Cranking out 158 horsepower at 12,500 rpm, the 2004-'06 model is still the strongest R1, and the last to breathe through 20 valves. OK, so the 16-valve '07 model pulls harder above 7000 rpm. The Genesis version that appeared in '04 is more amenable to travel below 12,000 rpm. The fourth generation of Yamaha's landmark 998cc inline-four was new from the contact patches up. A strategically stiffened Deltabox frame with less trail means more athletic steering. Leaning 10 degrees farther forward than before, the slant-block four was bigger news: bigger 45mm throttle bodies, force-fed for the first time in R1 history by ram air. Intake and exhaust ports got bigger. Bigger, shorter valves top more oversquare cylinders with more compression. Below, a shorter, lighter crankshaft wears shorter, thicker rods.
A full 21 bhp stronger than an '03, at 449 lbs. (wet) the '04 is also 8 lbs. heavier. Still, out on the road, the new bike is superior in every sense of the word. It's a bit soft in the midrange, but acceleration gets serious at 6000 rpm and seriously bloodcurdling above 9000. An even 60 mph arrives in 3.1 seconds from a green light. Low gear is good for 99 mph and sixth takes you to 184. Steering is lighter and more accurate than in '03. Brakes are the class of '04 and so is the gearbox. A narrow fuel tank and humane ergos house tall riders better than anything else in literbike land. Shortfalls? The fork and shock springs are a bit soft for aggro track work and the cockpit impersonates a convection oven on hot days. And the speed-sensitive steering damper can't quell headshake as well as a solid aftermarket alternative. Otherwise, you're looking at first-rate value for money here.
All the usual caveats about complete service records apply. Extra clatter from an '04 top end may mean the cam-chain tensioner is on the outs. Make sure the '05 throttle-position-sensor recall has been handled. And the longer '06 swingarm accommodates oversize racetrack rubber more readily. Frame tweaks, more power and a stiffer triple clamp make the '06 our pick if you can swing the extra cash. But as long as you're not afraid of a few revs, any well-kept example will make you think twice or three times about anteing up for an '07.
A telepathic front end in a 158-horse package sexy enough to make the Italians turn red.
A bit limp in the midrange, engine heat makes hot days hotter and you'll need stiffer springs for track days.
Vulnerable cam-chain tensioner in '04 and TPS recall in '05. Low coolant level can give the black box a headache.
A comfortable, capable liter-class contender for those who aren't afraid of revs.