Baja Brawler: The Desert Fighter KTM 500 EXC
In its stock form the KTM 500 EXC is a solid Enduro machine that's just as capable of cruising down the highway at 70-plus in sixth gear as it is jumping dusty creek beds or bee-bopping up and over rocky washes. Smooth shifting, smooth power, and smooth handling makes the 500 EXC a great bike for commuting, errand running, or just taking a weekend cruise to grab lunch. But where the bike really excels is when you let it loose in its more natural offroading environment.
Weighing in around 261 pounds, extremely agile, and with more than 13 inches of ground clearance, the 500 EXC can handle tricky single track switchbacks or flat out, wide open desert runs with ease. And while it's a great off road machine, as with most vehicles there's always room for improvement and components that can be swapped out or added to improve rideability or functionality.
In this instance we decided to mod a 2016 500 EXC to create a bike that would make a great pre-running machine for events like the Baja 1000. The main goals were to added some much needed protection, increase fuel capacity/mileage, and make a few key improvements to the drivetrain.
The stock EXC comes with blacked out Giant rims and Metzeler tires and even though the Metzelers are good tires the decision was made to swap them out with a set of tires that would provide better mileage and durability for harder pack and desert racing conditions. The perfect choice for the job was a set of Tractionator Desert H/T tires from Motoz. These tires are DOT approved so they can still be ridden on the street but are highly praised for their heavy-duty construction and ability to handle the treacherous conditions associated with hard pack desert racing. Most notably, Motoz claims these tires have been run in the Baja 1000 without needing a tire change. In addition to the Motoz tires the stock tubes were ditched and replaced with a set of Bridgestone Ultra Heavy Duty tubes.
To help improve braking the original 260mm front rotor was replaced with one of Galfer's 270mm Oversize Tsunami Wave Rotor Kits. The larger rotor provides better heat dissipation while the ceramic composite pads that come with the kit improve brake feel and performance. The floating design of the rotor also allows for better pad to rotor contact for increased stopping force. The nice thing about the kit is that even with the accompanying caliper bracket it's still relatively light.
Getting a flat out in the middle of nowhere can be a real pain, especially when you are traveling light and don't have a full range of tools at your disposal. Therefore to make tire repairs a faster affair, a pair of Enduro Engineering Axle Pulls were installed. The CNC-machined billet aluminum pulls will make it much easier to remove the axles when pulling the wheels off the bike.
The 500 EXC drivetrain delivers great power, however the stock 15/45 gearing leaves quite a bit to be desired. To better suit the terrain and conditions that this bike would be seeing the front sprocket was dropped down to a 14 tooth Renthal unit and the rear was increased by one tooth with a 46 Renthal sprocket. It's not a huge change in gearing, but this combination would help deliver a little more bottom end power and improved acceleration without sacrificing too much off the top end. Another key aspect of this sprocket setup is that it allows you to use the stock chain and not have to upgrade to a longer chain when in a bind. This will make unexpected repairs cheaper and make it easier to find a replacement OEM chain. Before the chain was installed a KTM/TM Designworks Chain Guide was installed along with a TM Designworks "Baja-Rally" Endurance 2 Stage Chain Slider.
The engine was left intact, however, to help make slow going technical sections a little easier to manage the clutch was replaced with Rekluse's Core EXP 3.0 clutch setup. The kit comes with a new center hub assembly, drive plates, pressure plate, clutch springs, the EXP disk, clutch cover, and slave cylinder housing. With its ability to automatically engage and disengage based on engine RPM speed the Rekluse clutch will allow the rider to stop the bike without having to pull in the clutch and not have the bike stall. The clutch will also make it easier to climb or navigate through difficult terrain in first gear without worrying about stalling.
The terrain in Baja can be brutal and really take a toll on vehicles, even when just pre-running, therefore in order to try and protect key components a host of guards and other accessories were added. The rear of the bike was treated to KTM's CNC-machined rear brake rotor guard and a carbon fiber rear caliper cover. To help shield the stock header from dings and dents and reduce heat on the rider's leg an Akrapovic carbon fiber exhaust guard was installed. High centering on a rock can cause catastrophic damage to the engine case, so the stock plastic skid place was replaced with a heavy-duty aluminum skid plate from Enduro Engineering and a Rekluse billet aluminum salve guard was mounted over the Rekluse salve cylinder on the left side of the engine. At the front of the bike the brake rotor was covered with an Acerbis carbon fiber cover secured in place with an aluminum axle mount. Up top a set of KTM Pro Bend Handguards were bolted up to offer a bit of protection for the rider's hands.
Running across unpredictable desert terrain at high speeds can get the front of your bike into some hairy situations like tank slappers, high-speed wobbles, and hard back and forth sweeps of the handlebars over rugged trails. To combat these situations a GPR V4 Stabilizer was installed. With its easy to use adjustable dial and fluid control the stabilizer helps dampen side-to-side jostling of the handlebar resulting in a more stable and steady ride while also helping reduce arm pump. As for the footing on the bike, instead of going with the standard hard-mount footpegs that only swivel up and back, a set of Pivot Pegz were installed. Made from high-strength, aerospace grade stainless steel, the pegs provide great grip and offer an extremely wide 60mm platform to help with control and reduce fatigue in the riders feet. The pegs are unique in the fact that they rotate forward and back with the rider's feet to provide full time traction, better comfort and control, and also help reduce impacts. A precisely-tuned self-centering spring allows the pegs to automatically return the neutral position.
A good headlight is an essential component to a safe and successful night time desert ride, so the stock headlight was tossed and in its place an ultra-bright Baja Designs XL Pro Squadron LED headlight was installed. Designed for racing and weighing in at under 2-1/2 pounds, this headlight delivers 4,900 lumens and 40 watts to cut through the darkness with a bright swath of light. With the optional dimmer box installed the rider can cut the light output by 50% when facing opposing riders or riding on surface streets and highways.
With a 2.3 gallon gas tank, making a Baja 1000 pre-run on a stock 500 EXC would be an endless series of gas stops. In order to reduce the amount of refuels an Acerbis 4.1 gallon gas tank was mounted on the backbone. Almost double in size, the Acerbis tank will significantly increase mileage and make running out of fuel in the middle of nowhere less likely. Once the gas tank was in place it was determined that the rear of the tank and the stock side covers didn't flow together very well and left large unsightly gaps. It took a few tries but we found that a set of side covers from a 2012 500 EXC model fit up much better an actually made the bike look like it came from the factory with the oversize tank and earlier model covers. Then to tie in the look of the tank with the rest of the bike, Magik Graphics was called upon to create a custom graphic kit from fender to fender. The graphics simply laid in place over tank, fenders, and fork legs and as you can see give the bike a factory look.
The last pieces that were added to the KTM was a set of grip doughnuts, Sicass Mirrors with Ram accessory mounts, a rear grab handle, and a Universal rear fender bags. With the Ram mounts you can quickly remove the mirrors or they can be laid down over the top of the handlebars so they are out of the way when not needed. And even though the bag looks small it's expandable and can be stuffed with a plethora of tools and other goodies to keep you motoring through the desert.
When all was said and done the KTM got a tire to tire makeover that would make it a more reliable and fun bike to ride across the Mexican landscape.
KTM 500 EXC BAJA BRAWLER SPECS SHEET
|Product Name||Part Number||Price|
|Galfer Oversize Wave Floating Tsunami Rotor Kit||014-KITOS33||$329.00|
|KTM 450/500 Enduro Engineering Skid Plate||056-24-080||$109.95|
|KTM Enduro Engineering Front Axle Pull||056-21-016||$19.95|
|KTM Enduro Engineering Rear Axle Pull||056-23-056||$19.95|
|Carbon Fiber Acerbis X-Brake Disc Cover||257-225025-0055||$189.95|
|KTM Natural Acerbis 4.1 Gal Fuel Tank||257-236775-0147||$275.95|
|KTM/Husky Aluminum Acerbis Disc Cover Mount||257-240311-0059||$29.95|
|Renthal 14T Front Sprocket||292-520-14||$25.95|
|KTM XL Squadron Baja Design L.E.D. Combo Light||305-50-0010||$374.95|
|KTM EXC Led Baja Designs Dimmer Box Kit||305-66-0088||$64.95|
|RAM Base with M10x1.25 Pitch/1" Ball||321-9079||$7.99|
|RAM Double Socket 2" Arm||321-9098||$12.56|
|Bridgestone 80/100-21 Ultra Heavy Tube||330-0981X||$58.95|
|Bridgestone 110/100-18 Ultra Heavy Tube||330-0985X||$48.96|
|TM Designworks Baja-Rally Endurance 2 Stage Chain SLDR||397-2017||$79.95|
|Rear Sprocket 46T||5841005104604||$79.99|
|Brake Caliper Guard Carbon||77713975120||$109.99|
|Pivot Pegz 60mm Footpeg Set||78003940244||$169.99|
|Rear Grab Handle||78112917000||$39.99|
|Universal Rear Bag||78112978000||$62.99|
|Brake Caliper Support||78113975144||$159.99|
|KTM EXC 2012 Air Filter Box Cover L/S||7720600300004B||$21.99|
|KTM EXC 20112 Air Filter Box Cover R/S||7720600410004B||$21.99|
|Motoz Tractionator 90/100-21 Desert H/T Dot Tire||909-090-100-21||$78.88|
|Motoz Tractionator 140/80-18 Desert H/T Dot Rear Tire||909-140-080-18||$107.88|
|Seat Concepts Carbon Fiber/Gripper Seat Cover with Orange Stitching||KT0171-11||$159.99|
|KTM Chapmoto Custom Graphic||GRAPHIC||$129.99|
|KTM 500 EXC Rekluse Exp Clutch||RMS-7782||$899.00|
|Sicass Racing Double Take Mirror||SAR-DT-M01||$25.00|
|SXS Carbon Exhaust Guard||SXS07250535||$89.99|
|GPR V4 Stabilizer Kit Cast||U6914814||$534.99|
|Smoto Grinder Handguards||U6951375||$119.99|
|KTM Grip Doughnuts Set||U6951716||$5.99|