Powersports / ATV / Utility / FourTrax Foreman 4x4 ES Power Steering
Without a doubt, all-terrain vehicles have changed the world. And perhaps none has been more influential than the FourTrax® Foreman®. When an ATV serves as a tool that carries you through 10-hour days and 60-hour workweeks, then becomes your weekend recreational vehicle as well, there is no such thing as an irrelevant detail. That's why Honda ATVs have always been about smart solutions to tough problems, and that sort of fresh thinking can be seen throughout the lineage of the Foreman in landmark Honda innovations that have shaped the development of the ATV.
Foreman firsts date back more than a decade, when the 1995 model introduced the world to Honda's innovative longitudinal engine design. In 1998, the Foreman was the first ATV equipped with Honda's Electric Shift Program (ESP™). Four years later in 2002 came TraxLok®, and in 2005 the Foreman became the first ATV to use Honda's patented dual oil-cooler system and collet-style front disc brakes with integral scrapers. And of course, 2007 marks the single biggest leap forward in ATV chassis evolution with the introduction of Electric Power Steering (EPS™).
What follows is a look back at the Foreman innovations that came before EPS.
Perhaps Honda's most ingenious bit of bright-think revolves around the powerful efficiency of its longitudinal engine and driveline layout introduced on the 1995 Foreman 400 and currently found in all of its utility ATVs. This optimal system sends power to the wheels in the most efficient manner: straight lines. The longitudinal layout has many advantages: lower center of gravity, low seat height, increased ground clearance, lighter weight, and fewer moving parts than traditional engine driveline systems.
By aligning its crankshaft with the vehicle's direction of travel, the longitudinal layout creates a lighter, simpler, elegantly efficient way of sending power to an ATV's drive wheels. This simplicity may be best seen in the driveline: Using 45 percent fewer parts, the Foreman 400 4x4 transmission, for example, weighed 41 percent less than the more conventional design used in Honda's legendary FourTrax 300 4x4 while delivering power to the wheels with five percent more efficiency. Honda's longitudinal engine also rides low enough in the frame to optimize ground clearance and define a low seat height, a difficult accomplishment in ATV design.
Electric Shift Program (ESP)
For some riders, operating a conventional manual gearbox can be daunting. To offer an alternative, Honda developed the revolutionary Electric Shift Program (ESP), introduced on the 1998 Foreman. ESP provides push-button upshifting and downshifting. The rider shifts simply and precisely with the press of the upshift or downshift button mounted on the left handlebar. An onboard electronic control module (ECM) monitors information from four sensors-engine rpm, countershaft speed, shift drum angle and shift spindle angle-to control the speed of the electric-shift motor's gear and clutch engagement. Gear-engagement speed varies according to rider style: The transmission shifts more quickly when riding style turns sporty. A Neutral lockout at speeds greater than 2 mph ensures available engine braking when descending hills. For smooth shifting, the transmission cannot be shifted from Neutral to First gear or Reverse at engine speeds above 3000 rpm. ESP is not battery-dependent; it operates whenever the engine is running. Should the rider ever need to shift manually, the ES model is also equipped with an auxiliary shift lever in the toolkit.
To satisfy the need for on-demand four-wheel drive, Honda introduced TraxLok, the company's first switch-operated wheel-drive-changing system, in the 2002 Foreman. TraxLok enables the rider to shift between the nimble handling of a two-wheel-drive (2WD) system and the extra traction ability of a four-wheel-drive (4WD) ATV.
TraxLok is activated by a magnetic switching mechanism-technically known as an electromagnetic mechanical clutch unit (EMCU). This unit actuates a mechanical roller clutch located on the driveshaft near the front differential. This two-way mechanical roller clutch incorporates a series of hardened steel rollers that lock up in a mere 6 degrees of rotation for a smooth, virtually instantaneous response while either accelerating or decelerating, on flat ground or on a hill. And the system operates in Reverse as well.
Moreover, to ensure smooth operation, the TraxLok system is smart enough to engage only when the speed differential between the front and rear wheels is less than 6 mph. In addition, once engaged, the system remains engaged on downhills for true 4WD braking. And when the 4WD mode is engaged, a torque-sensitive, limited-slip front differential reduces steering effort for light steering.
Dual Oil-Cooler System
In creating the trio of 2005 TRX500 ATVs, the development team devised an ingenious feature to enhance long-term reliability. It's one of those "Why didn't I think of this?" kinds of additions that only serves to strengthen Honda's reputation for engineering excellence. Knowing that Foreman ATVs are often subjected to heavy-duty tasks in extreme mud conditions, the engineers developed a dual oil-cooler system, with the second cooler mounted high in the fender area where it won't get clogged with mud over the course of a long, soggy day's work. Naturally, this bright-think idea for extra cooling is patented.
Collet-Style Front Disc Brakes with Integral Scrapers
This innovative dual front disc brake system, introduced on the 2005 Foreman and now used in other Honda ATVs, adds significantly to the TRX500's stopping prowess. These disc brakes feature new collet-style brake calipers that are self-centering for consistent braking actuation. The calipers also have integrated scrapers that eliminate buildup of debris such as mud or ice that might otherwise impede stopping capacity. These scrapers, located adjacent to the disc rotors, clear away debris clinging to the rotors with every revolution of the wheels. It's a small feature that's difficult to detect even under close inspection, but when you're out on the trail or working in the fields, the elegant simplicity of this innovation will leave you grinning ear to ear.