2004 Yamaha R1: More Power, Less Weight

By Gary Morello

When the 2003 R1 made its debut, the styling was aggressive, fuel injection was adopted and the power-to-weight ratio was looking better than ever.

For 2004, Yamaha went back to the drawing board with its flagship sports bike and added things like ram air for an improved top-end power output, and radial-mount forged calipers with 320mm discs up front to tighten up deceleration.

But what of the new look? Is it better than the '03 model? We've spoken to a few of the local Melbourne-based bike nuts and from this it is clear that opinion has been polarised.

Some love the new look, with R6-esque xenon headlights and the new curvy ram air ducts and underseat exhaust pipes.

Others aren't so sure the slightly more curvaceous new look is as decisive as its predecessor, one dissenter going so far as to say "It's crap. Give me a ZX-10 any day."

The newly sculpted LED brake light was needed to accommodate the twin titanium underseat system - also seen on bikes like the '04 CBR1000RR - and the slightly slinkier fairing adds a bit of style to proceedings.

A lightweight, CF (Controlled Fill) die-cast truss swingarm coupled with a fully adjustable piggyback shock absorber not only looks like the dogs bollocks, but also ensure improved power down.

From where I stand, the new look is very easy on the eyes, and I especially like the new ram air ducts, which together with a more aerodynamic fairing almost gives the R1 a jet fighter quality.

And speaking of jet fighters, the new Japanese sportsbike is the quickest R1 yet, boasting a third-generation, all-new 998cc inline 4-cylinder engine, which was tuned with lessons learned from Yamaha's M1 MotoGP bike, currently ridden by the two-wheeled wizard Valentino Rossi among others.

Using technology gleaned from its MotoGP development, the new R-bike has the litre-class category's leading power-to-weight ratio - a stunning 1kg per horsepower.

The R1's low kerb weight of 172kg combines with the ram-air assisted 1.0-litre motor, generating a very useful (claimed) 180bhp @ 12,500rpm, to achieve such the impressive power-to-weight ratio.

Those who are looking for a new hoon-mobile or wheelie bike need look no further - just don't expect those rear tyres to last long.

The 134kW liquid-cooled mill has 5-valves per cylinder, and the narrow-angle 5-valve combustion chambers make for an efficient 12.4:1 compression ratio. Together with bigger valves and intake cams (with more lift and duration) this helps increase the flow of air, making combustion more efficient.

Compared to the 2003 YZF-R1, the crankshaft is now 16-percent lighter, the forged pistons are 3-percent lighter and the 7.5mm shorter (and and 9-percent-lighter) conrods add up to a quicker-revving engine with less reciprocating mass, which Yamaha reckons leads to excellent high-rpm durability.

Other fancy engine features include high silicon-content ceramic-composite cylinder sleeves. These basically make for improved heat dissipation, as well as reduced friction and for a more consistent power delivery.

As far as fuel delivery is concerned, the R1 squirts petrol into the cylinders via electronic injection, and dual-valve throttle bodies with clever motor-driven secondary valves ensure that opening up the throttle results in immediate response.

Complementing the new R1's highly engineering engine block is yet another all-new aluminium Deltabox frame.

The main frame rails actually pass over the engine instead of around it. This results in a structure that's supposedly 200-percent more rigid vertically, 50-percent stiffer laterally, and 30-percent stiffer torsionally.

With the increase in rigidity, frame width is reduced from 464 to just 395.6mm. This helps create more comfortable ergonomics for the rider, as well as more efficient aerodynamic penetration.

Other changes to frame geometry include 10mm higher clip-on handlebars, footpegs that have been moved 2.5mm forward and 7.5mm lower, plus the fuel tank is now narrower than the 2003 model R1.

Deceleration is taken care by the aforementioned 320mm dual front disc brakes shod with radial-mount calipers, while a single 220mm disc shrouds the rear axle.

A Brembo radial-pump front master cylinder (w/adjustable lever) also helps reduce stopping distances.

Suspension-wise, and the head-turning new 998cc Yamaha gets a tasty set of fully adjustable KYB inverted telescopic front forks, which are said to have stiffer springs than the 2003 YZF-R1. The piggyback rear shock also gets a stiffer spring.

Reducing unsprung weight, the R1's new 5-spoke wheels are a full 10% lighter up front and 7.5% lighter at the rear, and the underseat titanium exhaust system contributes to a reduction in drag, while at the same time allowing for greater angles of lean mid-corner - 56° more cornering clearance, to be precise.

Lastly, a new instrument panel has also been installed to complete the round of new features for the stunning new Yamaha YZF-R1.

It comes with an illuminated and adjustable LCD, plus multifunction digital gauges including an odometer, dual tripmeters, water temperature, air temperature, full-time clock and lap timer.

The centre of the instrument cluster is dominated by a large 15,000rpm analogue tachometer with an adjustable shift light.

When all is said and done, Yamaha looks to have the most advanced, not to mention most powerful, 1000cc motorcycle in 2004. It looks the part too, with a dynamic new fairing and other technical features that blend in nicely.

But don't discount Honda's CBR1000RR or Kawasaki's ZX-10R Ninja either, who are still very much contenders in what is arguably one of the tightest open class fields ever seen.

While the Suzuki GSX-R 1000 is also still in the fight, what with a lighter 168kg kerb weight, but less power (about 160bhp), the Yamaha looks to be the power-packing tool of choice in the litre-class of bikes. After all, more power and less weight = more fun.