Yamaha has finally released full specifications for its new middleweight street sportsbikes, the naked FZ8-N and semi-faired Fazer8. A 779cc engine derived from the FZ1 donk is the star of the show, with a complete FZ1 frame and swingarm as well. The new engine makes significantly more torque than the smaller FZ6 for a gruntier, more accessible power curve around town - but builds to a healthy 105-horsepower top end rush when it's time to get a boogie on. It looks like a fun, fast and friendly street sportsbike - and yes, FZ6 fans, it has formally replaced the 600 in the FZ lineup.

As many have suspected, the engine is indeed a scaled-down version of the fuel-injected 1000cc FZ1 engine, dropped to 779cc by reducing the piston bore, increasing compression, swapping out the pistons, crankshaft and top end. The resulting motor puts out a touch under 105 horsepower, with 82 Nm of torque.

Effectively, that top-end horsepower figure doesn't seem to be much up on the 90-odd rear wheel horses offered by the lighter, 600cc FZ6 donk. But the stroked-out FZ8 makes its power much earlier in the rev range, a fact which should make it a much more willing and eager powerplant around town and in the majority of real-world riding conditions.

The bad news is that by reducing the FZ1 engine's bore, the FZ8 doesn't manage to shed any engine size or weight. The good news that comes as a corollary is that the FZ8 is blessed with the wonderful FZ1 frame and swingarm, which do an excellent job of providing rigidity and flex in all the right places.

There's not a lot for gearheads to get excited about elsewhere; suspension seems fairly basic, adjustable only for rear preload, and the brakes are four-piston monoblock jobs, with the option of adding ABS.

There's two versions available, just like with the FZ6 and FZ1 platforms - the naked FZ8-N looks nice and chunky and stylish, and the semifaired Fazer8 looks a little more... Practical. The FZ8-N weighs 211kg ready to roll with a full tank of gas, the Fazer8 215kg - and you can add 5kg to either if you want the optional ABS.

Where does the new Fazer fit?

The FZ8 has clearly been developed to help Yamaha get a foothold in the 750cc class, which is currently occupied only by Kawasaki's Z750 (itself a sleeved-down Z1000) and Aprilia's Shiver. Other key contenders would have to include Ducati's 696 Monster and the excellent Triumph Street Triple 675. You have to wonder why Suzuki doesn't make a sporty naked using its excellent GSX-R750 donk - the only purebred 750cc sportsbike engine on the market - but then, they don't use the Gixxer 1000 engine in a naked, either.

Looking at the engine and weight specs, you'd have to rate it next to Honda's everyman CB900 Hornet as well - I've got a soft spot for those, as I put 60,000km on one a few years back.

100-odd horses and 82Nm of torque should stand the FZ8 in good stead as a powerful but friendly and useable roadbike, and it certainly carries forward Yamaha's tradition of making some the best looking of all the Japanese bikes. So in all, it's no major leap forward, but it's certainly a great addition to the FZ range.

Speculation has been mounting in certain corners of the Internet that the FZ8 has been designed to effectively replace the FZ6. Such scuttlebutt postulates that the 'friendly' 600cc category will be handled by the more utilitarian XJ6 and Diversion, and that the highly-strung FZ6, which needs a lot of revs to feel like it's taking off, will disappear so that Yamaha can position the FZ range as a naked sports option for more experienced riders. And if Yamaha Europe's website is anything to go by, it seems the rumours are true - the FZ6 and Fazer6 have disappeared altogether.

The FZ6 certainly has its fans, plenty of people like the retuned R6 engine's marked power curve - but if the FZ8 manages to pull off that same top-end rush, while adding in some genuine usable torque down low, I think it's fair to say you've got an all-round more useable bike. We look forward to riding one! Full specs follow, and there's loads of photos in the FZ8 photo gallery.

2011 FZ8-N and Fazer8 Technical Specifications

Type : Liquid cooled 4-stroke,DOHC, Forward-inclined parallel 4-cylinder
Displacement: 779cc
Bore x stroke: 68.0×53.6mm
Compression ratio: 12.0: 1
Max. Power: 78.1KW(106.2PS)/10000r/min
Max. Torque: 82.0Nm(8.4kgf・m)/8000r/min
Lubrication system: Wet sump
Fuel supply system: Fuel Injection
Clutch type: Wet,multiple-disc coil spring
Ignition system: Transistorized coil ignition
Starter system: Electric
Transmission system: Constant mesh 6-speed
Final transmission system: Chain
Primary reduction ratio: 1.512(65/43)
Secondary reduction ratio: 2.875(46/16)
Gear ratio 1st gear: 2.692(35/13)
Gear ratio 2nd gear: 2.063(33/16)
Gear ratio 3rd gear: 1.762(37/21)
Gear ratio 4th gear: 1.522(35/23)
Gear ratio 5th gear: 1.350(27/20)
Gear ratio 6th gear: 1.208(29/24)

Frame: Deltabox frame
Front suspension: Telescopic fork
Front wheel travel: 130mm
Rear suspension: Swingarm (link suspension)
Rear wheel travel: 130 mm
Caster angle: 25º
Trail: 109mm
Front brake: Hydraulic dual disc brake, Ø 310 mm
Rear brake: Hydraulic single disc brake, Ø 267 mm
Front tyre: 120/70 ZR17 M/C(58W)
Rear tyre: 180/55 ZR17 M/C(73W)

Overall length: 2,140mm
Overall width: 770mm
Overall height: FZ8-N 1,065mm / Fazer8 1,225mm
Seat height: 815mm
Wheelbase: 1,460mm
Min. ground clearance: 140mm
Wet weight (full fuel tank): FZ8-N: 211kg / ABS 216kg - Fazer8: 215kg / ABS 220kg
Fuel capacity: 17 litres
Oil capacity: 3.8 litres

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