LIVING WITH THE KTM 300XC-W TPI 2-STROKE
Living with the KTM 300XC-W TPI machine is no great burden. This machine satisfies the off-roader’s needs like Aspartame fuels a Diet Coke fanatic. Incredible bottom-to-mid power is highlighted by a vibration-free response, allowing even the pedestrian pilot to conquer trail obstacles while feeling like Jonny Walker. It’s clean. It has a button. The power is seamless, and it craves ugly stuff. Over the last four months we have ridden this machine at least twice a week and have learned volumes about maintenance, upkeep, minor flaws and how to charge the machine with more vigor.
We have been working with Jeff from Slavens Racing to find some additional meat for the powerband and to learn basic tips for living with a fuel-injected, oil-injected and highly evolved machine. Jeff’s history goes way back. First, he’s a huge off-road riding advocate from Colorado, and second, he loves two-strokes. He built Rodney Smith’s race engines for years, was a suspension specialist and runs his company with a straightforward plan—make the bikes better, test the products that work, and give riders this information so they can get the right goods and learn how to do it themselves.
So, what we have come up with is a project where we deal with some of the weak points. We have made suspension updates, ECU mods, ergonomic changes, added performance bolt-ons and then dealt with maintenance on the injected machine. Slaven Racing graced us with its pre-ride checks, what to keep an eye on and performance mods they have tested and endorsed.
THE FIRST STAGE
Several months ago we dove into the biggest dilemma we faced, getting the soft suspension to work for a larger or more aggressive rider. In stock trim, there is no doubt that it’s plush. In fact, we have four friends who have bought the 300 TPI machine and really have no issues with the suspension. They like how it reacts and absorbs the rocks, roots, ruts and detritus that come with tight enduro riding. But, most of them weigh under 175 pounds and are so enamored with the sweet, smooth power they bounce right over the suspension drawbacks. The bottom line is that plush and soft suspension is far better than stiff and harsh damping for the off-roader.
We had Kreft Suspension re-work our dampers, and nearly four months later we’re still overjoyed with the modifications. The Xplor fork required some dramatic changes to the compression paths and spring rates to get it to stay up in the stroke yet retain a strong ‘plush’ factor. Out back, they went stiffer on the spring rate, stuck with a progressive coil and re-valved it to track, and respond to a larger variety of off-road inputs. For our 200-plus-pound rider, it wasn’t even close. Back to back with stock, the Kreft machine is just as cushy but can handle speed hits, whoops and G-outs with an appetite that the stock fork lacks.
We strongly sanction E-Line’s carbon fiber pipe guard, which still protects the vulnerable stock chamber. TM Designs’ chainguide has been hacked on and abused, still with no drama to the drive chain, and Bulletproof’s guide strengthener keeps the chainguide from bending and derailing the chain in a direct hit. Enduro Engineering’s rear disc guard has been attacked and has survived trail hammering, and its front aluminum lower fork-leg guards have been abused yet are still strong.
STAGE TWO
Our focus with Stage 2 would be power—not really the amount of usable thrust, but addressing the leanness when loaded hard and revving it under duress. In trail conditions, short-shifting is key, and the engine offers superb, tractor-like response. No drama. Hill-climbing with the throttle slammed in second or third gear for long periods showcases that the ECU comes mapped lean. It’s very similar to a carbureted machine jetted too lean. It lacks meat and won’t pull with authority. Because this is a closed-course machine, switching out the ECU with an aftermarket unit is totally legal.
Slavens Racing is a big Get ECU supporter. In Jeff’s words, “The stock maps are too rich at very low rpm, and that causes them to load up upon initial startup. The overly rich condition makes the power delivery soft down low then above too lean, which gives tinny, weak power that pulls in to a decent top end. The Get ECU (with custom Slavens maps) corrects the rich and lean issues and creates a much stronger and more linear power from bottom to top.”
Our first mod was installing the stock Get ECU with its two maps. One was for straight power. Map two was with traction control. Installation was simple (though the instructions were weak); we routed the map switch and then set the ECU in its compartment above the airbox. We felt a strong improvement in roll-on but an equally impressive boost in the midrange. It was meatier, resulting in more usable power. We liked it, but at $984, it was a mod for a Beverly Hills dentist. Slavens remapped it with his numbers. Jeff customized a setting that took away some of the rich initial feel and then richened up the mid and top settings. His map two was a dumbed-down traction-control setting for slippery, rocky, ugly conditions. Big difference here! Stronger roll-on, a nice strong mid portion, and a robust rev-it-out mode made the machine come alive. The machine gets additional torque and a power gain throughout—all making the machine easier to ride.
Jeff is also a big believer in adding compression, calling it the cheapest way to add low-end grunt. The Slavens Mule component head kit is manufactured by S3 for Slavens and uses compression ratios to maximize performance for low and high elevations. The kit consists of the head shell and two inserts—a Low-Elevation Mule insert for riding at 0 to 6000 feet of elevation and a Mountain Mule insert for high elevation (6,000-12,000 feet). Its forged aluminum offers increased coolant capacity and does not require race gas. We went with the hi-compression insert for our elevation, and you must have the GET ECU with the Slavens maps, since it’s too lean stock and you’ll run the risk of cooking your motor. The result? Wow! The machine got considerably stronger. It is a touch snappier but a total tractor in low- and mid-power riding zones. Ultimately, the S3 Mule hi-compression head and the GET ECU were like an IV of steroids. They made it stronger everywhere but just as rideable. Of note, the kit does not come with new O-rings but is very easy to install.
terrain. They are DOT legal!
While we protected our stock expansion chamber with an E-Line Carbon fiber guard, the stock KTM, which is excellent power-wise, is easily crushed or dented severely. They’re consumable, so unfortunately you’re going to have to have a replacement system. FMF Racing builds its Gnarly pipe out of thicker material and is designed to enhance the bottom power. We’ve been beating up the Gnarly system for a month. It may have a few whacks, but it does hold up incredibly well. It moved the power around and when mated to an FMF Power Core II muffler (designed for the TPI machines) a fairly strong hit in the mid-range replaced the linear band of power. Stronger more aggro riders liked it, the trail riders like it smoother.
THIS AND THAT
Wheels: The stock rims are lightweight but prone to easy damage. Take care during break-in to keep the spokes taut. We wanted an additional set of wheels and went with Moose Racing’s Wheel Kits. You must assemble them, but they’re priced separately, with the rim at ($119.95), MXI hub ($185.95-219.95), spoke kit ($43.95) and spoke nipples ($35.95), which look great and hold up nicely. We added EBC’s larger front rotor kit and its rear disc and carbon pads. The larger rotor enhances the stopping power. We’ve gone through the stock chain and sprockets (both of which were durable) and replaced them with Sunstar sprockets with the EXCR1 O-ring chain. We have used Sunstar kits in the past and like the rear sprocket’s durability and the chain’s strength and lack of stretching over time. Quality stuff.
Tires: We have tested a glug of rubber. For our neck of the woods, good marks go to the Golden Tyre Fatty front and the 323 rear, Metzeler’s MC360 Mid, Shinko’s Cheater and the MotoZ Hybrid. We’ve been sticking with the MotoZs mainly because they make great traction and hold up as well as any rubber we have tested. Inside them, we’re big on Mousses now (hate flats) and have been running the new soft Nitro-Mousse foam inserts. They give better feel for tight off-road (feels like less air pressure). We don’t leave home without them.
Cockpit: We’re still running the stock bars, but they’re attached to PHDS handlebar clamps. These babies are excellent and take some of the jolt out of the trail. Grip wise, the new ODI Emig bolt-ons are right at the top of the list. We love the additional padding on the top of the grip! We have one of our editors who needs a tall saddle and is using a tall MX Control Tech seat with excellent results. It has ribbed channels where your legs pinch the saddle, and it helps keep you in the right stance in rough terrain. We have tested a Seat Concepts kit, which is cushier and offers good feel and fanny traction. Honestly, the stock seat cover and foam are hard and slippery. The IMS Core pegs are incredibly beefy, and they offer a lower version, which our tall guys prefer.
Handling: We added a Scotts Performance steering damper after we rode Dicks Racing’s modded bike a few months ago. The damper lets you run the fork softer and takes out the willies when things start getting fast and rough. The adjustability is superb. The ability to stay on the straight and narrow when the horse starts to shake its head is much appreciated.
AND SO…
Frankly, we love the KTM 300XC-W TPI stock. The suspension mods were a big improvement. The Slavens Get ECU was a huge improvement. The S3 Mule head and FMF exhaust combo is stellar. Add in our well-tested product mods, and life with the 300 is bright. Here’s a big thanks to everyone who played a role in our “Living with the KTM 300XC-W TPI”!
WEBSITESwww.fmfracing.com
http://pacificpowersports.com/products/motoz-tires/
http://nitromousse.com/www.trailtech.net
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