Trail Test: KTM 250EXC

Testing and tuning on KTM's most popular enduro machine

The flywheel weight is held on with four socket head (4mm) counter-sunk screws that are majorly lock-tighted and a bear to get out. Rest assured though, it's worth the effort. Mind you the weightless flywheel didn't turn the bike into a motocrosser, as the advance curve is still the milder of the KTM ignitions. Nor has the bike proven easier to stall. In our humble opinion, this is the hands-down ticket for the '97 250 motivator, and the clincher is, it doesn't cut into your beer money in the process.

Suspension and Handling

In the handling department, the good news is the '97 250 retains its nice manners and continues to be plush over woods obstacles, a good turner and very stable steed. Even in the rough stuff with the suspension working and things flailing, if you keep your butt off the saddle, the bike stays on-line and provides an easy-handling platform. The new 50mm Marzocchi Magnum fork again employs independent left and right side damping duties, the left fork leg taking care of compression damping while the right side does rebound. The 50mm Magnum fork has 15mm less leg underhang than earlier Zokes, while maintaining 11.8 inches front suspension travel.

This is partially accomplished with a revised "gull wing" triple clamp design. An Ohlins rear shock is back for '97, updated with a larger reservoir; alleged to improve damping by giving the shock more oil to work with, and thus reducing fade. Rear suspension travel is 13.4 inches.

During our initial excursion shooting pictures, we were somewhat shocked when the 250 exhibited excessively soft suspension action at both ends, resulting in severe bottoming while jumping the bike during the photo shoot. Increases in compression damping at both ends was a temporary solution. Factory fork clicker settings finds 14 detents, adjustments accomplished using those sano blue knobs on the top of the fork leg. Factory set fork compression (left leg) damping was in the # 6 position (from full soft--CCW, minimum damping), and fork rebound (right leg) set at 10 clicks from full CCW.

Our knee jerk reaction bumped the fork compression leg to maximum compression, although we softened things somewhat since then, eventually migrating back to the #6 (surprise!) stock position. Rebound damping was softened somewhat as well, our final position (as of this writing) being five clicks out from full soft (full open/counter clockwise).

"Remember when spinning the Zoke damping adjustments, it's better to turn out the adjuster to full open (CCW) to begin any clicker adjustments."

Since the adjuster is a needle and seat assembly, any manhandling the clicker into the full closed (CW) position unnecessarily runs the risk of deforming the seat and ultimately confounding all damping adjustments. We found that with the fork compression and rebound damping cranked up, the bike worked pretty well when dealing with stadium-type obstacles--good in the whoops, big landings, but not-so-good over roots and logs, and a little stiff during the initial hit. With the current softer settings, the fork is plush, but still worthy of top level woods racing.

Air buildup, especially in the compression leg is still a problem, and when setting the fork up, be sure to rotate the fork leg so that the bleeder screw can be easily accessed. We witnessed riders bleeding the 50 mil Zokes on the trail, resulting in the fork settling (static sag) an additional 30-40mm! Likewise with the Ohlins shock we went gonzo after bottoming the back end during that first ride, and then eventually, succumbed to reason. The Ohlins unit provides 27 clicks of compression adjustment, set at 17 clicks from full hard (CW) from factory. Like with the fork, we increased compression damping (to the #14 position) and eventually worked our way back to the stock #17 detent.

The rebound adjuster likewise provides 24 choices for damping, factory standard set in the #18 position. Quite frankly, the suspension works great as set up as above, a fact proven under the duress of the recent ECEA opener Sandy Lane Enduro, and we’d be happy to keep racking up the mileage as is. However, we're about due for a fork oil change and it so happens that factory mechanic Tom Moen had some interesting recommendations in this area as well. Moen recommends less rebound to reduce packing on braking bumps, which seems to be better accomplished using thinner oil in the rebound leg, versus just reducing rebound damping. Stock ten weight fork oil is replaced with 7.5 weight in the rebound leg, and five weight in the compression leg. Maybe in an issue or two we'll have tried this and have the good word on it.

Aside from setting the fork oil level properly during assembly, our suspension and handling testing has been limited to the above clicker spinning and the installation of a WER steering damper. While not universally convinced of the merits of steering dampers for all situations, this WER unit is especially trick because it allows for a clean relocation of the ignition brain box, allowing the fork stops to be readjusted for tighter turning.

With respect to handling improvements, we were impressed by the additional stability offered by the steering damper-equipped KTM through deep, soft whoop-de-dos. Turning prowess was sharpened a bit by raising the fork in the triple clamp. Our initial setup started with fork cap/slider junction even with the top of the triple clamp. In this configuration, the front end pushed (on occasion), a situation perhaps confounded by the intermediate terrain Pirelli MT18 tires. This lead to some fantastic get-offs. To increase front end bias, the fork was raised in the triple clamp to the first notch in the slider resulting in better steering manners with no discernible effect on stability at speed.

The Trimmings

The '97 250 EXC comes fully equipped with all of the enduro trim we've come to expect. Headlight, tail light, license plate mounting, resettable odo, wide ratio 5-speed tranny, and a large fuel cell (13 liters) with a reserve position petcock. The only drawback is that the new EXC ignition lighting coil generates a mere 35 watts accessory power, versus the 130 watt lighting capacity provided by the old SEM ignition. Also, the Kokusan ignition mounts the brain box on the side of the steering head, in-between the triple clamps, reducing adjustable steering and confounding the installation of some steering dampers. Some riders remount the black box beneath the tank, while the WER steering damper solves both these problems with a trick mounting bracket that relocates the ignition box.

The '97 saddle comes with softer seat foam and a trick textured seat cover that provides excellent adhesion for the derriere. Plastic is adorned with a tasteful graphics update, black, gray and white stickers on a somewhat tamed orange-colored plastic (we thinks it's a lighter shade of orange). Finishing touches include Domino controls equipped with rubber boots to keep out dirt and water. Clutch action is excellent, with a nice smooth delivery that makes it easy to feed in the power. Sturdy aluminum shift and brake pedals and fine aluminum handlebars round out a top quality rider interface.

"The '97 KTM 250 EXC is a worthy mount for beginner or expert alike."

Unchanged from previous years, DID O-ring chain is standard on off-road models, driving steel front and aluminum rear sprockets. Stock 14/52 gearing keeps the motor in the meat of the powerband in nearly any situation, while dependable Brembo braking components provide good stopping power and feel at both ends. The '97 KTMs come shod with Pirelli MT18 tires which aren't bad all-around tires, but slanted more toward hard terrain, and they definitely give something away in loose sand and slick mud. The MT18 front meat pushes and eventually breaks away, while the rear tire spins without biting. We'll swap between our perennial favorite Dunlops in the sand and Trelleborgs in the rocks.

Regarding maintainability, a new radiator shroud mounting scheme eliminates problems associated with the old captured nuts. The new retaining nuts are crimped into the radiator mounting tabs and provide a very positive mount for shrouds. In an attempt to improve spark plug access, KTM installed a unique shorter spark plug. While this makes plug changes somewhat less of a hassle (not much), the plugs themselves are hard to find in non-KTM shops. After fouling the stocker, we installed a common NGK B8EV and have been running that plug ever since.

Our conclusion? The '97 KTM 250 EXC is a worthy mount for beginner or expert alike. Novice riders can leave on the flywheel weight for nice, controllable, but spirited power delivery. Hard chargers will ditch the flywheel weight in some conditions and perhaps bolt it back on for others. In all, it's a great bike and I hope that we get to hang onto it all season long. What are we going to do? Race the hell out of it and take names!

With a little luck we might even see an up-and-coming eastern enduro racer by the name of Mike Lafferty pilot a near-stock 250 EXC to the ‘97 AMA National Enduro Championship, but that's a story line yet to be played out. Either way, 1997 is shaping up to be a banner year for the folks up in Lorain, Ohio, and we're looking forward to being along for the ride.

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