• 600cc supersport bikes were once developed on par with their bigger counterparts.

• It was the most popular class and outsold the bigger bikes.

• The class has been in decline but why?

We looked at the genesis of the 600cc supersport models in Part 1, so let’s take a look at more of the groundbreaking models in this part.

As we mentioned earlier, the class became a hotbed for sales across the world as riders sought bikes that are not only cost less to buy, they cost less to insure, too. Besides that, 600cc bikes were getting pretty fast but were still relatively easier to ride than their 750cc and 1100cc counterparts. The category should have seen ongoing developing and good sales, but something happened along the way to cause its decline.

Kawasaki Ninja ZX-6R (1995)

Sure, the ZZ-R600 was fast and handled reasonably well, but there’ no getting away from its sport-touring platform. No one is going to race that and win.

So, Kawasaki chucked out that format and returned to with a sporty 600 in 1995. With a bodywork based on the Ninja ZX-9R, the ZX-6R had ram air intake too, which upped engine power to 101 hp. That made it the first production 600 to go above the “ton.” It went faster too, hitting 262 km/h.

Now the power wars were on.

Suzuki GSX-R600 SRAD (1997)

Suzuki finally got on the ball and released the GSX-R600 a year after the groundbreaking GSX-R750T. The smaller Gixxer was based almost thoroughly on the 750, albeit with a sleeved-down engine, adjustable but conventional telescopic shocks and 4-piston front brake calipers. But it did have Suzuki Ram Air Direct (SRAD).

It was a manic bike on the road, suited to twisty roads that’ll have bigger bike riders holding back on the throttle.

Yamaha YZF-R6 (1999)

The class is going to get even hotter. Yamaha finally fought back with the sublime YZF-R6, a year after launching the YZF-R1. However, the R6 didn’t share any parts with the R1 except for a compact, light and agile concept.

As per the R1, the R6 received a “stacked” transmission. It shortened the engine and provided the bike with a short wheelbase (shorter than the FZR400RR). That allowed engineers to move the fuel tank backwards and consequently the handlebars toward the rider. It was the beginning of mass centralisation.

The manic inline-Four spun to 13,000 RPM and put out 120 hp. Since it was also light, it accelerated faster and had a 265 km/h top speed.

Triumph TT600 (2000)

Triumph decided to get into the middleweight market too, since it was thriving. It was a brave decision since the new Triumph had to contend with what the Japanese had done for many decades.

So, the Hinckley manufacturer gave the TT600 the best components such as an aluminium frame, fuel-injection, forged pistons, fully-adjustable suspension and top-of-the-line Nissin brakes.

It handled really well, as a result but the engine was blighted by spotty fuel injection programming.

Kawasaki Ninja ZX-6R/ZX-636 (2003)

With the everyone in the class now fighting tooth and nail, Kawasaki decided to up the power of their ZX-6R. Not in the conventional term, instead by upping engine capacity to 636cc. This “cheater” engine was for the road, while the manufacturer offered a 600cc machine for racing (like how what Ducati is doing currently with the Panigale V4).

It may have been a 636, but it was as close to an engine tuning gone mad. This is why the engine is a favourite among stunt riders (including one Aaron Twight).

Triumph Daytona 675 (2005)

Triumph wasn’t going to give up and 2005 saw the much-loved Daytona 675. Again, they held nothing back in terms of chassis components but the engine also saw it being changed to a triple. The three-cylinder engine has natural primary and secondary balance, besides having the right amount of torque and top-end horsepower. The 675cc is based on the extra capacity allowance for three-cylinder bikes in racing.

Years of development saw the engine grow to the current 765cc, which also powers the Moto2 grid.

The bike and its later variants were the best-handling 600 supersport. Period.

It had to end…

Suddenly, the 600s were gone. Much of it was due to riders moving on to sport-touring and dual-sport motorcycles. Sportbikes, whether 600cc, 750cc or 1000cc were suddenly spurned as riders seek something more practical to fit a whole variety of uses and roads.

Currently, there are only the Kawasaki Ninja ZX-6R, Suzuki GSX-R600 and Yamaha YZF-R6 soldering on as pure 600cc supersport bikes. However, only Kawasaki and Yamaha are really pushing the development on their bikes. Hang on, though, Aprilia is about to launch their RS660.

There are bikes in the 600cc class at the moment, such as the Honda CBR650R, Kawasaki Ninja 650 but these aren’t true supersport bikes. Still, they’re much more practical at the price of all-out performance.

Will the 600cc supersport class ever see a resurgence? We do hope so.

• 600cc supersport bikes were once developed on par with their bigger counterparts.

• It was the most popular class and outsold the bigger bikes.

• The class has been in decline but why?

600cc supersport bikes were once developed on par with their bigger counterparts and actually ruled the sales sheets in some countries. While there are still three major manufacturers producing them, they seemed to have “disappeared.”

What happened?

Let’s take a look at some of the best 600cc supersport bikes.

Yamaha XJ600 (1984) – The beginning

The Japanese manufacturers were already making sub-600cc machines by this time. Honda had the CBX550 F2, Kawasaki with the GPz550 and Suzuki with their GSX550ES. These were all inline-Fours, with monoshock rear suspension, adjustable forks and disc brakes to boot. Yamaha’s XJ550 lagged behind with twin rear shocks, basic forks and no bodywork.

Then in 1984, they unleased the XJ600, complete with a racy bodywork (which looks much like an RD/RZ), monoshock suspension, all-around disc brakes. The 598cc engine trumped the rest.

Kawasaki GPz600R (1985) – Beginning of the supersport

You guessed right if you thought the other manufacturers would fight back. Kawasaki was the first who did so. What they did was to introduce a new form of 600 – what would become the basis of the supersport class – in 1985. It wasn’t just any 600 wrapped in full-fairing for this was a giant-killer. Legend has it that it would run rings around bigger bikes such as the Honda CB900F, Suzuki GSX1100 and Kawasaki’s own GPz1100.

The engine’s technology was adapted from the GPz900R Ninja (which was the world’s fastest production bike at that point), including the piston stroke. It also had a twin cam, 16-valve head. Liquid-cooling was also adopted from the GPz900R.

Kawasaki didn’t stop there. The bike was given a perimeter frame, adjustable Uni-Trak rear suspension, anti-dive forks, and 270mm diameter brake discs up front. The steering geometry also mimics that of the 900. Finally, it featured radial tyres, which was a new development at the time.

It was the first 600 to be built like a race replica.

Honda CBR600F (1987) – The all-rounder

Honda could’ve fought back with a mad 600, but Big Red has always emphasized rider control which leads to fuller enjoyment. Hence the CBR600F in 1987. It did look racy with the all-enclosing bodywork but as we said earlier, it was made to be ridden everyday, in the canyons on weekends and could still turn in decent lap times at the track. It also had 17-inch front and rear wheels that made for better handling. But most of all, it was made simple and reliable. The CBR600’s legacy lasted for almost 20 years and the engine went to power the Moto2 grid for the first few years.

Yamaha FZR600 (1989) – More sport focus

As competition heated up on the tracks, the 600 class started to take on more sporty vocation like their 750cc siblings. The best example of this was the FZR600. It gained the aluminium twin spar Deltabox frame and bodywork of the FZR750.

The engine however, was a four valve per cylinder job, unlike the FZR750’s Genesis 5-valve head, but the former was given a longer stroke for low down and midrange torque. It resulted in a lively ride, which then became a favourite among the wheelie-happy crowd. It’s said that many FZR600s had oil starvation issues, due to long wheelies.

Kawasaki ZZ-R600 (1990) – First 260 km/h 600

You can bet that Kawasaki always fights back with mo’ po-wa (more power). And they didn’t disappoint with the ZZ-R600. Just like its forebear, the GPz600, Mean Green had upped the GPz900R Ninja to the ZZ-R1100 and scored another world’s fastest production bike title. So, the 600 was again given some of the same tech as the bigger bike.

Along with new-found ram air induction, the ZZ-R600’s engine pushed it to a 260 km/h top speed from a standing start. Not only that, it was faster than most 750cc bikes of the time, and that top speed was just less than 20 km/h lower than the ZZ-R1100’s.

However, Kawasaki somehow made the ZZ-R lineup to more of sport-tourers. But that’s about to change.