Santa Barbara, California, February 28, 2000 -- Back in the seventies, motorcycles were evolving at an unprecedented rate. Motors got faster and suspension technology was making leaps ahead every year. Street bikes got bigger motors that overpowered the chassis they called home and brakes were horribly inefficient. Even on motocross bikes, twin shocks were replaced by mono-shocks that soon started working through linkages to get different ratios and increase wheel travel.
Soon, suspension travel exceeded 12 and even 13 inches, until people started to realize that maybe there is too much of a good thing, after all.Could this be deja' vu all over again with Honda's latest big-bore cruiser, the VTX 1800? In a word: No! Bigger, in this case at least, is better.
In an attempt to capitalize on the fastest-growing segment of our sport, cruisers have become a primary focus for many manufacturers, both Japanese and, of course, American. And while some choose styling over substance (read: performance) Honda has done their best to give us what they feel is a bike complete with "forward-looking" style and a motor that's unlike anything ever fitted to a cruiser before. Even the exhaust valves are larger than on a P-51 mustang!
We recently trekked to the coastal town of Santa Barbara for the press introduction of Honda's latest and greatest. In between spouts of rain, we were able to spend some saddle time on what Honda feels will be the bike that has the chests of Red Riders everywhere swelling with pride, and the bike that steals quite a few sales away from those "other" cruisers that, some say, are still stuck in the past.
Tech Briefing
Traditionally, Honda's cruiser line-up has been varied, yet comfortable and reassuring -- nothing fancy and certainly not anything risky. So what happens when Honda engineers are given a clean sheet of paper to scribble and doodle on? You get the VTX, that's what. Equipped with a rubber-mounted, 1,795 cubic centimeter, 52-degree, fuel-injected V-twin engine, the VTX is unlike any other cruiser in the Honda line-up.
"The engine features the largest connecting rods and cylinders (a whopping 4-inch diameter, in fact, just like a 400 Chevy!) ever made in a Honda facility."
The concept of the VTX started as early as 1995, although the actual design process began in 1996. Honda designers were given a clean sheet of paper to design the nastiest and gnarliest machine around. Of course, a product of that nature doesn't just pop into a person's mind. Usually, inspiration is required and in this case, it came in the form of a 1995 concept bike, the Zodia, that made its rounds throughout the world as a well-received motorcycle show spectacle. Long and low with inverted forks, dual-chromed shocks and sleek chrome-hooded headlight, the VTX designers make no bones about what bike they drew inspiration from.
The engine features the largest connecting rods and cylinders (a whopping 4-inch diameter, in fact, just like a 400 Chevy!) ever made in a Honda facility, and this includes both cars and bikes. It goes without saying that a twin-cylinder machine with such large displacement would produce a prodigious amount of vibrations. To quell the wild animal within, Hondaneers outfitted the VTX with a 41.4 pound, offset dual-pin crankshaft. A titanic first impression, for sure, but it's still got a narrow girth: By using two bolt-on balance weights, they saved 8.8 pounds and reduced crankcase width by nearly two inches versus producing a one-piece item.
Moving to the cylinder heads, you'll notice the traditional Honda dual-plug, three-valve cylinder head design (two intake, one exhaust). The difference between this and other Hondas, though, is the immense girth of the various parts. For example, two 36mm intake valves feed the 101mm bore (that's 3.97 inches) and 112 mm stroke (4.41 inches) mill. Think thats big? How does a 45mm exhaust valve sound? Just for reference, the diameter of the fork legs on the VTX are also 45mm. But even with such gargantuan valves, Honda still incorporated simple screw-and-locknut valve adjusters to keep maintenance a do-it-yourself affair.
Air makes its way into the cavernous cylinders by way of dual 42mm throttle bodies. Fuel, pressurized to 50 psi, is injected via dual injectors featuring 12 orifices for more efficient atomization -- a first on a production vehicle. All of this is controlled by 3-D fuel-injection and ignition maps for each cylinder. Due to Honda's diligence and the use of a closed-loop emission control system, the California version of the VTX meets all CARB Tier 2 (2008) standards, losing only one horsepower in the process. Also, the 49-state version exceeds the CARB Tier 1 (2004) level.
After ignition, exhaust gasses are swept out by a two-into-one exhaust that has to be the most obscene phallic symbol ever fitted to a production motorcycle. In other words, we like it. During the prototype phase, the engine would create such significant "power-pulses" that the exhaust shook a tremendous amount. This vibration was remedied, of course, as were the shakes that crept into the head-lamp and gas tank in pre-production models.
While the exhaust gasses may have a free path to escape, power is harnessed by an eight-plate clutch and five-speed gearbox. A shaft takes power to the rear wheel since the motor simply produces too much torque for any sort of belt-drive system currently available.
In order to slow all 705 pounds (claimed dry weight), the VTX features a unique version of their Linked Braking System. Instead of having all the brakes linked together in typical fashion, the VTX has independent front brake control, with the rear brake activating both front and rear calipers. However, the rear brake will only actuate the center of three pistons on the front caliper in conjunction with both rear brake pistons.
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