KTM 300XC 2-STROKE: FULL TEST

KTM can take a big chunk of the credit for the healthy state of the two-stroke world. KTM has never waned in its passion to pursue new technology and to back its commitment with a racing program that gives its equipment incredible credibility. The new 2021 300XC TPI is a direct result of pursuing perfection in a machine that has an appetite for a broad range of off-road meals.

The 300XC uses linkage, the WP fork is the Xact Air, the tires are Dunlop and the strong braking systems are Brembo. It is lean, electric start only, is oil-injected, and runs clean and hard. The side stand is excellent and the exhaust note is acceptable, though it lacks a spark arrestor.

 

KTM introduced Transfer Port Injection in 2018 on the 250XC-W machines. TPI technology provided clean power that was smooth, tractable and usable. There were a few bugs to work out, as the machines had spotty ECU mapping that ran both lean and rich, but by 2019 many of these “unique” traits had been dealt with. KTM limited the TPI and oil injection to the XC-W (enduro) line, going with carbureted engines on the XC bikes until KTM introduced the cross-country line to TPI in 2020.

The 2021 KTM 300XC TPI is a cleaved-to-the-bone, off-road weapon equipped with every technological performance gain KTM has in its little black book. Here’s a look at the skeleton of the machine.

THE BONES
The cylinder on the 300XC is power-valved and uses EFI (two domes house injectors that supply fuel into the transfer ports). The result is good atomization of the fuel, fewer emissions via more efficient fuel combustion and better fuel economy. It has a balancer shaft that reduces vibration at the engine; a 6-speed, semi-close transmission (different from the wider-ratio XC-W); and KTM’s DDS clutch that uses a diaphragm spring mated to Brembo hydraulic actuation, making for a very light pull and superb feel at the clutch.

It is oil-injected (no gas/oil mixing) via an oil-intake tube from the oil pump that mixes with incoming air to lubricate key areas inside the engine. The engine management system has the control unit under the seat.  It controls ignition timing and proper fuel input based on readings of air pressure, throttle position, water pressure and ambient air temperature. The result is no jetting required, courtesy of the altitude and temperature compensation abilities of the system. The entire engine is very compact. The bike is electric start only and comes fit with an exhaust system that features a beefed-up belly to ward off blows.

At the chassis, KTM has been known for its chromoly steel frames, touting their ability to offer better feel. The bike has new cylinder head stays for better cornering and less vibration, and uses an aluminum/removable subframe. The wheels have machined hubs, Giant rims and Dunlop AT81 rubber.

With KTM as the parent company, WP suspension is used on the machine. The fork is the WP XACT unit that uses AER technology. Boiled down, that means it’s an air fork. It has separate functions in each leg, with the left being the spring (air pressure) and the right side handling the damping. Each machine comes with an air pump, and it’s a single valve for adjustment ease. For 2021 new damping strategies have been configured, and there is a new piston for a plusher ride.

Out back, the shock runs through the linkage and has new settings this year to improve traction, comfort and versatility. The WP XACT shock is a machined unit and features high- and low-speed compression and rebound damping adjusters.

At the triple clamps, the XC line uses CNC-machined clamps for a precise feel. The Neken bars are rubber-mounted, have two-position adjustability and are fit with ODI grips. The brakes are Brembo and use wave rotors. The gas tank totes 2.4 gallons and has an internal fuel pump and fuel-level sensor.

LET’S BEAT IT UP!
One of the best traits of the new TPI bikes is the smooth character of the power. You can be much smoother with the throttle and make better traction in nasty conditions than on a carbureted bike. The power is ultra linear and isn’t twitchy, making it easy to lug the bike through miserable terrain. The throttle response is instant and always ready for any obstacle. There is never any hesitation or a bog to worry about, as there is with an improperly jetted two-stroke. A big plus is how well it runs at elevation.

The counterbalanced TPI engine is the smoothest engine in its class. While others state they come with a counterbalancer, the KTM is the only one that actually feels like it has one. The bike vibrates so little, it’s a game-changer. This year the spread of power has improved; it is stronger down low and very potent into the midrange. It was almost too much, so we adjusted the power-valve spring out two turns. This helped spread out the hit. It does not have that big two-stroke smack that the carbureted 300 exhibited, but it is strong, broad, smooth and potent throughout the pull. It ties in perfectly with the 6-speed, semi-close-ratio gearbox. We loved the spacing of the gears, with first gear being plenty low for technical trails. There are no gaps anywhere in the transmission, and that makes it nice for tight trails or on the track. Compared to the XC-W machine, first through fourth lacked any gap at all, with fifth and sixth being taller. The XC-W has larger gaps between second and third with a taller overdrive. For hydraulics, the bike comes standard with Brembo units all around. The clutch performance is amazing, with a super-smooth pull and zero fade, even when abused.

The brakes offer a smooth and consistent feel, making it very easy to modulate them into corners or on downhills. The bars are Neken with awesome ODI lock-on grips. We also are pleased the bike comes standard with handguards. While they aren’t much, they do help in the brush.

We talked about the separate functions on the XACT AER fork, and we ran the standard 9.6 bar in the right fork for our off-road riding. We were pleased with the feel both at slow speeds and on high-speed impacts. We rarely fiddled with the pressure, and the suspension accepted input from rocky zones and technical trails with a plush-enough result. The AER fork does not have the XPLOR fork’s cushiness, but then again, it’s far better on high-speed hits, whoops and G-outs.

The XACT rear shock plays nice with the fork. The balance of the bike is impressive, and the shock is just as plush as the forks yet offers great bottoming resistance. The plushness of the shock allows you to load the shock in technical situations to make traction and put the power to the ground. It remains firm enough to stay up in the stroke over whoops or in faster terrain without being too soft.

The chassis feels incredibly stable no matter what the conditions while offering the proper amount of flex for comfort. This bike turns exceptionally well; it is precise on twisty trails or tracks with tight corners. The bike feels narrow with its 2.4-gallon fuel tank, and kudos to KTM for the saddle, which is more comfortable than in years past.

NOTES, OBJECTIONS & OBSERVATIONS
We had zero issues with the oil injection, and this certainly helps with the clean and tight powerband. The KTM 300XC comes with an hour meter but no trip meter of any kind, which is fine, since it’s technically a race bike. The oil light and fuel light are located on the triple clamps by the hour meter to indicate when those liquids get to their lower limits. We were able to go through over six tanks of fuel before the oil level in the tank even dropped enough to be seen, but we would top it back off just so we would not fear running out while in the mountains.

We’d like to see the map switch that the Husqvarna models come with, but that can always be added to get a bit more versatile performance out of your machine. Because this is a closed-course race machine, it lacks a spark arrestor; however, we still need them where we ride!

It has no kickstarter, but that doesn’t concern us. We still have our 2019 300 with a kickstarter that has never been used!

We’re disappointed the bike has no stock skid plate. It only takes one misplaced rock to end your day and damage the machine you just financed. Also, the linkage hangs extremely low on this bike, so make sure you get a skid plate with a linkage guard as well. We equipped ours with an SxS unit.

Once again, we love the easy-access air filter and large airbox that allows you to see the entire filter sealing surface to make sure it’s seated properly.

GIVE ME A SHOT OF THAT JUICE!
Overall, the 2021 KTM 300XC can be ridden anywhere and do anything you ask it to. You can ride extremetechnical terrain one day, desert the next and follow up with a day at the track. It’s an incredible off-road weapon that works perfectly for the vet trail rider or elite hard enduro athlete. It’s fun. It purrs, but it snarls just enough and won’t set your teeth chattering from the vibration factor. It honestly doesn’t get a whole lot better than this!