Power follows displacement...
Power follows displacement in this trio, with the Kawasaki making more power everywhere than the Honda and the Honda similarly out-pulling the Yamaha.
The Powers That Be
So, you had to ride with us all the way to Texas and listen to us dither about this headlight nacelle and that braking system to get to the information you really tuned in for: power. Or maybe you were smart and just skipped to the juicy part. That is what these bikes are about, right? The juice? Well, the cup overfloweth.
Torque is the name of the game with big V-twin cruisers, and the real players are the Honda and Kawasaki. Both are tuned for immediate gratification, and both deliver serious grunt off the line. The Kawasaki's neck-wrenching pull is more visceral from low rpm than the Honda's, confirming the newish adage that "there's no replacement for displacement." It's a brute, plain and simple, and three out of four of us favor it over the Honda mill, which is only a tad less powerful, yet smoother and more gradual, making it feel strong and more usable. The Yamaha truly suffers in this category, and is completely outclassed by the other bikes. At the least it needs the Warrior cam treatment and fuel injection to get it in the beans. For most easy riders, the Yamaha will propel itself around nicely enough, but in the world of the Biggest Big Twins, it's a sad day for the Road Star. (For a more in-depth analysis of these engines, and to see their performance data, including dyno results, see the sidebar, "Thinking Big")
So, by a slight margin, the Kawasaki does get the nod in the category that counts the most for some of you: engine performance. But does the icing really make the cake? We think not. On our last day we rode all the way from El Paso to Los Angeles. Despite the rain, hail and crazy high-desert winds, we had plenty of time to sum it up.
Choosing one of these big twins is very subjective because they each do different things well. In some categories they actually have juxtaposed pros and cons, so it's paramount that a buyer knows what he wants going in. Long trips? Passenger? Sunday cruising? Stoplight showdowns? Canyon rides? Parking-space holder? On the whole, we think all of these cruisers are needlessly heavy and deserve more attention to suspension adequacy and less to keeping seat heights low, which limits ergonomics and ground clearance. All these rigs are well-finished and fun as heck to ride, however, and each is definitely worth its asking price.
So what's the big deal? Three out of four testers chose the Honda VTX 1800N, hands down, as the ultimate Big Twin cruiser, and all three were the core testers who put the majority of mileage on these models. The one rider who didn't choose the Honda said he'd buy the Road Star first for its value, out-of-the-box versatility and comfort. Surprised the V2K didn't come out on top? So were we. The Kawasaki was certainly the favorite to win when this comparison was still an on-paper assignment. And for those of us who didn't favor the newcomer for everyday riding before we left town, there was a certainty afloat that it would find its destiny on the open ride. It didn't take many miles to fall from grace, however, and a coolant leak and potentially problematic exhaust smoke midtrip furthered our dismay. Our advice to the would-be Vulcan purchaser? Wait until next year when the bugs have been sifted through. We are also speculate that there will be an '05 Voyager version truly set up for touring and, Suzuki might offer a V2K with different styling.
Yes, they sure do "grow 'em big in Japan," but we're happy to be the excess-minded Americans who get to enjoy the crop. In gluttony is honor...well, at the very least, a heck of a lot of amusement.
 Aside from size, the VTX 1800's...  Aside from size, the VTX 1800's engine is an almost typical Honda cruiser V-twin. That is, it employs Shadow-like technology in the split crankpins--the connecting rods meet the crank at two slightly skewed positions, not side by side as on the other V-twins here--which helps reduce vibration significantly. (Split pins create other types of vibration in smaller amounts, but aren't nearly as annoying as the large primary imbalance of a narrow-angle--in this case 52-degree--V-twin.) This scheme makes the engine act more like a 90-degree V-twin, which has perfect primary balance. What vibration escapes the split crankpins and the massive, 41-pound flywheel assembly is counteracted by a gear-driven counterbalancer, while driveline shocks are taken up by three sets of dampers, one on the crank end and two in the clutch. Twin-plug combustion chambers are fed by three valves each, two intake and one exhaust, long a Honda hallmark for engines intended to produce little high-rpm power. Unlike the Kawasaki and Yamaha, the Honda uses chain-driven single overhead cams. Generous cooling fins suggest otherwise, but the VTX is in fact liquid-cooled. If you're wondering, the actual redline is 5750 rpm. |  Kawasaki pulled out all the...  Kawasaki pulled out all the stops to make the biggest production V-twin going. With a 103mm bore and 123.2mm stroke, the Vulcan's engine the largest production V-twin and the most undersquare of this bunch, with a bore/stroke ratio of 0.83:1. (Honda's is 0.89:1; the Yamaha is 0.85:1. A typical sportbike's ratio is around 1.5:1.) Generally, a long-stroke engine builds torque strong and fast, as the Vulcan does with a vengeance, peaking at 121.4 foot-pounds, 16.8 foot-pound above the Honda. Its four valves per cylinder--chosen most likely as much to provide additional heat paths through the valves as for their breathing ability--are operated by four pushrods and two cams located in the right engine chest, as Harleys have done forever. Pushrods? On a brand-new design? It makes sense, actually, if you intend to keep the engine as short as possible, a task made tougher by the long stroke. Besides, the rev limit on this engine (actually 5000 rpm) is set by maximum piston speed, which in turn dictates a redline well within the capabilities of a modern pushrod valve train. Hydraulic lash adjusters make the valve train maintenance-free. and Kawasaki's usual excellent gear-driven counterbalancer helps flatten the considerable vibes inherent in this design. |  On a bike intended to house...  On a bike intended to house a classical rendition of the V-twin cruiser motorcycle engine, the Road Star's mildly tuned air-cooled powerplant makes a bit of sense. For 2004, Yamaha increased the bore to match the specification of the Road Star's Warrior stablemate, at 97mm, giving this Road Star engine the same total displacement of 1670cc. Yes, it's the smallest engine here, but that's not why its power lags behind the two bigger bikes we pitted it against. Simply put, the Road Star's 48-degree, air-cooled V-twin engine has very mild camshaft timing, four small valves per cylinder, and must breathe through a single 40mm carburetor. That's partly why the Road Star's engine, at 61.1 horsepower and 93.1 foot-pounds of torque, dramatically lags behind even its Warrior brother, which, thanks to fuel injection, hotter cams and a freer-breathing exhaust system, pounds out 76.3 hp and 97.9 foot-pounds of torque, and has a 1000-rpm-higher redline to boot, even though its basic engine specifications are the same as this Road Star's. Yamaha is keenly aware of the gap, and we are fairly sure the company has something afoot, either hot-rodding or a new injection of good old displacement, to remedy this situation and achieve parity. |