A few short years ago, both offroad and on-road motorcyclists looked down on dual-sport bikes. These machines were considered the great compromise of motorcycling: not great performers on the street and lacking punch on the trails. But dual-sport motorcycles have come into their own. Thanks, in part, to the engineers at KTM, the new generation of dual-sport motorcycles are powerful and capable offroad while being legal and comfortable for street riding.
Austrian motorcycle manufacturer KTM is a renowned dirt bike company. KTM's new flagship 500 EXC-F--an example of the finest Austrian engineering--rides at the head of the dual-sport pack. It is a 50-state-legal dual-sport enduro dirtbike powered by a legendary 510 cc SOHC engine atop track-ready suspension.
500 Cubic Centimeters Of Four-Stroke Power
The engine at the heart of KTM's 500 EXC-F gives the dual-sport bike its name. The powerplant is a 510.4cc "racing four-stroke" engine developed in 1989. The engine's type is defined by its single overhead camshaft and 4-valves per cylinder. Its ignition system is a contactless controlled fully electronic ignition featuring a digital adjustment. The engine was originally a longer stroke version of KTM's legendary 450 cc engine. Though KTM's flagship dual-sport motorcycle changed names from the 500 to the 520 to the 525, then the 530 before reverting to the 500, the motorcycle has been the same bike. This machine has received several engineering upgrades since its 1989 introduction.
The 1998 model of KTM's 510.44 cc engine motorcycle boosted the bore/stroke to 95.0x72.0mm with a compression ratio of 11.9:1. In 2003 KTM upgraded its 500-series with a 6-speed manual transmission. In 2012 the company did away with the carburetor and opted for the Keihin 42mm throttle body. This change bumped the bike's horsepower from 51 horsepower to 58 horsepower. The same year, KTM upgraded the motorcycle to a hydraulic multi-disc diaphragm spring clutch.
KTM's 500 EXC-F is a water-cooled bike. This means that, unlike more primitive dirtbikes, it has a water pump, radiator, and even radiator fan. Even on a hot day, navigating a slow trail, the KTM will not overheat. The KTM can also sit still in traffic without risking the engine melting down.
One major improvement to this generation of KTM dual-sports is the bike's reduced noise level. KTM 500 EXC-Fs ship with the relatively quiet Continental TKC80 tires. Many offroad enthusiasts swap them out for a more aggressive--and louder--set of tires. The latest EXC-F also has a surprisingly quiet muffler and now, a baffled air-intake. This system keeps the bike quiet (and legal) riding through even the strictest neighborhoods.
Racers Favor KTM Suspension
The current cadre of dual-sport motorcycles diverges on suspension setup. Some motorcycles feature high-tech suspension tuned for the street. These bikes suffer from softer suspension and a higher overall weight while offroading. Other dual-sport motorcycles still favor a stiff, race-ready setup capable of tackling the toughest trails.
KTM has a distinct advantage in the thesuspension-wars: the manufacturer offers two separate dual-sport brands. KTM's rise to motorcycle greatness is a fascinating story. In 1995 KTM acquired the Swedish company Husqvarna Motorcycles. Today, the company sells a heavier, more high-tech, upmarket dual-sport badged as a Husqvarna, as well as a more capable dual-sport badged as a KTM. Husqvarna's largest dual-sport is the FE 501S, resplendent with premium features, including linkage rear suspension.
The KTM 500 gracefully splits the difference between comfortable on-road and capable off-road suspension. When engineering the bike's front suspension, KTM replaced its motocross Xact air forks with WP Xplor coil-spring forks boasting 300 mm of travel. But in the rear, KTM stayed true to its race heritage with no-linkage Progressive Dampening System (PDS) suspension. Many other motorcycle companies have opted for linkage suspension, even on their motocross race bikes. But one of the reasons that KTM is an industry-leader is that extreme riders still prefer the PDS suspension.
The Reigning King Of The Dual-Sport
Unlike KTM's offroad-only motocross bikes, the 500 EXC-F sports a headlight, turn signals, and mirrors. The motorcycle also has a much larger gas tank than its offroad cousins: 2.2 gallons.
The KTM 500 EXC-F features offroad-ready bodywork, including handguards. KTM does not bother with traction control and launch mode, which weigh down some of its competitors. The resulting machine weighs in at only 244-lbs--fully-loaded with fuel. This makes the 500 EXC-F one of the lightest and nimblest motorcycles in its class. It is lighter than even its Husqvarna cousin. In overall weight, the KTM 500 EXC-F is beaten by its little dual-sport brothers: the versatile KTM 450 EXC-F and the venerable KTM 250 EXC-F.
KTM's latest dual-sport is not only legal on the street; it is comfortable. Past dual-sports were known for overheating, backfiring, and even stalling. The 500 EXC-F runs clean and quiet. It also behaves itself, running reliably and without fuss. Once upon a time, the more well-behaved dual-sports lacked power. But the 500 EXC-F produces excessive torque, even at mid and low RPM ranges. Dirt Rider website named the 500 EXC-F its undisputed winner of the 2019 dual-sport shootout. Despite new competitors, the motorcycle remains at the front of the pack for Dirt Rider's 2020 competition. The KTM 500 EXC-F is one of the best dual-sports of 2020.
Dual-sport motorcycles still have limits: The KTM's seat height is 38 inches. Its knobby tires are far from fuel-efficient and offer little traction to lean through a paved corner. But this next-generation dual-sport can deliver you from your home to the trailhead in comfort. Then it can tear up any trail with enough speed and power to make your dirtbike-riding friends jealous.
Sources: Dirt Bike Magazine, and Dirt Rider