2008 KTM 990 Super Duke Comparison

MotorcycleUSA Staff | September 13, 2010

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Despite being the most-dated machine of the bunch, it’s hard to tell based on the cutting-edge visual appearance of the Super Duke. In this day and age of meteorically-fast new model development cycles, a four-year-old design typically equates for a bike that looks as outdated now as those skull-and-crossbone T-shirts you wore back when you bought it. Unlike your T-Shirts, however, the exterior design of the KTM has somehow managed to transcend time, still looking every bit as modern as its much newer competition.

“The KTM it looks like a bike you’d see in a Terminator movie,” says Editorial Director Ken Hutchison. “Even though the bike is a few years old now it still looks cutting edge. When you pull up at a stoplight people still stare at you and wonder what the heck that is you’re riding.”

Slip into the seat and it is immediately apparent just how comfortable it is. The seat is both wide and thick and proved to be the most comfortable for extended riding. Although the height of the seat is the tallest in this group (33.5 in.) it will only be problematic for vertically-challenged pilots.

The KTM 990 Super Duke rolls on Pirelli Diablo Corsa III tires.
A 999c 75-degree V-Twin engine powers the 990 Super Duke.
Twin undertail mufflers belt out less noise then the Ducatis set-up.
A mixed digital analog display provides information on the 990 Super Duke.
(Above) The KTM 990 Super Duke rolls on Pirelli Diablo Corsa III tires. (Below) A mixed digital/analog display provides information on the 990 Super Duke.

Reach out to the handlebar and your fingers are greeted by an aluminum bar that is well proportioned in terms of both height and bend. It feels similar to the Z1000, however it is slightly wider, which helps give the rider greater leverage when steering. A small orange-backlit instrument display houses an analog-style tachometer with an LCD display that houses information like speed and coolant temperature. The display works adequately but is on the small side, making it harder to read when you’re speed increases.

The position of the foot controls correlate well with the rest of the cockpit and give the KTM the distinction of being the most comfortable bike on which to pile up the odometer numbers. However, its everyday practicality comes at the price of reduced pavement clearance at the racetrack, its footpegs kissing asphalt much sooner than either of the other two machines.

On the road the KTM feels like it carries its weight much lower than the Ducati and in about the same spot as the Kawi. Steer into the corner and it turns in lazily even with the added leverage of the handlebar. While it doesn’t maneuver as fast as the Z1000, it does change direction comparable to the Ducati despite weighing 18 pounds more (445 pounds versus 427 pounds). In transitions the Super Duke gets to full-lean in a predictable manner, though the chassis doesn’t feel nearly as planted nor does it give the kind of feedback at max lean that the race-bred Duc is capable of.

Its WP suspension has versatile damping capabilities and offers a nice balance between real-world life on the road and weekend duties at the track. It delivers a much more forgiving ride as compared to the Duc and similar in feel to the Zed-1. Also noteworthy is how easy it is to adjust the rebound setting on the fork with its clever tool-less adjusters. The OE Pirelli Diablo Corsa III tires complement the chassis well and felt superior in terms of outright grip compared to the Dunlops which come standard on the Z.

In our braking performance test the Super Duke achieved a stopping distance of 131 feet. While it was the longest measured distance, the brakes still worked well, offering an adequate mount of fade-free feedback through steel-braided brake lines. However, its lower-spec braking components just can’t deliver the same stopping power as the Duc’s.

Twist the throttle and you can tell the 75-degree V-Twin, fueling system and throttle are well synchronized, which makes engine power easy to control. Right off idle the engine chugs through its 9800 rpm range with enough snap to raise the front wheel in first or second gear, although it may not happen as psychotically-quick as some of the hooligan-bike crowd may be after; the KTM simply has far less gusto than its faster-revving Italian counterpart.

Mid-range engine performance is on par with the other bikes, the Super Duke pumping out almost 70 lb-ft of torque at a 7400 rpm peak. Top-end engine, however, is noticeably lacking in comparison. The KTM only produces 112 ponies at 9600 rpm – 10 horsepower down on the Kawasaki and a whopping 27 less than the Streetfighter. This means that for optimum acceleration its best to up-shift early and make sure the tach needle is always hovering in the neighborhood of 8-grand.

The 990 Super Duke in action at the racetrack.
The 990 Super Duke is an easy motorcycle to ride at the track.
The KTM 990 Super Duke provides best power at low to mid rpm.
(Abover) At lean the KTM isn’t quite as stable as the racebred Ducati.(Below) The KTM 990 Super Duke provides its best power at low to mid rpm.

The overall character of the engine feels far more refined then the Streetfighter. Where the Ducati is shaking and belting out its obnoxious (to some, melody to others) exhaust note, the KTM generally feels much more refined. Of course, it still gets rowdy as you increase revs, all the bikes in this test do if the right grip is twisted far enough, something which is evident by the results of our sound-decibel test where it registered a 94 dB at 4900 rpm (half of max engine speed). That said it doesn’t come close to the levels produced by the powerplant in the far-more-uncivilized red machine (a good thing to some and not so good to others).

In terms of comfort, there is a mildly-annoying small amount of engine vibration in the lower rev range, though it isn’t nearly as excessive as that produced by the Streetfighter. As rpms climb vibration actually decreases, which makes the Super Duke a worthy ally for the daily commute to work. Additionally, the well-positioned mirrors deliver a clear view of what’s happening behind, not distorting at higher freeway speeds or rattling from vibration when cruising around town.

“The KTM’s engine works well on the street. It’s smooth and manageable and delivers decent get-up-and-go as long as you short-shift it,” noted Hutch. “It sure does sound cool when you rev it out but it doesn’t feel like you’re really going anywhere. The key to riding the KTM on the track is keeping your momentum up and shifting early as well – it’s just plain not a bike that likes to be revved.”

Similar to the Ducati, the Super Duke employs a hydraulically-actuated clutch, six-speed transmission and chain final drive. Not only is the KTM’s clutch easier to use, it also delivers substantially more feel than the vague unit employed by the Streetfighter. The internal drivetrain is complemented by shorter, more street-oriented final-drive gearing, aimed to maximize the engine’s power output under acceleration. Overall the gearbox worked well, with positive engagement between gears and ample feedback from both the hand and foot controls, though ultimately it’s not quite as slick as the Kawi’s set-up.

The 990 Super Duke runs out of ground clearance at extreme lean angles.
The KTM 990 Super Duke runs out of ground clearance at extreme lean angles.

Despite being down on power, in our 0-to-60 mph acceleration test the KTM actually bested the Kawasaki with a time of 3.73 seconds, proving how potent its combination of low-end torque and lighter weight can be as compared to the much porkier Z1000. In terms of quarter-mile numbers, however, the Kawasaki’s enhanced top-end engine performance was simply too robust for the KTM to match, as its quickest pass of 11.28 seconds at a trap speed of 121.42 mph relegated the Austrian machine to the back of the pack.

However, its slightly subdued engine performance pays dividends at the fuel pump. The big Duke provided the longest range of 182 miles based on the capacity of its generous 4.8-gallon fuel tank (biggest in this comparo). We recorded 38 mpg average over the course of our test.

When the score sheets were gathered and the points tallied, KTM’s Super Duke ended up third in this highly-competitive trio. While it scored highly in terms of overall comfort, fuel efficiency and cost, it simply doesn’t serve up the kind of adrenaline-producing performance needed to challenge for a win this time around.

MotorcycleUSA Staff