TOM WEBB’S 500EXC: BEHIND THE BUILD

By Tom Webb

I really needed a dual-sport machine. Yes, we get test bikes, but by the time we get them dialed in to our needs, they get tugged back to the factory because new models are en route. As with anything KTM, the demand is high, and KTM’s sales staff is screaming for sellable units for their dealers. So, I bought one. This is a tough pill to swallow for an editor who has gotten loaners for decades, yet I knew my plans included some good rides in Colorado, Idaho, and Mammoth in Southern California, and having a well-setup, plate-legal machine would be mandatory.

I have been testing and playing with different mods on this machine for several months. For my extra-large frame and caboose, getting the suspension dialed in was priority number one. Number two on the list was ergonomics. I needed a taller saddle to keep the bend out of my knees, which don’t flex like they used to. I get the bars up and forward and search for increased legroom. Third on the list was gearing. Stock, it’s way too tall for any serious trail work and needs some additional snap to the powerband, which is nice but fluffy. Fourth on the list was traction; the stock rubber was barely acceptable on fire roads. And finally, there’s the doodad factor—items I wanted to enhance my experience with the KTM 500EXC. Here goes:

 

Kreft modified the WP XPLOR fork, an Acerbis grab-it handle was fit for tugging and Decal Works dialed in the graphics.
SXS Burly hand guards, PHDS bar mounts, a Trail tech Voyager GPS and a modded Seat Concepts ‘tall’ comfort saddle handle the cockpit.
A Motoz Gummy Extreme Hybrid tire with Tubliss, Dirt Tricks sprocket, RK XSO RX-Ring Gold chain, Bullet Proof Designs chain guide stiffener and a TM Designworks guide highlight the drive system on the 500.
FMF’s Q, a Slavens enduro rear fender and SAR taillights paint the rear of the machine.

 

Ryan Koch is about half of Wolf’s size, but loved the suspension and engine response mods he made to the EXC.

SUSPENSION
Kreft Moto, fore and aft
Getting your suspension done is an expensive pain in the derriere. You have to strip and ship your dampers off, hope that the suspension tuner is savvy and understands what you want to do in the dirt bike arena, and then wait two weeks to get it back. So, picking the right doctor is crucial. We have worked with Kreft Moto on several projects and have always come away stoked. Their methodology is based on suspension dynos, rider feedback and the physics involved with damping forces.

With my suspension setup, I need it sprung correctly, and I like to have some range of adjustability with the damping. Even with our 140-pound test rider, the 500EXC was soft. The XPLOR fork dove hard under braking, which affected cornering, and it was harsh on high-speed hits. At the same time the rear end tended to kick rollers and whoops, making the rear feel high. It was decent on regular trails, but got overwhelmed when the trails were hacked out and boney.

The Kreft valved shock helped reset the action making it far more planted fighting the dreaded PDS hop. The X-Trig pre-load adjuster is very trick and makes pre-load adjustments a very simple task.

Kreft yanked out the proverbial stops starting with the fork. The valving is customized to the rider’s size and skill level. It uses “firm but plush” valving that increases low-to-mid compression and decreases high-speed compression damping. They install their Revalve Control, a patent-pending externally adjustable mid-valve with the adjuster at the top of the left fork. This is the brain that allows the rider to re-valve the damping with the clicker, and it affects low-, mid- and high-speed compression. Kreft installed its Plush Port pistons, which replace the stock base valve, and fit in a new low-speed compression adjuster (the bottom of the left fork leg) that lets you fine-tune low-speed compression damping. Finally, the fork legs are micro-finished for smoother action.

Trail Tech radiator guards: Trail Tech radiator guards are super lightweight (forged and CNC-machined) and sano. They offer unobstructed front airflow and have an integrated spigot protector that protects the lower radiator spigot from sticks, rocks and crash damage. An Acerbis tug strap fit up quickly just in case the owner needed help.

Out back, the shock also received serious attention. First, it was sprung stiffer for my tonnage and then valved for my riding, which is high desert mated to woods trails and technical terrain. They fit in a dished piston, which is better for aggressive riding. They reduced the high-speed compression, which helped square-edged bump absorption, and the rebound damping curve targeted controlling top-out motion without packing. Kreft also fit its brand-new secondary compression piston, which targets the dreaded PDS kick on whoops and rollers. The new Centrifuge XL oversized shock reservoir helps to reduce fade by 35 percent, and Kreft installed its new Premium shock body, which is Kashima-coated and drastically reduces friction. The final mod was adding the X-Trig shock preload adjuster, which is a brilliant product. An 8mm T-handle turns a worm-drive system that offers the maximum adjustment range with minimal effort.

Webb has been using the STR rotor guard for several months and it has been up to the task. The unit is lightweight, and has a replaceable fin.
SXS Burly guards: We love the stock, perch-mounted handguards, but they do little to ward off blows from obstacles. Just bolting on the SXS Burly shields gives you superior protection, as the thick (yet lightweight) 1/4-inch plastic is the same stuff they build their skid plates out of. Nihilo lever guards give great finger grip.

TESTING THE BOINGERS
Okay, here’s the skinny. The Kreft suspension at the front end was flat stunning. The diving soft action was erased and replaced with balance, feel, control and improved cornering. Whereas hitting embedded rocks in third or fourth gear would about tear the bars out of your hands with the stock setup, with the new setup the impact was absorbed. You still felt it, but there was little deflection. Trail junk like roots and small embedded rocks were a menace. The firmer feel to the front has it riding higher, which helps the machine track and absorb, enhancing the control.

Out back, there were serious handling gains as well. The biggest win came in the whoops and rollers where you get that PDS kick. The rear feels like it rides lower (not wanting to top out), and this seemed to really help the balance of the machine. We noticed that it could absorb acceleration hack zones in the woods with less violence, which also helped with balance and control.

Here’s an interesting note: while we did adjust the Revalve Control when the trail got slow and nasty, we did not touch anything else, including the preload setting. It came set dead-on, which is our final word on the Kreft suspension. Like all suspension mods, it was expensive, but Kreft hit a home run with its XPLOR fork and XPLR shock modifications. 

Doubletake rear-view mirror: The Doubletake rear-view enduro mirror is a must for the serious dual-sport rider. It folds nicely out of the way for true enduro conditions and offers excellent visibility for the street. Wolf got his from Slavens Racing.
https://www.slavensracing.com
Trail Tech Voyager Pro GPS: We just started testing the Voyager Pro, as we’re prepping for a big dual-sport ride that is GPS marked. The hookup was straightforward, as the wiring setup was easy to follow. The actual mounting was a tougher proposition. We wanted it low and just above the bar perches, so we fabricated a mount for the unit. More to come once we get comfortable with all the features on the device. https://trailtech.net

GEARING AND BARK

 

52-tooth Dirt Tricks rear sprocket: The stock gearing is too tall at 14/48. We tried a 14/50, which helped considerably but created a too-tall second gear (second is crucial for trails and technical riding). Finally, we bolted on a Dirt Tricks (www.dirttricks.com) 52-tooth stainless steel sprocket and nailed it! The TM Designworks chain guide is almost mandatory for serious off-road.
Bullet Proof swingarm strengthener: A Bullet Proof swingarm guard keeps the chainguide from twisting and bending the swingarm tabs when it gets slammed by a boulder. Gotta have one! https://bulletproofdesigns.com
FMF Q: The stock muffler is very plugged and limits any available power increases. Just bolting on the Q, we felt a gain across the board, and the machine was much happier carrying taller gears through tighter woods sections. Also, it’s very quiet, which is key to a proper dual-sport machine.
https://www.fmfracing.com

TRACTION

Tubliss: T. Webb fit his steed with the Tubliss Dual Chamber tube, which allows for running really low air pressure without fear of pinch-flatting. He likes the ability to change air pressures—lower for technical trails and higher for highways. The Tubliss setup replaces conventional inner tubes with a small, red, 100-psi insert that creates two different pressure zones inside the tire itself. This gives 100 psi of rim protection, increasing tire stability and eliminating pinch flats. Plus, it will run totally devoid of air without the bead coming off the rim.
Vortex ECU: This makes the biggest power improvement but turns your dual-sport machine into a closed-course-only wagon; however, it’s plug-and-play and makes for serious performance gains throughout the powerband. When combined with the FMF Q, the transformation was incredible. Short-shifting without flaming out was the norm, and there was a tremendous amount of muscle from mid to top.
https://www.vortexcdi.com

ERGONOMICS

PHDS handlebar mounts: These are available from Slavens Racing, and I get less vibration, plus some cushion on impacts. The system also damps the forces acting on the handlebar in a horizontal and vertical direction, maintaining steering precision. They are super adjustable, and they are pricey but very well made.
https://www.slavensracing.com
IMS Low Boy Core pegs: For tall guys, lowering your pegs 5mm makes a huge difference in legroom. The IMS Core peg is a well-built brute, 5mm lower and 5mm back. Anyone with a long inseam will embrace them.
https://www.imsproducts.com
Seat Concepts tall comfort saddle: For the off-roader, it doesn’t get any better on your fanny than padding it with a Seat Concepts comfort saddle. It’s wider at the seat zone, is easy to move around on, has the best/comfy seat cover and has a tiered damping feel to the foam. I build mine up an additional 10mm.
https://www.seatconcepts.com

DOODADS

SAR blinkers/off-road taillight and fender: Although we never had any drama with the ponderous stock license plate holder, Webb wanted to streamline the back end of the machine. The blinkers were replaced with SAR units that mount to the rear fender and Enduro Engineering off-road taillights that come with a white fender and let us mount the plate up and out of harm’s way. Tom ordered the fender and SAR parts (blinkers and necessary parts) from Slavens Racing.
https://www.slavensracing.com
Slavens swingarm protector: This little device protects the swingarm from premature wear from the mud flap on PDS KTMs.
https://www.slavensracing.com
E Line heat shield: E Line makes a very sano carbon fiber exhaust shield that offers protection to both the header and your gear. The head pipe is susceptible to dings and dents as it gets hot, so it is critical to protect it from potential impact damage. The E Line shield also protects the O2 sensor on the header.
https://elineaccessories.com/
SXS Slide plate: The 500EXC does not have a skid plate and needs one! The SXS Slide plate is made from 1/4-inch UHMW plastic, which is lightweight and wickedly durable. You’ll get good coverage on both sides of the engine cases with this unit. It’s an easy bolt-on and a stellar protection device.
https://sxslideplate.com/

 

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