Motorcycle Road Test: 2003 Kawasaki Vulcan 1600 Classic

WEB EXCLUSIVE - Updated We received our Kawasaki Vulcan 1600 test bike in April, and rather than make readers wait until July to read about it in the magazine, we have posted the test here.

We now have a couple thousand miles on our test unit, and will occasionally post updates as we have information to add.

We will cut right to the chase. As regular readers know, Motorcycle Cruiser magazine's staff testers have been fans of the Vulcan 1500 Classic in its various iterations since the bike was introduced in 1996. It has consistently ranked at or near the top in our big-twin comparisons for its comfort, impressive all-around function, good looks, solid support from the aftermarket, and great value. Our affection for the 1500 Classic notwithstanding, we think the Vulcan 1600 is a better motorcycle. How much better? We'd say that it's enough of a step up that Vulcan 1500 owners who are ready for a new ride should look here first, and that any big-twin buyer should give it a long look if the style attracts them. However, if you have a Vulcan 1500 Classic FI (see test in the Road Tests section of MotorcycleCruiser.com), we don't think you should feel that your bike has been left behind or rush to buy a 1600, expecting a major change. Though the bike is substantially different, the improvement, both in detail and total effect, is incremental. If you have a four-speed 1500 and like it but have the money and the inclination to move up to a new bike, this motorcycle and the financial incentives created by the current economic climate make strong arguments that it's a good time to jump.

Don't let our statement that the 1600 Classic is an incremental improvement over the fuel-injected 1500 Classic suggest that little has changed. That's not the case. Although the basic crankcase is the same, the engineers and stylists have had their ways with almost everything else. Let's start with the basics. The price is $10,499, or $100 less than the 2002 Classic FI. The Vulcan 1600 Classic is physically bigger than the Vulcan 1500 Classic FI that it replaces. It's longer and fatter, but lower in the saddle. The 66.7-inch wheelbase dimension puts 1.1 inches more distance between the axles than on the 1500 FI. And when you sink into the 26.8-inch-low saddle (a drop of 0.8 inches), you are greeted by a fuel tank that is clearly much wider, thanks in part to an extra quart of capacity. At a claimed 674 pounds (and 746 on our scales, brimming with fuel), Kawasaki says the 1600 is 15 pounds heavier than the 1500 FI.

Turn Up the Volume
And, of course the engine has more internal volume. Although the relatively small Harley 1450cc Twin Cam and Victory 1520cc Freedom engines prove that bigger doesn't necessarily mean better or more power, cruiser buyers apparently like to pack a little extra between their legs. This has led to something of an engine-displacement race, currently being won by Honda's 1795cc VTX. The 1500 Kawasakis, which actually displace 1470cc, were being to look slightly puny. Increasing piston stroke 5mm to 95mm added 82cc, and--at least as important--raised displacement to 1552cc, where it could be rounded off to 1600.

Of course there is more to it than that. By shortening the connecting rods 2.5mm, the engineers kept the engine from getting taller and thereby making the bike more ponderous. New pistons and cylinders are part of the package, with new dished piston-crown shapes that retain the 9.0:1 compression ratio. Longer (by 1.2mm) cylinder sleeves were designed to provide better support for the piston and to counter the tendency for greater ring wear created by the longer piston stroke. This also reduces mechanical noise. The 1600 mill requires 90-octane fuel, despite the digital ignition and detonation-impeding dual plugs in each cylinder. Cam timing has been juggled, with the usual target for cruiser engines: strong low-end and mid-range power. Kawasaki claims 10 percent more torque and 5 percent more horsepower.

More power means more engine heat. The new, narrower (by 10mm), taller (by 20mm) radiator with a more efficient and quieter ring-type fan is touted as improving cooling. We haven't hear it come on during testing despite some hot weather. There is also a dash light to warn of overheating.

Other features of the engine follow tradition for the big Vulcans. Each cylinder has four valves with two springs apiece and a single overhead cam. Hydraulic adjusters set valve-train lash automatically. The single-pin crankshaft and the 50-degree V angle could make for some pretty harsh vibration, but Kawasaki's dual gear-driven counter-rotating balancers stop vibration completely. The induction system retains the dual-airbox configuration, with one air filter on each side of the engine. The fuel-injection system has been remapped and now gets gas from a reconfigured pump (inside the gas tank). The pump's more vertical orientation prevents starvation under braking or acceleration. Kawasaki pioneered air-injection to reduce exhaust emissions, and this bike uses the engine control unit (ECU) to precisely control the air-control valve for greater effect and less mung departing the exhaust.

Powerful Look
The engine has been restyled a bit too. New airbox covers are the most obvious change, but the chrome covers on the cam boxes also have new shapes. The main crankcase is painted a metallic silver, and the oil lines for the top end have been tucked away. The outer cases have been reshaped slightly. Unfortunately, a sight glass on the right side is still used to check oil level, and the bike still has to be standing straight up when you use it. Kneeling down to eyeball the glass while balancing your bike upright is a recipe for disaster. Harley seems to be the only cruiser maker that understands that if your bike only has a sidestand, then your systems (such as oil-level check, fuel filler position, and the sidestand itself) should be designed to be used with the bike resting on it.

Several folks commented on a couple of styling lapses on the engine however. The horn seems to have been simply bolted on using the first bolt that the designer saw. It would have seemed to make more sense to give a pretty chrome cover and then mount it in front of the somewhat ugly engine mount point just above it. The other unwarranted eyesore is a slotted metal tab that sticks up behind the cylinders on the left side of the crankcase. This apparently acts as a retaining tab for a galley plug. A representative of Kawasaki's American distributor couldn't explain why the slotted tab needed to stick up so conspicuously however. He speculated that it might be used for something on a different model or in a different market. (Hearing this, one staff wise guy said, "Oh, you mean it's for a Suzuki?") It appears that it would be a simple matter for an owner to remove the tab and cut or grind off the vertical projection and perhaps have the finished pieced plated,

Of course, the biggest visual change for the power train is the new exhaust system. The expansion chamber that used to tuck under the swingarm on the 1500s is gone (and that space is now empty). It's still a dual exhaust, but now the mufflers conclude with a slash-cut design and appear to have a balance tube. Inside the mufflers are catalyzers, designed to reduce emissions even more. For some riders, the best part will be that the new exhaust has a stronger, more vigorous note. "That's pretty loud for a factory pipe," observed one tester.

The 1600 engine makes an impact with more than just sound though. Motorcycle Cruiser's carefully calibrated editorial hineys indicate that Kawasaki's claims for a five percent horsepower boost and a ten percent torque increase are pretty close. The engine has a minor but noticeable edge in power over the 1500. That's not to say that it has become a powerhouse; the 1500 was at the low end of the big-twin power scale and the additional 82cc has not brought enough of a boost to change that. Power is perfectly adequate, however, and the engine delivers it even more smoothly and pleasantly than the 1500. Our only complaint, and a minor one at that, concerns the slightly abrupt response when you quickly roll the throttle on from trailing throttle. Some of this may simply be excess play in the drive train.

One of the nicest differences in the 1600 engine compared to the various Kawasaki 1470cc engines is a reduction in mechanical noises. There are fewer rattles and metallic sounds.

Like other fuel-injected bikes, the Vulcan 1600 Classic starts readily under any condition. Though there is a "choke" (actually fast-idle) knob on the left front downtube, we never used it, since the engine was happy to idle immediately without it.