2010–2015 Yamaha YZF-R6

Yamaha's reputation as a builder of quick, nimble, batcrap-crazy middleweights began with the RD350, a "small" bike that kicked the rear fender of some competitors twice its size, especially in race trim as the TZ350. Racing is in Yamaha's blood and is in the YZF-R6's DNA as well. Like its two-stroke ancestor, the R6 has made its mark in the racing world as well as on the street, where it's one of the most wild-eyed, sharp-edged, and narrowly focused offerings in the 600 class.

The R6 asks for, and lavishly rewards, total commitment from its rider. There are 122 hp on tap at the crank—about 103 of them make it to the rear wheel—but you have to spin the tach to 14,500 rpm to get them all. Titanium valves make the trip to the rev limiter go by quickly. Fuel injection fills the cylinders, and a compression ratio of 13.1:1 squeezes it in preparation for ignition. A six-speed transmission chops the engine’s output into usable chunks, and a slipper clutch keeps the rear wheel connected to the pavement during heavy engine braking.

The 41mm inverted fork is adjustable for preload, high- and low-speed compression damping, and for rebound damping. The rear shock offers the same options. It’s all held in place by an aluminum chassis.

The R6's seating position asks the same commitment as the powertrain. Leaning sharply toward the instrument panel rewards you with a close-up view of the analog tach and programmable shift light, both centrally located. Many of the sensations pouring in through the grips, seat, and pegs are a result of feedback gained from running the R6 in World Supersport Championship, which also accounts for its stability and quick steering, two traits not always found together in race machines. A decent if not overpowering midrange accompanies the top-end rush.

The reliability of late-model R6s is enviable, especially for a motorcycle whose engine lives most of its life in five-digit rev territory. Some riders find the downside to a quick-revving engine in its snatchy off-throttle behavior. More have found that it pays to be careful what you wish for; the racy ergonomics don’t give you much time or space to relax between corners. Not great on the highway. Better to find the longer, curvier route to your destination. DIY mechanics complain the fairing is more difficult to remove than it needs to be to perform regular maintenance chores.

The middleweight class progresses rapidly, and a model that lasts substantially unchanged for more than two years is in danger of choking on the competition’s dust by year three. Oddly, that doesn’t really apply to the R6, which has been a competitive track weapon with lots of street cred for a full decade now.

When shopping for a used R6, look for signs of wheelies, burnouts, and the like. Keep in mind, too, that sometimes older bikes become more of a disposable toy than a valued possession. In addition to looking for crash damage and signs of abuse—worn brakes, a dirty and slack chain, suspicious noises from the engine—ask for maintenance records to make sure the seller cared enough about the bike to keep it in top condition.

Focused, uncompromising, a stellar middleweight performer. Not for the uncommitted.

Not too far removed from the racetrack, which can get old on the street.

Engine noises, leaking fork seals, rough idle, clicking valves.

The soul of the RD350 in a modern four-stroke package.

2010 / $6,335
2011 / $6,800
2012 / $7,260
2013 / $7,790
2014 / $8,380
2015 / $8,635

Introduction of the 2006 model was overshadowed by scandal—ads boasted a 17,500-rpm redline, when in fact the ECU shut off the spark at 15,800. Yamaha offered to buy back affected bikes; there were few if any takers. The 2008 model saw engine changes and a horsepower boost, while the 2009 won that year's Daytona 200.

Pretty much a clean-sheet design, with a new chassis, fuel injection, five-spoke wheels, ram-air induction, and updated styling. A claimed 117 hp without ram air, 123 with, and more midrange than before. Despite the lights and turn signals, still more at home on the track than the street, which is what most R6 riders wanted anyway.

A 600cc bike that topped out at 160 mph was amazing in 1998 and still is. The last generation with carbs, horsepower bumped right up against the century mark. The chassis needed some help—"speed wobble" was a term R6 riders learned quickly—but the Yamaha ruled its class until Suzuki debuted a new GSX-R600 in 2001.