Middleweights In Real Life

It's easy to cursorily dismiss these bikes as also-rans in the middleweight sportbike world: Why pick the has-been diva when the nubile starlet is calling your name? But the fact is the ZX-6E and YZF600R can still carry a sporting tune-- although they have a little trouble hitting those high notes--and both can boast certain traits absent in their younger counterparts.

The Yamaha YZF600R made its debut in 1994 (with Jamie James taking it to the 600 Supersport Champion-ship), received new suspension in '96, and had a major makeover in 1997 with new brakes, bodywork, upgraded engine internals along with bigger carbs and ram air. Kawasaki's E-model ZX-6 has been around since 1993 (when it won the AMA 600 Supersport championship with Miguel DuHamel aboard) and has remained unchanged since. The little Kawasaki was quite advanced for its time, sporting an aluminum frame and using ram air with big carburetors to dominate the performance testing of SR's 1993 middleweight comparison test.

Enough history, on to the ride. In the age of fuel injection and automatic choke, it's a nice surprise that both of these bikes start immediately hot or cold, allowing you to ride away as soon as you please. The Kawasaki runs cleanly right from idle, and its light clutch pull (the lever has a 5-position adjuster, a nice touch) makes pulling away a no-brainer. The Yamaha has the tiniest of hesitations off idle, which never seems to completely go away as the motor warms up, and the engine will stutter a moment--and almost stall with a passenger aboard-- unless a good deal of clutch slip is used.

Both the YZF and the ZX-E weigh in at just over 490 lbs. with full tanks of fuel, but couldn't carry their weight more differently around town. The Kawasaki's seat is quite low, the bars narrow and the pegs forward. While steering is light, the narrow bars make the ZX feel a bit bulbous at low speeds, and the forward and high-set footpegs give you no leverage to help steer the bike either. Bottom-end power is ample, and the Kawi's short gearing and rev-happy engine make outrunning even the most aggressive SUVs no problem. The mirrors--a bit stiff to adjust--are wide-spaced and provide an excellent view. It's the bike's amenities (clock, fuel gauge, good bungee hooks, neutral finder) that make the daily commute easier yet. Passenger accommodations are excellent with a spacious, flat seat and large grab handle.

Yamaha added ram air to the YZF600 for 1997, along with the swoopy bodywork. The monoblock brake calipers are excellent when up to temperature, but need a heavy hand in the city when cold.

The YZF600R's steel frame is plenty strong for the job, but contributes to the bike's height and mass compared to newer sportbikes.

Yamaha's YZF600R has clip-ons that are wide and splayed, making the reach a bit long for smaller riders. The large gauges are easy to read, although the master cylinder reservoir hides the temperature gauge somewhat.

The Yamaha has more of a VFR800-ish seating position, sporty but somewhat relaxed from even the R6, and hides its weight well in the city. The YZF does feel a bit larger than the current middle-weights--almost 750-sized--but seems to shed a few dozen pounds above walking speed all the same. The Yamaha lacks the amenities of the Kawasaki, with no clock or fuel gauge, but its analog gauges are large and easily read. The mirrors provide a good view if you move your elbows in just a tad. Low-end power is surprisingly stout, and little transmission work is required in town. Coming to a stop from slow speeds can be a bit dodgy at times though, as the Yamaha's front brake pads need some heat in them in order to work to their full potential--and you won't generate that heat puttering around town. A good pull on the lever is all that's needed to get decent stopping power, but that first stop of the day catches you out. The ZX-6's binders, with a sharp initial bite and good consistent power, are somewhat nicer in the city, although their long lever travel (both front and back) takes a bit of getting used to.

The ZX-6E was one of the first middleweights with ram air induction, and its twin scoops are large even by today's standards. The Kawasaki's brakes are fine around town, although they lack the progressive feel of more modern binders when pressed hard.

The Kawasaki's beam frame is aluminum, and feels quite sturdy. Even with a centerstand and twin exhausts, the ZX-6 weighs in just five pounds more than the YZF.

The ZX-6E's clip-ons are high, narrow and quite angled for a comfortable position. The forward mirrors provide an excellent rearward view, but are difficult to adjust. Analog gauges are excellent, and include a fuel gauge and LED clock.

Getting up to cruising speeds, both bikes are, as you'd expect, considerably more comfortable than most of the current roadburners. The Kawasaki's upright riding position is great for short-to-medium hauls, say a couple of hours, until you find that the high pegs and scalloped seat limit you to a single position. Wind protection is quite good, and there is only a slight vibration in the footpegs--none in the handlebars, even at triple-digit speeds. It's the ZX-6's suspension that can cause the most trouble on the freeway, though. Smooth roads are fine, as the Kawi's boingers are soft and quite plush. Expansion joints, however, will have your kidneys feeling like they're being tenderized as the damping-rod fork simply locks up over the sharp-edged bumps. No, there's not a lot of adjustment either--preload both ends, rebound damping up front, and rebound (also affecting compression) out back. Bring on the cartridge emulators, please.

Suspension Settings: Kawasaki ZX-6E

FRONT: Spring preload: 2 lines showing; Rebound damping: full stiff. REAR: Spring preload: 4 turns stiffer than stock; Rebound damping: full soft

Having undergone a suspension upgrade in its 1997 Thunder Cat transformation, the YZF has the advantage of a cartridge fork and remote-reservoir shock, and the bike rides smoothly on the highway. The tall windscreen does an excellent job, and there is very little buffeting. The wide, flat seat does allow some room for moving around over the course of a long trip, although its forward slant will force you up against the tank soon enough--ditto for the passenger seat, which is heaps better than say, the R6 even so. There is some vibration in the pegs and clip-ons at various resonances, and if you can find a speed at which they smooth out it is possible to cruise for quite a distance--good thing too, as the Yamaha's five-gallon tank and excellent fuel mileage let it go over 200 miles on a tankfull easily.

Suspension Settings: Yamaha YZF600R

FRONT: Spring preload: 5 lines showing; Rebound damping: 3 clicks out from full stiff; Compression damping: 11 clicks out from full stiff. REAR: Spring preload: position 4; Rebound damping: 8 clicks out from full stiff; Compression damping: position 2

As you would expect, the Kawasaki is a sporting notch behind the more technically current YZF600R, although the gap--and the difference to recent middleweights--is less than you would think. The ZX-6E's steering--even with the narrow bars and little leverage from the forward footpegs--is very light and quick, especially after we correctly set front and rear sag, significantly steepening the geometry in the process. We quickly found the Kawi's tires to be a limiting factor, however. Its Bridgestone BT50s are several generations old, and seemed simply too hard and stiff for serious canyon work. Less of a factor, but still a concern, is the bike's suspension. While its initial compliance is good, the fork is still on the soft side with full rebound dialed in, and the rear shock's damping adjuster is buckboard stiff on even its softest setting. Sharp-edged bumps will have the bike bouncing off-line and running wide, a situation made worse when you realize you can't just bank the bike in a bit more on those tires.

The ZX's engine is quite willing to take whatever you throw at it, enduring extended twisty sections without the tach once reading below 10K rpm--a necessity if you want to make good time. You'll be rowing on the shift lever quite a bit doing that, and the Kawi's tranny, with a long, light throw, plays along nicely. In the upper reaches of the powerband, however, a deft touch is required with the throttle as there is some hesitation on corner exits, almost as though you are pulling against the vacuum of the engine. The brakes, fine in the city, require some finesse also. "Strong initial bite" quickly turns into "grabby" with peg-scraping lean angles, and our test unit's front brakes began squealing and grinding partway through the test.

Test Notes: KAWASAKI ZX-6E

+ User-friendly power
+ All the conveniences
- Archaic suspension
- Outdated rubber
x Excellent introductory sportbike

Still, the Kawasaki's basic chassis feels quite solid, and its long wheelbase gives it some stability in the faster, rough sections that you think would tie the bike in knots. Some simple upgrades--tires and some suspension work--would go a long way in improving its sporting prowess.

Yamaha's YZF, while no R6 in the handling department, acquits itself quite well in the canyons. Its steel-framed chassis is solid, and the tall/thin layout helps hide its extra heft. The front suspension is on the plush side, although the combination of the 60-series front tire and stiff high-speed compression damping in the fork have the front end feeling flighty in rougher turns and chattering when turned in hard on the brakes. Steering is light and neutral at speed, and mid-corner corrections are a light push on the bar away. The brakes--not our favorites in town--become outstanding for power and feel when used in anger, displaying the typical monoblock progressiveness.

Test Notes: YAMAHA YZF600R

+ Strong motor and chassis
+ Awesome brakes
- Suspension could be better
- A bit porky
x Great budget sportbike

The engine's excellent midrange and revvy nature help tremendously in tighter twisty bits, although at higher revs the light throttle can be unexpectedly abrupt--especially after coming off the Kawasaki and its somewhat sticky action. Transmission action is very R6-like, with a short, slightly stiff throw clicking each gear positively. Overall, you won't be that far behind your buddies on their new bikes after a canyon sortie, but you'll definitely have had to work a bit harder at it.

As a first sportbike, the Kawasaki has a lot to offer: a low seat height and unintimidating ergos, light handling, and the potential for easy performance upgrades to match growing skills. The Yamaha is more for the budget-minded sportbiker. Yes, it's a newer design than the ZX-6E, and definitely more sporting. But it also has a harder edge, with ergos and fewer niceties to match. Both make good jack-of-all-trades bikes, providing enough sport for most riders, and quite capable of a weekend getaway complete with luggage and a passenger.Truth be told, we had grins inside our helmets during the whole test, even when bombarded with snide comments from the weekend riding buddies. How does it go? "Old age and treachery..."

ZX-6E vs. ZX-6R and YZF600R vs. R6: The real-life/performance trade-off

While the ZX-6E and YZF600R certainly lag behind their current-day counterparts in all-out performance, the differences are smaller than you'd expect. And, in some respects, the "older" bikes are actually superior to the ZX-6R and R6.One of the more important considerations for purchasing either the E-model Kawasaki or the R-model YZF is price. You'd save 700 bones between the Kawasakis, and there's a one grand difference between the Yamahas. Not a whole bunch at first glance, but consider this: you can expect to pay full pop for the 6R or R6 (if you can even find one...) but your local dealer will be more willing to bargain for the 6E or YZF. Effectively, you'll save more than what the difference in MSRP suggests.

The scalloped seat of the ZX-6E makes the bars seem higher and closer than they actually are. The seat-to-peg distance is similar to the ZX-6R, and a bit tight given the upright riding position.

What about a used F4 or the like for the same price, you say? Certainly that's an option, but there's a lot to be said for a new bike complete with warranty, easier financing, and a helpful dealer as opposed to the unknowns of buying used.

Both the ZX-6E and YZF-R have more comfortable ergos than their newer brethren, although we'd say the YZF is about equal to the ZX-6R in that respect. Passenger accommodations are vastly better on both of the older bikes, however. Comparing details, the two Yamahas are similarly equipped--that is to say, there's not much extra on either bike aside from the clock on the R6 (none on the YZF). Between the Kawasakis, the ZX-6E has some features lacking in even the 6R, such as the centerstand and fuel gauge. Both bikes have LED clocks.

Slightly more relaxed than the R6 in every ergonomic measurement, the YZF600R is comfortable enough for an all-day ride, yet the seating position is aggressive enough in the twisties.

Think the latest and greatest bikes have way more power? In one way, you're right. The R6 has about 9 peak ponies on the YZF, and there's more than a 10 horsepower difference between the two Kawasakis, but check out those dyno charts. In the lower rev range, the two ZXs make virtually identical power, and the YZF has even more midrange than the R6. Isn't technology great?

One of the biggest differences between the sportbikes of today and yesterday is their weight: More than 60 pounds separate the old from the new in this case, and it's quite noticeable, offsetting even the YZF's midrange horsepower advantage over the R6. It's the mass of the ZX-E and YZF--along with their suspension, to a lesser extent--that most affects their sporting prowess. If performance is what you crave, the newer bikes are a definite step ahead of the 6E and YZF. But it's only on the outer edges, where 10 percent of us ride 10 percent of the time, that the extra performance is useable.

The E- and R-model ZX horsepower curves criss-cross each other up to almost 10,000 rpm, pretty impressive considering the E is 10 years old and the R has one of the more potent midranges of all the current middleweights.

Wow! The YZF600 stomps all over the R6 right up until 10K rpm, pulling as much as 12 horsepower more than the R6 in the midrange. The difference is somewhat offset by the R's weight, but still noticeable.

Things that make you go hmmm: Our original ZX-6E (in SR's 1993 middleweight comparison) churned out over 93 horsepower. In 2002, less than 85 HP.

Sport Rider Opinions

ANDREW TREVITT
Totally bummed that Steve Mikolas wasn't around for this test so that he could be roasted like last time.

Everyone looked at me strangely when I showed up for our Sunday ride on the YZF600R--well OK, I get strange looks all the time--but just this once it was because of the bike. Why take the YZF when there are all those cool bikes waiting in the shop? Because I had all the fun of the newer bikes, didn't fall behind any further than usual, and at the end of the day I could have gone another tankfull, easy. Same deal with the Kawasaki, although it's a bit of a chore to keep the others in sight with that bike.It's tough to keep the ZX-6E out of the YZF's shadow, but for a newbie sport rider the Kawasaki's got a lot to offer, and I've been recommending it to people as a first sportbike. It's just some tires and suspension work away from serious sportiness too, easy upgrades that don't cost a whole bunch. As an experienced rider, I could see buying the YZF over the R6--the money saved would be worth the sacrifice in performance. But I'd have to find an awfully good deal on a ZX-6E before I'd choose it over the ZX-6R--which is almost as comfortable to boot.-A.T.

KENT KUNITSUGU
Angry that this test took him away from riding his precious GSX-R1000. Also bummed about Mikolas.

I can remember when these two were the cream of the crop for 600cc sportbikes. The Kawasaki ZX-6E was the horsepower king of the class; a little heavy, perhaps, but the engine and chassis pretty much made up for it. And I'll always remember Jamie James pulling seemingly impossible braking passes into turn one at Daytona on his Yamaha YZF600R supersport bike back in '94.Nowadays, everyone is caught up in the razzle-dazzle 100-plus horsepower/near-400-pound wet weight/55-inch-wheelbase hysteria of the middleweight class. Neither the ZX-6E or the YZF600R would garner even a cursory glance in the headlong rush for the ZX-6Rs and R6s. But many riders out there would go far better on the former machines, especially the Yamaha. The YZF doesn't require you to tap dance on the shift lever or maintain 100 percent concentration during aggressive cornering to generate speed. And its chassis is far more forgiving as the speed rises than the experts-only R6.Do an honest assessment of your riding skills. If you've been riding for a year or less (or if you're a beginner, but you've got your heart set on a new 600cc sportbike), I can almost guarantee that you will learn more about riding fast in less time on the YZF600R than on the R6.-K.K.

Specifications

Performance Numbers