequently, the R1 is mathematically capable of hitting 98.8 mph in first gear! At the press briefing, one Yamaha rep boasted that "This will be the best shifting Yamaha you've ever ridden." And he was right. The R1 loves high rpm clutchless upshifts. No muss, no fuss.

So, what the cool new frame keeps from sitting on the ground is a lighter, narrower, more powerful, smoother shifting, bellowing beast of an engine. All you need to do is hear the engine when it's started to know that it will kick some serious butt.

Throwing a leg over the R1 brings the new riding position into the foreground. While still decidedly sporting, the lower pegs and higher grips do unfold the rider a bit. The next surprise is how narrow the tank is between your knees. With the fuel load carried in the rear portion of the tank while the front half of the two-piece "tank" is really the airbox cover.

When getting under way, the tall first gear requires some throttle. Nursing the R1 around at parking lot speeds, will find you working the clutch a little. The new steering damper is completely unobtrusive at low speeds. A damper ball allows fluid to pass by unobstructed at low steering speeds. Get the R1 to wag its bars, and the check ball forces the fluid to pass through the damper, slowing handle bar movement.

Out on the road, the new steering geometry lets the R1 turn in quickly. Changing lines is also as easy as giving a slight steering input. With the new emphasis on track duty, the suspension is noticeably firmer than last year. While you do feel more of the pavement irregularities, the effect isn't overbearing. However, dive into a bumpy corner at speed, and you'll appreciate the stability the chassis offers. The route that Yamaha had planned for the introduction covered all kinds of pavement - from putting green smooth to gnarled mountain asphalt - and the R1 devoured all of it. Of course, the Dunlop D218 tires deserve some of the credit. In conditions ranging from early morning cold or rain dampened to warm and dry, the D218s were nothing short of superb. They held onto the road - no matter the speed - and if I got a little energetic with the throttle exiting a corner, the back end would casually start inching its way outward before smoothly moving back in line down the straight.

The R1's throttle response is almost everything the PR folks said it would be. In fact, most of the time in on- and off-throttle transitions you won't be aware that the ECU and the secondary butterflies are at work (and not a set of CV slides) - which is as it should be. At low rpm, you will experience some snatchiness as you move from off-throttle to on, but that is more a function of a large displacement engine breathing through 45mm throttle bodies. Get the rpms up where they belong, and the connection from brain to wrist to power is almost seamless. At around town speeds, the R1's engine has oomph but doesn't feel like anything worth writing home about. However, getting clear of traffic and opening the throttle changes things.

Power begins to build noticeably at about 6000 rpm, but the party really starts at 8,000 and carries all the way to just before the 13,750 rpm rev limit. While Yamaha claims 180 hp at the crank with an assist from ram air, the R1's power delivery coupled with the close ratio gearbox helps to generate speed at a dizzying rate. In one several mile straight across a valley, I saw numbers on the speedometer that would land me in divorce court if I mentioned them. My riding partner, however, had no such compunctions and continued on to press up against the R1's speed limiter - at an indicated 189 mph. He said that the engine never felt it was being restricted in a heavy-handed way, but the bike simply wouldn't go any faster. A quick trip to the pocket calculator reveals that 189 mph is roughly 300 kph where the speed restrictors on other bikes kick in, too.
 

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Fortunately, the R1's brakes are more than up to the task of converting movement into heat. Radial mount calipers not only look cool, but also virtually eliminate flex under hard braking. Powered by a radial pump style Brembo master cylinder the binders grip 320mm front rotors (up from 298mm) that are 0.5mm thinner than last year in order to retain the same weight. The progressive action of the brakes does an admirable job of hauling the R1 down from speed, delivering consistent stopping at a variety of lever pressures without, not surprisingly, a single sign of fade. Trail braking into a corner is a simple activity. Just what you'd expect from a bike destined for both the canyons and the race track.

So, at the end of a day of hard riding, the verdict on the 2004 R1 is quite positive. As a street bike, it offers power, handling, and exceptional styling. As the tire tests for the AMA Superstock series have shown, the R1 looks to be a force to be reckoned with on the race track, too. With the bevy of new open classers in the showrooms for 2004, should you plunk down your hard earned $10,599 for a R1? Well, if you're the type of person who needs to know which bike wins the comparisons and delivers the fastest quarter mile times, you'll have to wait for the journalists to tell you which big bore sportbike is the best so that you can be confident that no one will question your choice. However, if you're the type of rider who knows what you want, go with your passion. If the R1's aggressive styling catches your eye. Go for it. The R1 can more than back up its looks.
 

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