SX, SX-F, XC, XC-F, XC-W, XCF-W, EXC-F: What does it all mean? I get this question a LOT, so I wanted to put this out there to explain the differences so that you can make the right decision when you purchase your next motorcycle. I want this to be a quick reference not a complete exposition, so we'll jump right in.
*See chart at bottom of article for the quickest of references.
SX/SX-F: I don't know if this is what the manufacturer has in mind, but I like to think that the letters mean something. In the case of the SX, I like to think of Supercross, often abbreviated with the same letters, SX. Adding the "-F" denotes that it is a four-stroke engine. The SX models are intended for use on Motocross or Supercross tracks. These are the same bikes that you saw Ryan Dungey on when he won 3 Supercross titles in a row, and the same bike that Cooper Webb is on now. With other manufacturers, the bikes the pros are riding and the bikes sold to the public are vastly different. KTM's Factory Editions shrink that gap, and you'd be very surprised how close they really are.
SX/SX-F models have 19" rear wheels, closed-chamber WP AER XAct front forks, linkage suspension, and the highest output engines available from KTM. They are the lightest and the highest HP available. I recommend this bike to riders who are strictly going to the motocross track.
Two-stroke SX models come in a 125cc, 150cc, and 250cc.
Four-stroke SX-F models come in a 250cc, 350cc, and a 450cc with a whopping 62 HP at less than 220lbs.
XC/XC-F: When you see these letters, think "cross-country." This bike is designed for Hare Scrambles, faster open trails, and more aggressive woods riding. They are built on the same engine and frame as the SX models (with the exception of TPI bikes) but with some changes. The XC models are tuned a little differently than SX models to smooth out power delivery and make it less explosive. This helps with traction and control in the trail without losing much peak HP.
These bikes have an 18" rear wheel, keep the same suspension, get a higher-output stator, add a 6th gear, get more fuel capacity, and add hand guards. I recommend this to riders who may have ridden motocross but are getting out in the woods. It is great for those doing SORCS racing, and anyone who likes to hit obstacles head-on rather than going around them. It can do both woods and track, but it is most happy in the woods.
On closed-cartridge suspension and linkage: This suspension setup is great for attacking sharp-edge fast impacts. It is not the best for single-line trails unless you're REALLY fast. For more detail on how closed cartridge suspension handles, come in to talk to Jeff.
The XC two-strokes are available in 250cc, and 300cc.
The XC-F four-strokes are available in 250cc, 350cc, and 450cc.
XC-W/XCF-W: When you see the W you can think one of two things, "woods" or "wide-ratio." Theses bikes are built to spend all of their time in the woods and can handle the gnarliest sections of single track you can find. They are great for hill climbs, rocky surfaces, and extreme enduro. You see pros like Johnny Walker winning international enduros on the XC-W, and locals have seen Cody Webb win the Tennessee Knockout Extreme Enduro on this bike.
These bikes share the same 18" rear wheel as the XC models, but drop the linkage for the PDS, and go to the open chamber WP XPLOR front forks. They also get a headlight and taillight, a wide ratio transmission with 6 gears, and a smoother engine to help you maintain traction.
On Open-Chamber Forks and PDS: This set up is great for single line. The open chamber front forks are plush and soak up everything you hit. PDS stands for progressive damping shock. The PDS gives the plush feel of a linkage without having something hanging down to get caught on rocks and logs as you cross over. Riders love the rear wheel feel and feedback it gives you that you lose when you go to linkage.
The XC-W two strokes are available in 250cc and 300cc.
The XCF-W four strokes are available in 350cc and 500cc.
EXC-F: When you think EXC-F, think... Alright I don't have a method to help your memory on this one, but I've done pretty well so far. These are your street-legal four strokes. People tend to lump these in with the Japanese 650s as slow and heavy, but that's not the case at all. For all intents and purposes, this bike is an XCF-W that is smog controlled to meet EPA and DOT standards. That does affect HP and weight, but not to a large degree. I have been unable to find a reliable number for HP, but the 500 EXC-F weighs only 240.3lbs wet without fuel. That means you have a light, offroad-capable dual sport that is lighter than most Japanese offroad-only bikes (and more power too).
The EXC-F is only available as a four stroke 350cc or500cc.
Like I said, this is not exhaustive, and I still learn something new every day. Hopefully this helps make sense of the different models that KTM has for those who are new to the brand or were still confused. I also hope that this helps you make the RIGHT choice of motorcycle without much trial and error. Use this handy chart I made and attached below if you want a quick reference.
Thank you for reading,
Jeff Griffith
