2017 · Enduro · Buyer's Guide
Two-Stroke Enduro Taken Seriously
The 300 EXC is built around a counterbalanced 293 cc two-stroke making 54 hp and 30 lb-ft, and the torque figure is the one that matters out here. The power arrives in a long, usable spread rather than one hit, so the bike will chug a rock step at walking pace or pull across open desert without a gear change. WP XPlor suspension is adjustable at both ends, the clutch and brakes are Brembo hydraulics, and there is an electric start button. Six speeds, 21-inch front, 18-inch rear. Nothing on it exists to look good in a brochure.
On the trail the character is pure orange: light, direct, always asking for a little more commitment than you planned to give. With 14.6 in of ground clearance and close to a foot of travel at each end, it goes where lines stop looking like lines. This is not a gentle first dirt bike. It rewards fastidious maintenance and punishes neglect. The honest caveat is hours. Bottom-end bearing failures turn up in the 220 to 280 hour window, so a rebuild belongs in your ownership math from day one. Budget for that and you have a genuinely serious tool.
Spec sheets don't ride bikes, but they set the baseline.
| Power | 54 hp (40 kW) |
|---|---|
| Torque | 30 lb-ft (40 Nm) |
| Displacement | 293 cc |
| Engine | Single-cylinder |
| Cooling | Liquid-cooled |
| Gearbox | 6-speed |
| Final drive | Chain |
| Fork | Upside-down (USD) |
| Front tire | 90/90-21 |
| Rear tire | 140/80-18 |
| Ground clearance | 14.6 in (370 mm) |
| Front travel | 11.8 in (300 mm) |
| Rear travel | 12.2 in (310 mm) |
| Seat height | 37.8 in (960 mm) |
| Fuel capacity | 2.5 gal (9.5 L) |
Equipment check
Chassis
Everything below comes from riders, not from me. Two decades of paddock talk, workshop conversations, club nights, and the messages that land in my inbox from people who actually own these bikes. On the 300 EXC the pattern is consistent: praise for how the bike behaves underneath you, and a running conversation about the fueling.
The engine comes up first, almost every time. Owners describe it lugging cleanly up steep, technical ground without stalling, then revving out when the trail opens. Close behind is the electric start, which riders call a genuine relief in awkward spots. The WP XPlor suspension gets steady praise for soaking up rocks and roots without bottoming, and for how easily it adjusts. Riders also keep returning to how light it feels on tight singletrack, and how much less worn out they are at the end of a day. The Brembo brakes draw regular mention for their modulation.
Jetting dominates the complaints. Many owners report inconsistent fueling from the Mikuni out of the box and a fair number switch carbs to sort it. Less often, riders mention the power valve sticking over time and turning the low-to-mid power erratic until it gets cleaned. A few report fork seals weeping early in muddy conditions, and some faster riders find the plush fork action short on control when they push.
Mikuni carburettor jetting and bog issues
The stock Mikuni TMX can bog or run lean/rich; many riders swap in a Keihin PWK for more consistent fueling.
Bottom-end failure at high hours
Several owners report catastrophic bottom-end bearing failures between 220–280 hours of riding, requiring a full rebuild.
Power valve sticking
Carbon deposits can cause the exhaust power valve to hang, reducing low-end power or causing abrupt hits.
Fork seal leaks
WP XPlor fork seals may weep oil, especially after rides in abrasive mud, requiring replacement.
Starter motor/in-tank electrical gremlins
Poor grounding at the subframe or stator wiring faults can cause intermittent starting issues.
Overheating in slow, technical terrain
The engine can run hot and even boil over in slow, tight riding conditions, possibly due to lean jetting or insufficient cooling.
Where this KTM 300 EXC pulls ahead of — or falls behind — its rivals on the numbers, and the typical bike in its class on character.
Power
Torque
Displacement
Seat height
Forget spec-sheet bragging. Here's who the 300 EXC is actually built for.
This is your bike. Slickrock ledges, sand and tight technical lines are exactly what the clearance, traction and low weight are for. Plan the day around fuel stops, because the tank is small.
Made for Bar M / Kane Creek · Imperial Sand Dunes · Johnson Valley OHV Area
It will happily do track days, but it is geared and tuned for traction rather than starting-gate drag races. Fine for training and fun; a dedicated motocrosser beats it on a groomed circuit.
Made for Carnegie State Vehicular Recreation Area · Fox Raceway at Pala · Glen Helen Raceway
Wrong tool for multi-day route logistics. The 2.5 gal tank and tall, hard seat make the connecting miles real work, even though it will eat the hardest sections of any route you plan.
Made for AZBDR — Arizona Backcountry Discovery Route · California BDR South · COBDR — Colorado Backcountry Discovery Route
If you're cross-shopping the older generation, here's what changed.
Previous generation · 2011–2016
Two-Stroke Power, Zero Mercy
Compare to the previous model →If this one isn't quite the fit, these are the bikes worth riding back-to-back against it.
